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Li X, Chang P, Liu X, Kang Y, Zhao Z, Duan Y, Liu J, Zhang W. Exhaled breath is found to be better than blood samples for determining propofol concentrations in the brain tissues of rats. J Breath Res 2024; 18:026004. [PMID: 38211315 DOI: 10.1088/1752-7163/ad1d65] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/20/2023] [Accepted: 01/11/2024] [Indexed: 01/13/2024]
Abstract
The correlation between propofol concentration in exhaled breath (CE) and plasma (CP) has been well-established, but its applicability for estimating the concentration in brain tissues (CB) remains unknown. Given the impracticality of directly sampling human brain tissues, rats are commonly used as a pharmacokinetic model due to their similar drug-metabolizing processes to humans. In this study, we measuredCE,CP, andCBin mechanically ventilated rats injected with propofol. Exhaled breath samples from the rats were collected every 20 s and analyzed using our team's developed vacuum ultraviolet time-of-flight mass spectrometry. Additionally, femoral artery blood samples and brain tissue samples at different time points were collected and measured using high-performance liquid chromatography mass spectrometry. The results demonstrated that propofol concentration in exhaled breath exhibited stronger correlations with that in brain tissues compared to plasma levels, suggesting its potential suitability for reflecting anesthetic action sites' concentrations and anesthesia titration. Our study provides valuable animal data supporting future clinical applications.
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Affiliation(s)
- Xiaoxiao Li
- Department of Anesthesiology, West China Hospital, Sichuan University, Chengdu, People's Republic of China
- Laboratory of Anesthesia and Critical Care Medicine, National-Local Joint Engineering Research Centre of Translational Medicine of Anesthesiology, West China Hospital, Sichuan University, Chengdu, People's Republic of China
| | - Pan Chang
- Department of Anesthesiology, West China Hospital, Sichuan University, Chengdu, People's Republic of China
- Laboratory of Anesthesia and Critical Care Medicine, National-Local Joint Engineering Research Centre of Translational Medicine of Anesthesiology, West China Hospital, Sichuan University, Chengdu, People's Republic of China
| | - Xing Liu
- Department of Anesthesiology, West China Hospital, Sichuan University, Chengdu, People's Republic of China
- Laboratory of Anesthesia and Critical Care Medicine, National-Local Joint Engineering Research Centre of Translational Medicine of Anesthesiology, West China Hospital, Sichuan University, Chengdu, People's Republic of China
| | - Yi Kang
- Department of Anesthesiology, West China Hospital, Sichuan University, Chengdu, People's Republic of China
- Laboratory of Anesthesia and Critical Care Medicine, National-Local Joint Engineering Research Centre of Translational Medicine of Anesthesiology, West China Hospital, Sichuan University, Chengdu, People's Republic of China
| | - Zhongjun Zhao
- School of Mechanical Engineering, Sichuan University, Chengdu, People's Republic of China
| | - Yixiang Duan
- School of Mechanical Engineering, Sichuan University, Chengdu, People's Republic of China
| | - Jin Liu
- Department of Anesthesiology, West China Hospital, Sichuan University, Chengdu, People's Republic of China
- Laboratory of Anesthesia and Critical Care Medicine, National-Local Joint Engineering Research Centre of Translational Medicine of Anesthesiology, West China Hospital, Sichuan University, Chengdu, People's Republic of China
| | - Wensheng Zhang
- Department of Anesthesiology, West China Hospital, Sichuan University, Chengdu, People's Republic of China
- Laboratory of Anesthesia and Critical Care Medicine, National-Local Joint Engineering Research Centre of Translational Medicine of Anesthesiology, West China Hospital, Sichuan University, Chengdu, People's Republic of China
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Schanzmann H, Ruzsanyi V, Ahmad-Nejad P, Telgheder U, Sielemann S. A novel coupling technique based on thermal desorption gas chromatography with mass spectrometry and ion mobility spectrometry for breath analysis. J Breath Res 2023; 18:016009. [PMID: 38100823 DOI: 10.1088/1752-7163/ad1615] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/07/2023] [Accepted: 12/15/2023] [Indexed: 12/17/2023]
Abstract
Exhaled breath analysis is evolving into an increasingly important non-invasive diagnostic tool. Volatile organic compounds (VOCs) in breath contain information about health status and are promising biomarkers for several diseases, including respiratory infections caused by bacteria. To monitor the composition of VOCs in breath or the emission of VOCs from bacteria, sensitive analytical techniques are required. Next to mass spectrometry, ion mobility spectrometry (IMS) is considered a promising analytical tool for detecting gaseous analytes in the parts per billion by volume to parts per trillion by volume range. This work presents a new, dual coupling of thermal desorption gas chromatography to a quadrupole mass spectrometer (MS) and an IMS by operating a simple splitter. Nearly identical retention times can be reached in the range of up to 30 min with slight deviations of 0.06 min-0.24 min. This enables the identification of unknown compounds in the IMS chromatogram using unambiguous mass spectral identification, as there are still no commercially available databases for IMS. It is also possible to discriminate one of the detectors using the splitter to improve detection limits. Using a test liquid mixture of seven ketones, namely 2-butanone, 2-pentanone, 2-hexanone, 2-heptanone, 2-octanone, 2-nonanone, and 2-decanone with a concentration of 0.01 g l-1reproducibilities ranging from 3.0% to 7.6% for MS and 2.2%-5.3%, for IMS were obtained, respectively. In order to test the system optimized here for the field of breath analysis, characteristic VOCs such as ethanol, isoprene, acetone, 2-propanol, and 1-propanol were successfully identified in exhaled air using the dual detector system due to the match of the corresponding IMS, and MS spectra. The presented results may be considered to be a starting point for the greater use of IMS in combination with MS within the medical field.
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Affiliation(s)
- Hannah Schanzmann
- Laboratory of Applied Instrumental Analytical Chemistry, Hamm-Lippstadt University of Applied Sciences, Hamm, Germany
- Faculty of Chemistry, Instrumental Analytical Chemistry, University of Duisburg-Essen, Essen, Germany
- Institute for Medical Laboratory Diagnostics, Center for Clinical and Translational Research, Helios University Hospital Wuppertal, Witten/Herdecke University, Wuppertal, Germany
| | - Veronika Ruzsanyi
- Institute for Breath Research, Leopold-Franzens-Universität Innsbruck, Innsbruck, Austria
| | - Parviz Ahmad-Nejad
- Institute for Medical Laboratory Diagnostics, Center for Clinical and Translational Research, Helios University Hospital Wuppertal, Witten/Herdecke University, Wuppertal, Germany
| | - Ursula Telgheder
- Faculty of Chemistry, Instrumental Analytical Chemistry, University of Duisburg-Essen, Essen, Germany
| | - Stefanie Sielemann
- Laboratory of Applied Instrumental Analytical Chemistry, Hamm-Lippstadt University of Applied Sciences, Hamm, Germany
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Li X, Chang P, Liu X, Kang Y, Zhao Z, Duan Y, Zhu T, Liu J, Zhang W. A preclinical study on online monitoring of exhaled ciprofol concentration by the ultraviolet time-of-flight spectrometer and prediction of anesthesia depth in beagles. J Pharm Biomed Anal 2023; 235:115621. [PMID: 37572595 DOI: 10.1016/j.jpba.2023.115621] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2023] [Revised: 07/22/2023] [Accepted: 07/31/2023] [Indexed: 08/14/2023]
Abstract
BACKGROUND Exhaled air has been demonstrated as a reliable medium for monitoring propofol concentration. However, online monitoring of exhaled ciprofol have not been reported. METHODS Thirty-six beagles undergoing mechanical ventilation were divided into 6 groups, including bolus injection of low (Group BL, n = 6), medium (Group BM, n = 6), and high dose of ciprofol (Group BH, n = 6) groups; as well as 1 h continuous infusion of low (Group IL, n = 6), medium (Group IM, n = 6), and high dose of ciprofol (Group IH, n = 6) groups. The ciprofol concentration in exhaled air (CE) was determined by the ultraviolet time-of-flight mass spectrometer (UV-TOFMS). The correlations of CE and plasma concentration (Cp), CE and the bispectral index (BIS) were explored. Additionally, the pharmacokinetics (PK) models of CE and Cp, the pharmacodynamics (PD) models of CE and BIS were also established. RESULTS Online monitoring of exhaled ciprofol can be achieved with the UV-TOFMS instrument. The CE of ciprofol in beagles was found at parts per billion by volume (ppbv) level. The linear correlation of CE and Cp was weak in bolus injection groups (R2 = 0.01) nonetheless moderate in continuous infusion groups (R2 = 0.53). The i.v. bolus PK model of CE and Cp can be fitted with the non-compartment models. Additionally, the the PD models of CE and BIS can be well fitted with the inhibitory sigmoid Emax model with the estimate values of IC50 = 0.05 ± 0.01 ppbv, γ = 4.74 ± 1.51, E0 = 81.40 ± 3.75, Imax = 16.35 ± 4.27 in bolus injection groups; and IC50 = 0.05 ± 0.01 ppbv, γ = 6.92 ± 1.30, E0 = 83.08 ± 1.62, Imax = 12.58 ± 1.65 in continuous infusion groups. CONCLUSIONS Online monitoring of exhaled ciprofol concentration in beagles can be achieved with the UV-TOFMS instrument. Good correlations can be observed between exhaled ciprofol concentration and its cerebral effects reflected by the BIS value, demonstrating the potential of exhaled ciprofol monitoring for titrating depth of anesthesia in future clinical setting.
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Affiliation(s)
- Xiaoxiao Li
- Department of Anesthesiology, West China Hospital, Sichuan university, China; Laboratory of Anesthesia and Critical Care Medicine, National-Local Joint Engineering Research Centre of Translational Medicine of Anesthesiology, West China Hospital, Sichuan University, China
| | - Pan Chang
- Department of Anesthesiology, West China Hospital, Sichuan university, China; Laboratory of Anesthesia and Critical Care Medicine, National-Local Joint Engineering Research Centre of Translational Medicine of Anesthesiology, West China Hospital, Sichuan University, China
| | - Xing Liu
- Department of Anesthesiology, West China Hospital, Sichuan university, China; Laboratory of Anesthesia and Critical Care Medicine, National-Local Joint Engineering Research Centre of Translational Medicine of Anesthesiology, West China Hospital, Sichuan University, China
| | - Yi Kang
- Department of Anesthesiology, West China Hospital, Sichuan university, China; Laboratory of Anesthesia and Critical Care Medicine, National-Local Joint Engineering Research Centre of Translational Medicine of Anesthesiology, West China Hospital, Sichuan University, China
| | - Zhongjun Zhao
- School of Mechanical Engineering, Sichuan University, China
| | - Yixiang Duan
- School of Mechanical Engineering, Sichuan University, China
| | - Tao Zhu
- Department of Anesthesiology, West China Hospital, Sichuan university, China; Laboratory of Anesthesia and Critical Care Medicine, National-Local Joint Engineering Research Centre of Translational Medicine of Anesthesiology, West China Hospital, Sichuan University, China
| | - Jin Liu
- Department of Anesthesiology, West China Hospital, Sichuan university, China; Laboratory of Anesthesia and Critical Care Medicine, National-Local Joint Engineering Research Centre of Translational Medicine of Anesthesiology, West China Hospital, Sichuan University, China
| | - Wensheng Zhang
- Department of Anesthesiology, West China Hospital, Sichuan university, China; Laboratory of Anesthesia and Critical Care Medicine, National-Local Joint Engineering Research Centre of Translational Medicine of Anesthesiology, West China Hospital, Sichuan University, China.
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Malagutti N, McGinness G, Nithyanandam DA. Real-Time Personalised Pharmacokinetic-Pharmacodynamic Modelling in Propofol Anesthesia through Bayesian Inference. ANNUAL INTERNATIONAL CONFERENCE OF THE IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. IEEE ENGINEERING IN MEDICINE AND BIOLOGY SOCIETY. ANNUAL INTERNATIONAL CONFERENCE 2023; 2023:1-6. [PMID: 38082840 DOI: 10.1109/embc40787.2023.10339991] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/18/2023]
Abstract
Pharmacological models describe a patient's response to the administration of a medicinal drug based on parameters derived from population studies. However, considerable inter-patient variability exists, such that population models may underperform when used to predict the actual response of a specific individual. In applications which demand predictive accuracy-such as target-controlled infusion of anesthetic agents-modeling uncertainty may reduce system dependability and introduce clinical risk. Our work investigates the use of Bayesian inference, implemented through a particle filter algorithm, to refine a prior model of propofol pharmacokinetics-pharmacodynamics and estimate patient-specific parameters in real-time. We report here on an observational clinical study conducted on 40 adults undergoing general anesthesia, where we evaluated the performance of Bayesian inference-personalized models in forecasting forward trends of depth of anesthesia (Bispectral Index) measurements and compared it with that of a traditional population-based pharmacological model. Our results show a significant reduction in prediction error metrics for the patient-specific models. Our study demonstrates the viability and practical implementability of Bayesian inference as a tool for real-time intra-operative estimation of personalized pharmacological models in anesthesia applications.
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Teucke T, Maurer F, Müller-Wirtz LM, Volk T, Sessler DI, Kreuer S. Humidity and measurement of volatile propofol using MCC-IMS (EDMON). J Clin Monit Comput 2023; 37:493-500. [PMID: 36129642 PMCID: PMC10068632 DOI: 10.1007/s10877-022-00907-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Accepted: 08/08/2022] [Indexed: 10/14/2022]
Abstract
The bedside Exhaled Drug MONitor - EDMON measures exhaled propofol in ppbv every minute based on multi-capillary column - ion mobility spectrometry (MCC-IMS). The MCC pre-separates gas samples, thereby reducing the influence of the high humidity in human breath. However, preliminary analyses identified substantial measurement deviations between dry and humid calibration standards. We therefore performed an analytical validation of the EDMON to evaluate the influence of humidity on measurement performance. A calibration gas generator was used to generate gaseous propofol standards measured by an EDMON device to assess linearity, precision, carry-over, resolution, and the influence of different levels of humidity at 100% and 1.7% (without additional) relative humidity (reference temperature: 37°C). EDMON measurements were roughly half the actual concentration without additional humidity and roughly halved again at 100% relative humidity. Standard concentrations and EDMON values correlated linearly at 100% relative humidity (R²=0.97). The measured values were stable over 100min with a variance ≤ 10% in over 96% of the measurements. Carry-over effects were low with 5% at 100% relative humidity after 5min of equilibration. EDMON measurement resolution at 100% relative humidity was 0.4 and 0.6 ppbv for standard concentrations of 3 ppbv and 41 ppbv. The influence of humidity on measurement performance was best described by a second-order polynomial function (R²≥0.99) with influence reaching a maximum at about 70% relative humidity. We conclude that EDMON measurements are strongly influenced by humidity and should therefore be corrected for sample humidity to obtain accurate estimates of exhaled propofol concentrations.
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Affiliation(s)
- Tobias Teucke
- CBR - Center of Breath Research, Department of Anaesthesiology, Intensive Care and Pain Therapy, Faculty of Medicine, Saarland University Medical Center, Saarland University, 66421, Homburg, Saar, Germany.
| | - F Maurer
- CBR - Center of Breath Research, Department of Anaesthesiology, Intensive Care and Pain Therapy, Faculty of Medicine, Saarland University Medical Center, Saarland University, 66421, Homburg, Saar, Germany
| | - L M Müller-Wirtz
- CBR - Center of Breath Research, Department of Anaesthesiology, Intensive Care and Pain Therapy, Faculty of Medicine, Saarland University Medical Center, Saarland University, 66421, Homburg, Saar, Germany
| | - T Volk
- CBR - Center of Breath Research, Department of Anaesthesiology, Intensive Care and Pain Therapy, Faculty of Medicine, Saarland University Medical Center, Saarland University, 66421, Homburg, Saar, Germany
| | - D I Sessler
- Department of OUTCOMES RESEARCH, Anaesthesiology Institute, Cleveland Clinic, Cleveland, OH, USA
| | - S Kreuer
- CBR - Center of Breath Research, Department of Anaesthesiology, Intensive Care and Pain Therapy, Faculty of Medicine, Saarland University Medical Center, Saarland University, 66421, Homburg, Saar, Germany
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Sajedi-Amin S, Khoubnasabjafari M, Jouyban-Gharamaleki V, Rahimpour E, Jouyban A. Propofol-induced in-situ formation of silver nanoparticles: A sensing colorimetric method. J Pharm Biomed Anal 2023; 229:115377. [PMID: 37018957 DOI: 10.1016/j.jpba.2023.115377] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2022] [Revised: 03/26/2023] [Accepted: 03/29/2023] [Indexed: 04/03/2023]
Abstract
A simple and eco-friendly colorimetric sensing method has been developed for the extremely effective detection of propofol in exhaled breath condensate (EBC). In this study, we put forward a Tollens' procedure, in which silver nanoparticles (AgNPs) were produced using propofol as a reducing agent. To verify the in-situ synthesis of AgNPs, the TEM images, and UV-Vis absorbance were recorded in the absence and presence of propofol. The solution turned from a colorless to yellow and deep yellow color due to the surface plasmon resonance absorption band of formed AgNPs. The intensity of nanoparticle absorbance was quantitatively correlated with the propofol concentration. The proposed sensor revealed good linearity over the range of 0.01-0.8 µg mL-1 at 422 nm with the detection limit of 8.8 ng mL-1 under optimum conditions. Finally, the proposed colorimetric sensor was successfully used for the determination of propofol in the EBC sample of patients receiving propofol.
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Affiliation(s)
- Sanaz Sajedi-Amin
- Pharmaceutical Analysis Research Center and Faculty of Pharmacy, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Maryam Khoubnasabjafari
- Tuberculosis and Lung Diseases Research Center, Tabriz University of Medical Sciences, Tabriz, Iran; Department of Anesthesiology and Intensive Care, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Vahid Jouyban-Gharamaleki
- Kimia Idea Pardaz Azarbayjan (KIPA) Science Based Company, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Elaheh Rahimpour
- Pharmaceutical Analysis Research Center and Faculty of Pharmacy, Tabriz University of Medical Sciences, Tabriz, Iran; Infectious and Tropical Diseases Research Center, Tabriz University of Medical Sciences, 5165665811, Tabriz, Iran.
| | - Abolghasem Jouyban
- Pharmaceutical Analysis Research Center and Faculty of Pharmacy, Tabriz University of Medical Sciences, Tabriz, Iran; Pharmaceutical Sciences Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran
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Braathen MR, Rimstad I, Dybvik T, Nygård S, Ræder J. Online exhaled propofol monitoring in normal-weight and obese surgical patients. Acta Anaesthesiol Scand 2022; 66:598-605. [PMID: 35138633 PMCID: PMC9305953 DOI: 10.1111/aas.14043] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2021] [Revised: 01/20/2022] [Accepted: 02/03/2022] [Indexed: 12/27/2022]
Abstract
Background Ion mobility spectrometry (IMS) allows for online quantification of exhaled propofol concentrations. We aimed to validate a bedside online IMS device, the Edmon®, for predicting plasma concentrations of propofol in normal‐weight and obese patients. Methods Patients with body mass index (BMI) >20 kg/m2 scheduled for laparoscopic cholecystectomy or bariatric surgery were recruited. Exhaled propofol concentrations (CA), arterial plasma propofol concentrations (CP) and bispectral index (BIS) values were collected during target‐controlled infusion (TCI) anaesthesia. Generalised estimation equation (GEE) was applied to all samples and stable‐phase samples at different delays for best fit between CP and CA. BMI was evaluated as covariate. BIS and exhaled propofol correlations were also assessed with GEE. Results A total of 29 patients (BMI 20.3–53.7) were included. A maximal R2 of 0.58 was found during stable concentrations with 5 min delay of CA to CP; the intercept a = −0.69 (95% CI −1.7, 0.3) and slope b = 0.87 (95% CI 0.7, 1.1). BMI was found to be a non‐significant covariate. The median absolute performance error predicting plasma propofol concentrations was 13.4%. At a CA of 5 ppb, the model predicts a CP of 3.6 μg/ml (95% CI ±1.4). There was a maximal negative correlation of R2 = 0.44 at 2‐min delay from CA to BIS. Conclusions Online monitoring of exhaled propofol concentrations is clinically feasible in normal‐weight and obese patients. With a 5‐min delay, our model outperforms the Marsh plasma TCI model in a post hoc analysis. Modest correlation with plasma concentrations makes the clinical usefulness questionable.
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Affiliation(s)
- Martin R. Braathen
- Institute of Clinical Medicine Faculty of Medicine University of Oslo Oslo Norway
- Department of Anaesthesiology Division of Critical Care Oslo University Hospital Oslo Norway
| | - Ivan Rimstad
- Institute of Clinical Medicine Faculty of Medicine University of Oslo Oslo Norway
- Department of Anaesthesiology Division of Critical Care Oslo University Hospital Oslo Norway
| | - Terje Dybvik
- Department of Anaesthesiology Division of Critical Care Oslo University Hospital Oslo Norway
| | - Ståle Nygård
- Department of Informatics Faculty of Mathematics and Natural Sciences University of Oslo Oslo Norway
- Department of Biostatistics Institute of Basic Medical Sciences Oslo Centre for Biostatistics and Epidemiology University of Oslo Oslo Norway
| | - Johan Ræder
- Institute of Clinical Medicine Faculty of Medicine University of Oslo Oslo Norway
- Department of Anaesthesiology Division of Critical Care Oslo University Hospital Oslo Norway
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Yang X, Zhang T, Yang D, Xie J. Application of gas chromatography-ion mobility spectrometry in the analysis of food volatile components. ACTA CHROMATOGR 2022. [DOI: 10.1556/1326.2022.01005] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
Abstract
Gas chromatography-ion mobility spectrometry (GC-IMS) is an emerging analytical technique that has the advantages of fast response, high sensitivity, simple operation, and low cost. The combination of the fast speed and resolution of GC with the high sensitivity of IMS makes GC-IMS play an important role in the detection of food volatile substances. This paper focuses on the basic principles and future development trend, and the comparative analysis of the functions, similarities and differences of GC-IMS, GC-MS and electronic nose in the detection of common volatile compounds. A comprehensive introduction to the main application of GC-IMS in food volatile components: fingerprint identification of sample differences and detection of characteristic compounds. On the basis of perfecting the spectral library, GC-IMS will have broad development prospects in food authentication, origin identification, process optimization and product classification, especially in the analysis and identification of trace volatile food flavor substances.
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Affiliation(s)
- Xuelian Yang
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, Beijing Technology and Business University, Beijing, 100048, China
- Beijing Engineering and Technology Research Center of Food Additives, Beijing Technology and Business University, Beijing, 100048, China
- Beijing Technology and Business University, Beijing, 100048, China
| | - Tianxin Zhang
- Beijing Technology and Business University, Beijing, 100048, China
| | - Dongdong Yang
- Beijing Technology and Business University, Beijing, 100048, China
| | - Jianchun Xie
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, Beijing Technology and Business University, Beijing, 100048, China
- Beijing Engineering and Technology Research Center of Food Additives, Beijing Technology and Business University, Beijing, 100048, China
- Beijing Technology and Business University, Beijing, 100048, China
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Ferrier DC, Kiely J, Luxton R. Propofol detection for monitoring of intravenous anaesthesia: a review. J Clin Monit Comput 2021; 36:315-323. [PMID: 34213720 PMCID: PMC9123036 DOI: 10.1007/s10877-021-00738-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/04/2020] [Accepted: 06/28/2021] [Indexed: 11/03/2022]
Abstract
This paper presents a review of established and emerging methods for detecting and quantifying the intravenous anaesthetic propofol in solution. There is growing evidence of numerous advantages of total intravenous anaesthesia using propofol compared to conventional volatile-based anaesthesia, both in terms of patient outcomes and environmental impact. However, volatile-based anaesthesia still accounts for the vast majority of administered general anaesthetics, largely due to a lack of techniques for real-time monitoring of patient blood propofol concentration. Herein, propofol detection techniques that have been developed to date are reviewed alongside a discussion of remaining challenges.
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Affiliation(s)
- David C Ferrier
- Institute of Bio-Sensing Technology, University of the West of England, Frenchay Campus, Bristol, BS16 1QY, UK.
| | - Janice Kiely
- Institute of Bio-Sensing Technology, University of the West of England, Frenchay Campus, Bristol, BS16 1QY, UK
| | - Richard Luxton
- Institute of Bio-Sensing Technology, University of the West of England, Frenchay Campus, Bristol, BS16 1QY, UK
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Heiderich S, Ghasemi T, Dennhardt N, Sümpelmann R, Rigterink V, Nickel K, Keil O, Böthig D, Beck CE. Correlation of exhaled propofol with Narcotrend index and calculated propofol plasma levels in children undergoing surgery under total intravenous anesthesia - an observational study. BMC Anesthesiol 2021; 21:161. [PMID: 34039280 PMCID: PMC8149920 DOI: 10.1186/s12871-021-01368-9] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2021] [Accepted: 05/04/2021] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Exhaled propofol concentrations correlate with propofol concentrations in adult human blood and the brain tissue of rats, as well as with electroencephalography (EEG) based indices of anesthetic depth. The pharmacokinetics of propofol are however different in children compared to adults. The value of exhaled propofol measurements in pediatric anesthesia has not yet been investigated. Breathing system filters and breathing circuits can also interfere with the measurements. In this study, we investigated correlations between exhaled propofol (exP) concentrations and the Narkotrend Index (NI) as well as calculated propofol plasma concentrations. METHODS A multi-capillary-column (MCC) combined with ion mobility spectrometry (IMS) was used to determine exP. Optimal positioning of breathing system filters (near-patient or patient-distant) and sample line (proximal or distal to filter) were investigated. Measurements were taken during induction (I), maintenance (M) and emergence (E) of children under total intravenous anesthesia (TIVA). Correlations between ExP concentrations and NI and predicted plasma propofol concentrations (using pediatric pharmacokinetic models Kataria and Paedfusor) were assessed using Pearson correlation and regression analysis. RESULTS Near-patient positioning of breathing system filters led to continuously rising exP values when exP was measured proximal to the filters, and lower concentrations when exP was measured distal to the filters. The breathing system filters were therefore subsequently attached between the breathing system tubes and the inspiratory and expiratory limbs of the anesthetic machine. ExP concentrations significantly correlated with NI and propofol concentrations predicted by pharmacokinetic models during induction and maintenance of anesthesia. During emergence, exP significantly correlated with predicted propofol concentrations, but not with NI. CONCLUSION In this study, we demonstrated that exP correlates with calculated propofol concentrations and NI during induction and maintenance in pediatric patients. However, the correlations are highly variable and there are substantial obstacles: Without patient proximal placement of filters, the breathing circuit tubing must be changed after each patient, and furthermore, during ventilation, a considerable additional loss of heat and moisture can occur. Adhesion of propofol to plastic parts (endotracheal tube, breathing circle) may especially be problematic during emergence. TRIAL REGISTRATION The study was registered in the German registry of clinical studies (DRKS-ID: DRKS00015795 ).
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Affiliation(s)
- Sebastian Heiderich
- Clinic of Anesthesiology and Intensive Care Medicine, Hannover Medical School, Carl-Neuberg-Str. 1, 30625, Hannover, Germany.
| | - Tara Ghasemi
- Clinic of Anesthesiology and Intensive Care Medicine, Hannover Medical School, Carl-Neuberg-Str. 1, 30625, Hannover, Germany
| | - Nils Dennhardt
- Clinic of Anesthesiology and Intensive Care Medicine, Hannover Medical School, Carl-Neuberg-Str. 1, 30625, Hannover, Germany
| | - Robert Sümpelmann
- Clinic of Anesthesiology and Intensive Care Medicine, Hannover Medical School, Carl-Neuberg-Str. 1, 30625, Hannover, Germany
| | - Vanessa Rigterink
- Clinic of Anesthesiology and Intensive Care Medicine, Hannover Medical School, Carl-Neuberg-Str. 1, 30625, Hannover, Germany
| | - Katja Nickel
- Clinic of Anesthesiology and Intensive Care Medicine, Hannover Medical School, Carl-Neuberg-Str. 1, 30625, Hannover, Germany
| | - Oliver Keil
- Clinic of Anesthesiology and Intensive Care Medicine, Hannover Medical School, Carl-Neuberg-Str. 1, 30625, Hannover, Germany
| | - Dietmar Böthig
- Department for Pediatric Cardiology and Intensive Care, Hannover Medical School, Hannover, Germany
| | - Christiane E Beck
- Clinic of Anesthesiology and Intensive Care Medicine, Hannover Medical School, Carl-Neuberg-Str. 1, 30625, Hannover, Germany
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Quantification of Volatile Aldehydes Deriving from In Vitro Lipid Peroxidation in the Breath of Ventilated Patients. Molecules 2021; 26:molecules26113089. [PMID: 34064214 PMCID: PMC8196825 DOI: 10.3390/molecules26113089] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2021] [Revised: 05/14/2021] [Accepted: 05/19/2021] [Indexed: 01/18/2023] Open
Abstract
Exhaled aliphatic aldehydes were proposed as non-invasive biomarkers to detect increased lipid peroxidation in various diseases. As a prelude to clinical application of the multicapillary column–ion mobility spectrometry for the evaluation of aldehyde exhalation, we, therefore: (1) identified the most abundant volatile aliphatic aldehydes originating from in vitro oxidation of various polyunsaturated fatty acids; (2) evaluated emittance of aldehydes from plastic parts of the breathing circuit; (3) conducted a pilot study for in vivo quantification of exhaled aldehydes in mechanically ventilated patients. Pentanal, hexanal, heptanal, and nonanal were quantifiable in the headspace of oxidizing polyunsaturated fatty acids, with pentanal and hexanal predominating. Plastic parts of the breathing circuit emitted hexanal, octanal, nonanal, and decanal, whereby nonanal and decanal were ubiquitous and pentanal or heptanal not being detected. Only pentanal was quantifiable in breath of mechanically ventilated surgical patients with a mean exhaled concentration of 13 ± 5 ppb. An explorative analysis suggested that pentanal exhalation is associated with mechanical power—a measure for the invasiveness of mechanical ventilation. In conclusion, exhaled pentanal is a promising non-invasive biomarker for lipid peroxidation inducing pathologies, and should be evaluated in future clinical studies, particularly for detection of lung injury.
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Jiang D, Chen C, Wang W, Wang W, Li M, Wang X, Liu Y, Li E, Li H. Breath-by-breath measurement of intraoperative propofol by unidirectional anisole-assisted photoionization ion mobility spectrometry via real-time correction of humidity. Anal Chim Acta 2021; 1150:338223. [PMID: 33583551 DOI: 10.1016/j.aca.2021.338223] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2020] [Revised: 01/15/2021] [Accepted: 01/16/2021] [Indexed: 12/29/2022]
Abstract
Humidity as a major issue affects the quantitative performance of ion mobility spectrometry (IMS) in field applications. According to the kinetic equations of ion-molecular reaction, the intensity ratio of the product ion peak (PIP) over the reactant ion peak (RIP) is proposed as a quantitative factor to correct real-time humidity variation. By coupling this method with a unidirectional anisole-assisted photoionization IMS, direct breath-by-breath measurement of intraoperative propofol was achieved for the first time, which provided more clinical information for studying the anesthetics pharmacokinetics. Although the signal intensities of the RIP and the propofol PIP both declined along with the increase of humidity, the intensity ratio of Propofol/(RIP + Propofol) kept almost constant in a wide relative humidity range of 0%-98%, enabling direct quantitation of exhaled propofol with varying humidity. Furthermore, interfering ion peaks resulted from the high concentration humidity and anesthetics in single exhalation were eliminated during the balanced anesthesia as the exhaled sample was diluted by the unidirectional gas flow scheme. As a demonstration, breath-by-breath variation profiles of propofol were obtained via monitoring end-tidal propofol concentration of intraoperative anesthetized patients (n = 7). The analyses were quantitative, corrected for humidity in real-time, without measuring the humidity content of each breath sample during operation, which show potential for the quantitative analysis of other high humidity samples.
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Affiliation(s)
- Dandan Jiang
- CAS Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, Liaoning, 116023, People's Republic of China
| | - Chuang Chen
- CAS Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, Liaoning, 116023, People's Republic of China
| | - Weimin Wang
- CAS Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, Liaoning, 116023, People's Republic of China; University of Chinese Academy of Sciences, Beijing, 100049, People's Republic of China
| | - Weiguo Wang
- CAS Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, Liaoning, 116023, People's Republic of China
| | - Mei Li
- CAS Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, Liaoning, 116023, People's Republic of China; University of Chinese Academy of Sciences, Beijing, 100049, People's Republic of China
| | - Xin Wang
- CAS Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, Liaoning, 116023, People's Republic of China
| | - Yiping Liu
- Department of Anesthesiology, The First Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang, 150001, People's Republic of China
| | - Enyou Li
- Department of Anesthesiology, The First Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang, 150001, People's Republic of China
| | - Haiyang Li
- CAS Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, Liaoning, 116023, People's Republic of China.
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Müller-Wirtz LM, Maurer F, Brausch T, Kiefer D, Floss M, Doneit J, Volk T, Sessler DI, Fink T, Lehr T, Kreuer S. Exhaled Propofol Concentrations Correlate With Plasma and Brain Tissue Concentrations in Rats. Anesth Analg 2021; 132:110-118. [PMID: 32118620 DOI: 10.1213/ane.0000000000004701] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
BACKGROUND Propofol can be measured in exhaled gas. Exhaled and plasma propofol concentrations correlate well, but the relationship with tissue concentrations remains unknown. We thus evaluated the relationship between exhaled, plasma, and various tissue propofol concentrations. Because the drug acts in the brain, we focused on the relationship between exhaled and brain tissue propofol concentrations. METHODS Thirty-six male Sprague-Dawley rats were anesthetized with propofol, ketamine, and rocuronium for 6 hours. Animals were randomly assigned to propofol infusions at 20, 40, or 60 mg·kg·h (n = 12 per group). Exhaled propofol concentrations were measured at 15-minute intervals by multicapillary column-ion mobility spectrometry. Arterial blood samples, 110 µL each, were collected 15, 30, and 45 minutes, and 1, 2, 4, and 6 hours after the propofol infusion started. Propofol concentrations were measured in brain, lung, liver, kidney, muscle, and fat tissue after 6 hours. The last exhaled and plasma concentrations were used for linear regression analyses with tissue concentrations. RESULTS The correlation of exhaled versus plasma concentrations (R = 0.71) was comparable to the correlation of exhaled versus brain tissue concentrations (R = 0.75) at the end of the study. In contrast, correlations between plasma and lung and between lung and exhaled propofol concentrations were poor. Less than a part-per-thousand of propofol was exhaled over 6 hours. CONCLUSIONS Exhaled propofol concentrations correlate reasonably well with brain tissue and plasma concentrations in rats, and may thus be useful to estimate anesthetic drug effect. The equilibration between plasma propofol and exhaled gas is apparently independent of lung tissue concentration. Only a tiny fraction of administered propofol is eliminated via the lungs, and exhaled quantities thus have negligible influence on plasma concentrations.
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Affiliation(s)
- Lukas M Müller-Wirtz
- From the Department of Anesthesiology, Intensive Care and Pain Therapy, Center of Breath Research, Saarland University Medical Center, Homburg (Saar), Germany
| | - Felix Maurer
- From the Department of Anesthesiology, Intensive Care and Pain Therapy, Center of Breath Research, Saarland University Medical Center, Homburg (Saar), Germany
| | - Timo Brausch
- From the Department of Anesthesiology, Intensive Care and Pain Therapy, Center of Breath Research, Saarland University Medical Center, Homburg (Saar), Germany
| | - Daniel Kiefer
- From the Department of Anesthesiology, Intensive Care and Pain Therapy, Center of Breath Research, Saarland University Medical Center, Homburg (Saar), Germany
| | - Maximilian Floss
- From the Department of Anesthesiology, Intensive Care and Pain Therapy, Center of Breath Research, Saarland University Medical Center, Homburg (Saar), Germany
| | - Jonas Doneit
- From the Department of Anesthesiology, Intensive Care and Pain Therapy, Center of Breath Research, Saarland University Medical Center, Homburg (Saar), Germany
| | - Thomas Volk
- From the Department of Anesthesiology, Intensive Care and Pain Therapy, Center of Breath Research, Saarland University Medical Center, Homburg (Saar), Germany
| | - Daniel I Sessler
- Department of Outcomes Research, Anesthesiology Institute, Cleveland Clinic, Cleveland, Ohio
| | - Tobias Fink
- From the Department of Anesthesiology, Intensive Care and Pain Therapy, Center of Breath Research, Saarland University Medical Center, Homburg (Saar), Germany
| | - Thorsten Lehr
- Clinical Pharmacy, Department of Pharmacy, Saarland University, Saarbrücken, Germany. The Center of Breath Research is part of the Outcomes Research Consortium, Cleveland, Ohio, USA
| | - Sascha Kreuer
- From the Department of Anesthesiology, Intensive Care and Pain Therapy, Center of Breath Research, Saarland University Medical Center, Homburg (Saar), Germany
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Ahrens A, Möhle J, Hitzemann M, Zimmermann S. Novel ion drift tube for high-performance ion mobility spectrometers based on a composite material. ACTA ACUST UNITED AC 2020. [DOI: 10.1007/s12127-020-00265-0] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
AbstractIon mobility spectrometers (IMS) are able to detect pptV-level concentrations of substances in gasses and in liquids within seconds. Due to the continuous increase in analytical performance and reduction of the instrument size, IMS are established nowadays in a variety of analytical field applications. In order to reduce the manufacturing effort and further enhance their widespread use, we have developed a simple manufacturing process for drift tubes based on a composite material. This composite material consists of alternating layers of metal sheets and insulator material, which are connected to each other in a mechanically stable and gastight manner. Furthermore, this approach allows the production of ion drift tubes in just a few steps from a single piece of material, thus reducing the manufacturing costs and efforts. Here, a drift tube ion mobility spectrometer based on such a composite material is presented. Although its outer dimensions are just 15 mm × 15 mm in cross section and 57 mm in length, it has high resolving power of Rp = 62 and detection limits in the pptV-range, demonstrated for ethanol and 1,2,3-trichloropropane.
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The role of pharmacokinetics and pharmacodynamics in clinical anaesthesia practice. Curr Opin Anaesthesiol 2020; 33:483-489. [DOI: 10.1097/aco.0000000000000881] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
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17
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Jiang D, Chen C, Wang X, Li M, Xiao Y, Liu Y, Li E, Li H. Online monitoring of end-tidal propofol in balanced anesthesia by anisole assisted positive photoionization ion mobility spectrometer. Talanta 2020; 211:120712. [DOI: 10.1016/j.talanta.2020.120712] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2019] [Revised: 12/28/2019] [Accepted: 01/02/2020] [Indexed: 01/26/2023]
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18
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FAN XS, FAN XD, FENG XM, LI CC, BI CY, LI J, YIN JY, HAN YC. Facile Determination of Anesthetic Drug Propofol Based on Electrochemiluminescence Quenching. CHINESE JOURNAL OF ANALYTICAL CHEMISTRY 2020. [DOI: 10.1016/s1872-2040(20)60011-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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19
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Malásková M, Olivenza-León D, Chellayah PD, Martini J, Lederer W, Ruzsanyi V, Unterkofler K, Mochalski P, Märk TD, Watts P, Mayhew CA. Studies pertaining to the monitoring of volatile halogenated anaesthetics in breath by proton transfer reaction mass spectrometry. J Breath Res 2020; 14:026004. [PMID: 31796655 DOI: 10.1088/1752-7163/ab5e30] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
Post-operative isoflurane has been observed to be present in the end-tidal breath of patients who have undergone major surgery, for several weeks after the surgical procedures. A major new non-controlled, non-randomized, and open-label approved study will recruit patients undergoing various surgeries under different inhalation anaesthetics, with two key objectives, namely (1) to record the washout characteristics following surgery, and (2) to investigate the influence of a patient's health and the duration and type of surgery on elimination. In preparation for this breath study using proton transfer reaction time-of-flight mass spectrometry (PTR-TOF-MS), it is important to identify first the analytical product ions that need to be monitored and under what operating conditions. In this first paper of this new research programme, we present extensive PTR-TOF-MS studies of three major anaesthetics used worldwide, desflurane (CF3CHFOCHF2), sevoflurane ((CF3)2CHOCH2F), and isoflurane (CF3CHClOCHF2) and a fourth one, which is used less extensively, enflurane (CHF2OCF2CHFCl), but is of interest because it is an isomer of isoflurane. Product ions are identified as a function of reduced electric field (E/N) over the range of approximately 80 Td to 210 Td, and the effects of operating the drift tube under 'normal' or 'humid' conditions on the intensities of the product ions are presented. To aid in the analyses, density functional theory (DFT) calculations of the proton affinities and the gas-phase basicities of the anaesthetics have been determined. Calculated energies for the ion-molecule reaction pathways leading to key product ions, identified as ideal for monitoring the inhalation anaesthetics in breath with a high sensitivity and selectivity, are also presented.
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Affiliation(s)
- Michaela Malásková
- Institute for Breath Research, Leopold-Franzens-Universität Innsbruck, Rathausplatz 4, A 6850, Dornbirn, Austria
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20
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Kruizinga MD, Birkhoff WAJ, van Esdonk MJ, Klarenbeek NB, Cholewinski T, Nelemans T, Dröge MJ, Cohen AF, Zuiker RGJA. Pharmacokinetics of intravenous and inhaled salbutamol and tobramycin: An exploratory study to investigate the potential of exhaled breath condensate as a matrix for pharmacokinetic analysis. Br J Clin Pharmacol 2020; 86:175-181. [PMID: 31658494 PMCID: PMC6983506 DOI: 10.1111/bcp.14156] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2019] [Revised: 10/11/2019] [Accepted: 10/15/2019] [Indexed: 12/17/2022] Open
Abstract
Concentrations of drugs acting in the lungs are difficult to measure, resulting in relatively unknown local pharmacokinetics. The aim of this study is to assess the potential of exhaled breath condensate (EBC) as a matrix for pharmacokinetic analysis of inhaled and intravenous medication. A 4‐way crossover study was conducted in 12 volunteers with tobramycin and salbutamol intravenously and via inhalation. EBC and plasma samples were collected postdose and analysed for drug concentrations. Sample dilution, calculated using urea concentrations, was used to estimate the epithelial lining fluid concentration. Salbutamol and tobramycin were largely undetectable in EBC after intravenous administration and were detectable after inhaled administration in all subjects in 50.8 and 51.5% of EBC samples, respectively. Correction of EBC concentrations for sample dilution did not explain the high variability. This high variability of EBC drug concentrations seems to preclude EBC as a matrix for pharmacokinetic analysis of tobramycin and salbutamol.
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Affiliation(s)
| | | | - Michiel J van Esdonk
- Centre for Human Drug Research, Leiden, the Netherlands.,Division of Systems Biomedicine and Pharmacology, Leiden Academic Centre for Drug Research, Leiden University, Leiden, the Netherlands
| | | | | | | | | | - Adam F Cohen
- Centre for Human Drug Research, Leiden, the Netherlands
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Development of a LC–MS/MS method for determination of propofol-glucuronide in hair and preliminary study on relationships between dose and hair concentration. Forensic Sci Int 2020; 306:110070. [DOI: 10.1016/j.forsciint.2019.110070] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2019] [Revised: 11/14/2019] [Accepted: 11/15/2019] [Indexed: 11/22/2022]
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22
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Possible strategy to use differential mobility spectrometry in real time applications. ACTA ACUST UNITED AC 2019. [DOI: 10.1007/s12127-019-00251-1] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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23
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Ahrens A, Hitzemann M, Zimmermann S. Miniaturized high-performance drift tube ion mobility spectrometer. ACTA ACUST UNITED AC 2019. [DOI: 10.1007/s12127-019-00248-w] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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24
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Detecting Early Markers of Ventilator-Associated Pneumonia by Analysis of Exhaled Gas. Crit Care Med 2019; 47:e234-e240. [DOI: 10.1097/ccm.0000000000003573] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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25
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Metternich S, Zörntlein S, Schönberger T, Huhn C. Ion mobility spectrometry as a fast screening tool for synthetic cannabinoids to uncover drug trafficking in jail via herbal mixtures, paper, food, and cosmetics. Drug Test Anal 2019; 11:833-846. [DOI: 10.1002/dta.2565] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2018] [Revised: 12/30/2018] [Accepted: 12/30/2018] [Indexed: 01/25/2023]
Affiliation(s)
- Sonja Metternich
- State Office of Criminal Investigation Rhineland‐PalatinateDepartment of Forensic Science Mainz Germany
| | - Siegfried Zörntlein
- State Office of Criminal Investigation Rhineland‐PalatinateDepartment of Forensic Science Mainz Germany
| | | | - Carolin Huhn
- Eberhard Karls Universität TübingenInstitute for Physical and Theoretical Chemistry Tübingen Germany
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26
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Hyphenation of a MEMS based pre-concentrator and GC-IMS. Talanta 2019; 191:141-148. [DOI: 10.1016/j.talanta.2018.07.057] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2018] [Revised: 07/17/2018] [Accepted: 07/18/2018] [Indexed: 11/18/2022]
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27
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Vautz W, Franzke J, Zampolli S, Elmi I, Liedtke S. On the potential of ion mobility spectrometry coupled to GC pre-separation – A tutorial. Anal Chim Acta 2018; 1024:52-64. [DOI: 10.1016/j.aca.2018.02.052] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/25/2017] [Revised: 02/16/2018] [Accepted: 02/19/2018] [Indexed: 12/14/2022]
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Bergen I, Liedtke S, Güssgen S, Kayser O, Hariharan C, Drees C, Vautz W. Calibration of complex mixtures in one sweep. ACTA ACUST UNITED AC 2018. [DOI: 10.1007/s12127-018-0236-0] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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29
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Liedtke S, Seifert L, Ahlmann N, Hariharan C, Franzke J, Vautz W. Coupling laser desorption with gas chromatography and ion mobility spectrometry for improved olive oil characterisation. Food Chem 2018; 255:323-331. [DOI: 10.1016/j.foodchem.2018.01.193] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2017] [Revised: 01/30/2018] [Accepted: 01/31/2018] [Indexed: 01/27/2023]
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30
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Jiang D, Wang X, Chen C, Wang W, Guo L, Lv Y, Li E, Li H. Dopant-assisted photoionization positive ion mobility spectrometry coupled with time-resolved purge introduction for online quantitative monitoring of intraoperative end-tidal propofol. Anal Chim Acta 2018; 1032:83-90. [PMID: 30143225 DOI: 10.1016/j.aca.2018.06.047] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2018] [Revised: 05/31/2018] [Accepted: 06/14/2018] [Indexed: 12/12/2022]
Abstract
Online monitoring of end-tidal propofol provides important information of anesthesia deepness for anesthetists as propofol concentrations in plasma and breath are well correlated. In this work, a dopant-assisted photoionization positive ion mobility spectrometry (DAPI-PIMS) coupled with time-resolved purge introduction was developed for online quantitative monitoring end-tidal propofol. With optimized dopant, toluene, the selectivity and sensitivity of propofol was improved as interference from sevoflurane was eliminated. Using the time-resolved purge introduction, the response of propofol and moisture was separated due to their absorption differences on the inwall of the fluorinated ethylene propylene (FEP) sample loop, ensuring sensitive measurement of end-tidal propofol with a short response time of 4 s. The quantitative equation derived from the second order reaction kinetics model extended the quantitative range of propofol from 0.2 ppbv to 45 ppbv. Finally, the method was used to monitor the intraoperative end-tidal propofol of six patients, and the results nicely demonstrated its feasibility in practical clinical environment.
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Affiliation(s)
- Dandan Jiang
- CAS Key Laboratory of Separation Sciences for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, Liaoning, 116023, People's Republic of China; University of Chinese Academy of Sciences, Beijing, 100049, People's Republic of China
| | - Xin Wang
- CAS Key Laboratory of Separation Sciences for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, Liaoning, 116023, People's Republic of China
| | - Chuang Chen
- CAS Key Laboratory of Separation Sciences for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, Liaoning, 116023, People's Republic of China
| | - Weiguo Wang
- CAS Key Laboratory of Separation Sciences for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, Liaoning, 116023, People's Republic of China
| | - Lei Guo
- Department of Anesthesiology, The First Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang, 150001, People's Republic of China
| | - Yang Lv
- Department of Anesthesiology, The First Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang, 150001, People's Republic of China
| | - Enyou Li
- Department of Anesthesiology, The First Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang, 150001, People's Republic of China
| | - Haiyang Li
- CAS Key Laboratory of Separation Sciences for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, Liaoning, 116023, People's Republic of China.
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Metabolic Profiles of Propofol and Fospropofol: Clinical and Forensic Interpretative Aspects. BIOMED RESEARCH INTERNATIONAL 2018; 2018:6852857. [PMID: 29992157 PMCID: PMC5994321 DOI: 10.1155/2018/6852857] [Citation(s) in RCA: 46] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Revised: 03/27/2018] [Accepted: 04/15/2018] [Indexed: 02/08/2023]
Abstract
Propofol is an intravenous short-acting anesthetic widely used to induce and maintain general anesthesia and to provide procedural sedation. The potential for propofol dependency and abuse has been recognized, and several cases of accidental overdose and suicide have emerged, mostly among the health professionals. Different studies have demonstrated an unpredictable interindividual variability of propofol pharmacokinetics and pharmacodynamics with forensic and clinical adverse relevant outcomes (e.g., pronounced respiratory and cardiac depression), namely, due to polymorphisms in the UDP-glucuronosyltransferase and cytochrome P450 isoforms and drugs administered concurrently. In this work the pharmacokinetics of propofol and fospropofol with particular focus on metabolic pathways is fully reviewed. It is concluded that knowing the metabolism of propofol may lead to the development of new clues to help further toxicological and clinical interpretations and to reduce serious adverse reactions such as respiratory failure, metabolic acidosis, rhabdomyolysis, cardiac bradyarrhythmias, hypotension and myocardial failure, anaphylaxis, hypertriglyceridemia, renal failure, hepatomegaly, hepatic steatosis, acute pancreatitis, abuse, and death. Particularly, further studies aiming to characterize polymorphic enzymes involved in the metabolic pathway, the development of additional routine forensic toxicological analysis, and the relatively new field of ‘‘omics” technology, namely, metabolomics, can offer more in explaining the unpredictable interindividual variability.
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Vautz W, Hariharan C, Weigend M. Smell the change: On the potential of gas-chromatographic ion mobility spectrometry in ecosystem monitoring. Ecol Evol 2018; 8:4370-4377. [PMID: 29760879 PMCID: PMC5938450 DOI: 10.1002/ece3.3990] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2017] [Revised: 01/23/2018] [Accepted: 02/09/2018] [Indexed: 01/20/2023] Open
Abstract
Plant volatile organic compounds (pVOCs) are being recognized as an important factor in plant–environment interactions. Both the type and amount of the emissions appear to be heavily affected by climate change. A range of studies therefore has been directed toward understanding pVOC emissions, mostly under laboratory conditions (branch/leaf enclosure). However, there is a lack of rapid, sensitive, and selective analytical methods, and therefore, only little is known about VOC emissions under natural, outdoor conditions. An increased sensitivity and the identification of taxon‐specific patterns could turn VOC analysis into a powerful tool for the monitoring of atmospheric chemistry, ecosystems, and biodiversity, with far‐reaching relevance to the impact of climate change on pVOCs and vice versa. This study for the first time investigates the potential of ion mobility spectrometry coupled to gas‐chromatographic preseparation (GC‐IMS) to dramatically increase sensitivity and selectivity for continuous monitoring of pVOCs and to discriminate contributing plant taxa and their phenology. Leaf volatiles were analyzed for nine different common herbaceous plants from Germany. Each plant turned out to have a characteristic metabolite pattern. pVOC patterns in the field would thus reflect the composition of the vegetation, but also phenology (with herbaceous and deciduous plants contributing according to season). The technique investigated here simultaneously enables the identification and quantification of substances characteristic for environmental pollution such as industrial and traffic emissions or pesticides. GC‐IMS thus has an enormous potential to provide a broad range of data on ecosystem function. This approach with near‐continues measurements in the real plant communities could provide crucial insights on pVOC‐level emissions and their relation to climate and phenology and thus provide a sound basis for modeling climate change scenarios including pVOC emissions.
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Affiliation(s)
- Wolfgang Vautz
- Leibniz-Institut für Analytische Wissenschaften - ISAS - e.V. Dortmund Germany.,ION-GAS GmbH Dortmund Germany
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Jiang D, Li E, Zhou Q, Wang X, Li H, Ju B, Guo L, Liu D, Li H. Online Monitoring of Intraoperative Exhaled Propofol by Acetone-Assisted Negative Photoionization Ion Mobility Spectrometry Coupled with Time-Resolved Purge Introduction. Anal Chem 2018; 90:5280-5289. [DOI: 10.1021/acs.analchem.8b00171] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Affiliation(s)
- Dandan Jiang
- CAS Key Laboratory of Separation Sciences for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, Liaoning 116023, People’s Republic of China
- University of Chinese Academy of Sciences, Beijing, 100049, People’s Republic of China
| | - Enyou Li
- Department of Anesthesiology, The First Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang 150001, People’s Republic of China
| | - Qinghua Zhou
- CAS Key Laboratory of Separation Sciences for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, Liaoning 116023, People’s Republic of China
- University of Chinese Academy of Sciences, Beijing, 100049, People’s Republic of China
| | - Xin Wang
- CAS Key Laboratory of Separation Sciences for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, Liaoning 116023, People’s Republic of China
| | - Hanwei Li
- College of Instrumentation & Electrical Engineering, Jilin University, Changchun, Jilin 130026, People’s Republic of China
| | - Bangyu Ju
- CAS Key Laboratory of Separation Sciences for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, Liaoning 116023, People’s Republic of China
| | - Lei Guo
- Department of Anesthesiology, The First Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang 150001, People’s Republic of China
| | - Desheng Liu
- Department of Anesthesiology, The First Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang 150001, People’s Republic of China
| | - Haiyang Li
- CAS Key Laboratory of Separation Sciences for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, Liaoning 116023, People’s Republic of China
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Mochalski P, Ruzsanyi V, Wiesenhofer H, Mayhew CA. Instrumental sensing of trace volatiles-a new promising tool for detecting the presence of entrapped or hidden people. J Breath Res 2018; 12:027107. [PMID: 29091047 DOI: 10.1088/1752-7163/aa9769] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
There is a growing demand for rapid analytical systems to detect the presence of humans who are either entrapped as a result of a disaster or, in particular, hidden, as in the case of smuggling or trafficking. The trafficking and smuggling of people to Europe have reached epidemic proportions in recent years. This does not only put a major strain on European resources, but puts at risk the health and lives of the people being trafficked or smuggled. In this context, the early detection and interception of smuggled/trafficked people is of particular importance in terms of saving migrants from life-threatening situations. Similarly, the early and rapid location of entrapped people is crucial for urban search and rescue (USaR) operations organized after natural or man-made disasters. Since the duration of entrapment determines the survivability of victims, each novel detecting tool could considerably improve the effectiveness of the rescue operations and hence potentially save lives. Chemical analysis aiming at using a volatile chemical fingerprint typical for the presence of hidden humans has a huge potential to become an extremely powerful technology in this context. Interestingly, until now this approach has received little attention, despite the fact that trained dogs have been used for decades to detect the presence of buried people through scent. In this article we review the current status of using analytical techniques for chemical analysis for search and rescue operations, and discuss the challenges and future directions. As a practical implementation of this idea, we describe a prototype portable device for use in the rapid location of hidden or entrapped people that employs ion mobility spectrometry and a sensor array for the recognition of the chemical signature of the presence of humans.
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Affiliation(s)
- Pawel Mochalski
- Breath Research Institute of the University of Innsbruck, Rathausplatz 4, A-6850 Dornbirn, Austria
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Monitoring of selected skin- and breath-borne volatile organic compounds emitted from the human body using gas chromatography ion mobility spectrometry (GC-IMS). J Chromatogr B Analyt Technol Biomed Life Sci 2018; 1076:29-34. [DOI: 10.1016/j.jchromb.2018.01.013] [Citation(s) in RCA: 47] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/04/2017] [Revised: 12/12/2017] [Accepted: 01/10/2018] [Indexed: 11/24/2022]
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Calibration and validation of a MCC/IMS prototype for exhaled propofol online measurement. J Pharm Biomed Anal 2017; 145:293-297. [DOI: 10.1016/j.jpba.2017.06.052] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2017] [Revised: 06/19/2017] [Accepted: 06/22/2017] [Indexed: 12/16/2022]
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Hüppe T, Lorenz D, Wachowiak M, Maurer F, Meiser A, Groesdonk H, Fink T, Sessler DI, Kreuer S. Volatile organic compounds in ventilated critical care patients: a systematic evaluation of cofactors. BMC Pulm Med 2017; 17:116. [PMID: 28830533 PMCID: PMC5567647 DOI: 10.1186/s12890-017-0460-0] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2016] [Accepted: 08/11/2017] [Indexed: 01/26/2023] Open
Abstract
Background Expired gas (exhalome) analysis of ventilated critical ill patients can be used for drug monitoring and biomarker diagnostics. However, it remains unclear to what extent volatile organic compounds are present in gases from intensive care ventilators, gas cylinders, central hospital gas supplies, and ambient air. We therefore systematically evaluated background volatiles in inspired gas and their influence on the exhalome. Methods We used multi-capillary column ion-mobility spectrometry (MCC-IMS) breath analysis in five mechanically ventilated critical care patients, each over a period of 12 h. We also evaluated volatile organic compounds in inspired gas provided by intensive care ventilators, in compressed air and oxygen from the central gas supply and cylinders, and in the ambient air of an intensive care unit. Volatiles detectable in both inspired and exhaled gas with patient-to-inspired gas ratios < 5 were defined as contaminating compounds. Results A total of 76 unique MCC-IMS signals were detected, with 39 being identified volatile compounds: 73 signals were from the exhalome, 12 were identified in inspired gas from critical care ventilators, and 34 were from ambient air. Five volatile compounds were identified from the central gas supply, four from compressed air, and 17 from compressed oxygen. We observed seven contaminating volatiles with patient-to-inspired gas ratios < 5, thus representing exogenous signals of sufficient magnitude that might potentially be mistaken for exhaled biomarkers. Conclusions Volatile organic compounds can be present in gas from central hospital supplies, compressed gas tanks, and ventilators. Accurate assessment of the exhalome in critical care patients thus requires frequent profiling of inspired gases and appropriate normalisation of the expired signals.
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Affiliation(s)
- Tobias Hüppe
- Department of Anaesthesiology, Intensive Care and Pain Therapy, Centre of Breath Research, Saarland University Medical Centre, Kirrberger Strasse 100, 66421, Homburg (Saar), Germany.
| | - Dominik Lorenz
- Department of Anaesthesiology, Intensive Care and Pain Therapy, Centre of Breath Research, Saarland University Medical Centre, Kirrberger Strasse 100, 66421, Homburg (Saar), Germany
| | - Mario Wachowiak
- Department of Anaesthesiology and Intensive Care, Klinikum Lünen St.-Marien-Hospital, Lünen, Germany
| | - Felix Maurer
- Department of Anaesthesiology, Intensive Care and Pain Therapy, Centre of Breath Research, Saarland University Medical Centre, Kirrberger Strasse 100, 66421, Homburg (Saar), Germany
| | - Andreas Meiser
- Department of Anaesthesiology, Intensive Care and Pain Therapy, Centre of Breath Research, Saarland University Medical Centre, Kirrberger Strasse 100, 66421, Homburg (Saar), Germany
| | - Heinrich Groesdonk
- Department of Anaesthesiology, Intensive Care and Pain Therapy, Centre of Breath Research, Saarland University Medical Centre, Kirrberger Strasse 100, 66421, Homburg (Saar), Germany
| | - Tobias Fink
- Department of Anaesthesiology, Intensive Care and Pain Therapy, Centre of Breath Research, Saarland University Medical Centre, Kirrberger Strasse 100, 66421, Homburg (Saar), Germany
| | - Daniel I Sessler
- Department of Outcomes Research, Anesthesiology Institute, ASCleveland Clinic, Cleveland, OH, USA
| | - Sascha Kreuer
- Department of Anaesthesiology, Intensive Care and Pain Therapy, Centre of Breath Research, Saarland University Medical Centre, Kirrberger Strasse 100, 66421, Homburg (Saar), Germany
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Maurer F, Geiger M, Volk T, Sessler DI, Kreuer S. Validation of liquid and gaseous calibration techniques for quantification of propofol in breath with sorbent tube Thermal Desorption System GC-MS. J Pharm Biomed Anal 2017; 143:116-122. [PMID: 28586723 DOI: 10.1016/j.jpba.2017.05.042] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2017] [Accepted: 05/25/2017] [Indexed: 12/12/2022]
Abstract
Plasma concentrations of intravenous drugs cannot currently be evaluated in real time to guide clinical dosing. However, a system for estimating plasma concentration of the anesthetic propofol from exhaled breath may soon be available. Developing reliable calibration and analytical validation techniques is thus necessary. We therefore compared the established sorbent tube liquid injection technique with a gas injection procedure using a reference gas generator. We then quantified propofol with Tenax sorbent tubes in combination with gas-chromatography coupled mass spectrometry in the breath of 15 patients (101 measurements). Over the clinically relevant concentration range from 10 to 50 ppbv, coefficient of determination was 0.995 for gas calibration; and over the range from 10 to 100ng, coefficient of determination was 0.996 for liquid calibration. A regression comparing gas to liquid calibration had a coefficient of determination of 0.89; slope 1.05±0.01 (standard deviation). The limit of detection was 0.74ng and the lower limit of quantification was 1.12ng for liquid; the limit of detection was 0.90 ppbv and the lower limit of quantification was 1.36 ppbv for gas. Loaded sorbent tubes were stable for at least 14days without significant propofol loss as determined with either method. Measurements from liquid or gas samples were comparably suitable for evaluation of patient breath samples.
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Affiliation(s)
- Felix Maurer
- CBR- Center of Breach Research, Department of Anaesthesiology, Intensive Care and Pain Therapy, Saarland University Medical Center and Saarland University Faculty of Medicine, 66482 Homburg, Saar, Germany; The Center of Breath Research is part of the Outcomes Research, Cleveland, OH, USA.
| | - Martin Geiger
- CBR- Center of Breach Research, Department of Anaesthesiology, Intensive Care and Pain Therapy, Saarland University Medical Center and Saarland University Faculty of Medicine, 66482 Homburg, Saar, Germany; The Center of Breath Research is part of the Outcomes Research, Cleveland, OH, USA
| | - Thomas Volk
- CBR- Center of Breach Research, Department of Anaesthesiology, Intensive Care and Pain Therapy, Saarland University Medical Center and Saarland University Faculty of Medicine, 66482 Homburg, Saar, Germany; The Center of Breath Research is part of the Outcomes Research, Cleveland, OH, USA
| | - Daniel I Sessler
- Department of Outcomes Research, Anesthesiology Institute, Cleveland Clinic, Cleveland, OH, USA; The Center of Breath Research is part of the Outcomes Research, Cleveland, OH, USA
| | - Sascha Kreuer
- CBR- Center of Breach Research, Department of Anaesthesiology, Intensive Care and Pain Therapy, Saarland University Medical Center and Saarland University Faculty of Medicine, 66482 Homburg, Saar, Germany; The Center of Breath Research is part of the Outcomes Research, Cleveland, OH, USA
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Trefz P, Kamysek S, Fuchs P, Sukul P, Schubert JK, Miekisch W. Drug detection in breath: non-invasive assessment of illicit or pharmaceutical drugs. J Breath Res 2017; 11:024001. [DOI: 10.1088/1752-7163/aa61bf] [Citation(s) in RCA: 29] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
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Maurer F, Lorenz DJ, Pielsticker G, Volk T, Sessler DI, Baumbach JI, Kreuer S. Adherence of volatile propofol to various types of plastic tubing. J Breath Res 2017; 11:016009. [PMID: 28049865 DOI: 10.1088/1752-7163/aa567e] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
Abstract
Propofol is an intravenous anesthetic. Currently, it is not possible to routinely measure blood concentration of the drug in real time. However, multi-capillary column ion-mobility spectrometry of exhaled gas can estimate blood propofol concentration. Unfortunately, adhesion of volatile propofol on plastic materials complicates measurements. Therefore, it is necessary to consider the extent to which volatile propofol adheres to various plastics used in sampling tubing. Perfluoralkoxy (PFA), polytetrafluorethylene (PTFE), polyurethane (PUR), silicone, and Tygon tubing were investigated in an experimental setting using a calibration gas generator (HovaCAL). Propofol gas was measured for one hour at 26 °C, 50 °C, and 90 °C tubing temperature. Test tubing segments were then flushed with N2 to quantify desorption. PUR and Tygon sample tubing absorbed all volatile propofol. The silicone tubing reached the maximum propofol concentration after 119 min which was 29 min after propofol gas exposure stopped. The use of PFA or PTFE tubing produced comparable and reasonably accurate propofol measurements. The desaturation time for the PFA was 10 min shorter at 26 °C than for PTFE. PFA tubing thus seems most suitable for measurement of volatile propofol, with PTFE as an alternative.
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Affiliation(s)
- F Maurer
- Center of Breath Research, Department of Anaesthesiology, Intensive Care and Pain Therapy, Saarland University Medical Center and Saarland University Faculty of Medicine, Building 57, D-66421 Homburg, Germany
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Brock B, Kamysek S, Silz J, Trefz P, Schubert JK, Miekisch W. Monitoring of breath VOCs and electrical impedance tomography under pulmonary recruitment in mechanically ventilated patients. J Breath Res 2017; 11:016005. [PMID: 28068288 DOI: 10.1088/1752-7163/aa53b2] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
Analysis of exhaled VOCs can provide information on physiology, metabolic processes, oxidative stress and lung diseases. In critically ill patients, VOC analysis may be used to gain complimentary information beyond global clinical parameters. This seems especially attractive in mechanically ventilated patients frequently suffering from impairment of gas exchange. This study was intended to assess (a) the effects of recruitment maneuvers onto VOC profiles, (b) the correlations between electrical impedance tomography (EIT) data and VOC profiles and (c) the effects of recruitment onto distribution of ventilation. Eleven mechanically ventilated patients were investigated during lung recruitment after cardiac surgery. Continuous breath gas analysis by means of PTR-ToF-MS, EIT and blood gas analyses were performed simultaneously. More than 300 mass traces could be detected and monitored continuously by means of PTR-ToF-MS in every patient. Exhaled VOC concentrations varied with recruitment induced changes in minute ventilation and cardiac output. Ammonia exhalation depended on blood pH. The improvement in dorsal lung ventilation during recruitment ranged from 9% to 110%. Correlations between exhaled concentrations of acetone, isoprene, benzene sevoflurane and improvement in regional ventilation during recruitment were observed. Extent and quality of these correlations depended on physico-chemical properties of the VOCs. Combination of continuous real-time breath analysis and EIT revealed correlations between exhaled VOC concentrations and distribution of ventilation. This setup enabled immediate recognition of physiological and therapeutic effects in ICU patients. In a perspective, VOC analysis could be used for non-invasive control and optimization of ventilation strategies.
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Affiliation(s)
- Beate Brock
- Department of Anaesthesia and Intensive Care Medicine, Rostock University Medical Center, Schillingallee 35, D-18057 Rostock, Germany
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Wang X, Zhou Q, Jiang D, Gong Y, Li E, Li H. Ion mobility spectrometry as a simple and rapid method to measure the plasma propofol concentrations for intravenous anaesthesia monitoring. Sci Rep 2016; 6:37525. [PMID: 27869199 PMCID: PMC5116632 DOI: 10.1038/srep37525] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2016] [Accepted: 10/31/2016] [Indexed: 01/04/2023] Open
Abstract
The plasma propofol concentration is important information for anaesthetists to monitor and adjust the anaesthesia depth for patients during a surgery operation. In this paper, a stand-alone ion mobility spectrometer (IMS) was constructed for the rapid measurement of the plasma propofol concentrations. Without any sample pre-treatment, the plasma samples were dropped on a piece of glass microfiber paper and then introduced into the IMS cell by the thermal desorption directly. Each individual measurement could be accomplished within 1 min. For the plasma propofol concentrations from 1 to 12 μg mL-1, the IMS response was linear with a correlation coefficient R2 of 0.998, while the limit of detection was evaluated to be 0.1 μg mL-1. These measurement results did meet the clinical application requirements. Furthermore, other clinically-often-used drugs, including remifentanil, flurbiprofen and atracurium, were found no significant interference with the qualitative and quantitative analysis of the plasma propofol. The plasma propofol concentrations measured by IMS were correlated well with those measured by the high performance liquid chromatography (HPLC). The results confirmed an excellent agreement between these two methods. Finally, this method was applied to monitor the plasma propofol concentrations for a patient undergoing surgery, demonstrating its capability of anaesthesia monitoring in real clinical environments.
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Affiliation(s)
- Xin Wang
- Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, Liaoning, 116023, People's Republic of China
| | - Qinghua Zhou
- Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, Liaoning, 116023, People's Republic of China
| | - Dandan Jiang
- Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, Liaoning, 116023, People's Republic of China
| | - Yulei Gong
- Department of Anesthesiology, The First Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang, 150001, People's Republic of China
| | - Enyou Li
- Department of Anesthesiology, The First Affiliated Hospital of Harbin Medical University, Harbin, Heilongjiang, 150001, People's Republic of China
| | - Haiyang Li
- Key Laboratory of Separation Science for Analytical Chemistry, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, Liaoning, 116023, People's Republic of China
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Fernández Del Río R, O'Hara ME, Pemberton P, Whitehouse T, Mayhew CA. Elimination characteristics of post-operative isoflurane levels in alveolar exhaled breath via PTR-MS analysis. J Breath Res 2016; 10:046006. [PMID: 27732571 PMCID: PMC6050519 DOI: 10.1088/1752-7155/10/4/046006] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Isoflurane (1-chloro-2,2,2-trifluoroethyl difluoromethyl ether), C3H2ClF5O, is a commonly used inhalation anaesthetic. Using a proton transfer reaction mass spectrometer (PTR-MS) we have detected isoflurane in the breath of patients several weeks following major surgery. That isoflurane is detected in the breath of patients so long after being anaesthetised raises questions about when cognitive function has fully returned to a patient. Temporal profiles of isoflurane concentrations in breath are presented for five patients (F/M 3/2, mean age 50 years, min-max 36-58 years) who had undergone liver transplant surgery. In addition, results from a headspace analysis of isoflurane are presented so that the product ions resulting from the reactions of H3O+ with isoflurane in PTR-MS could be easily identified in the absence of the complex chemical environment of breath. Six product ions were identified. In order of increasing m/z (using the 35Cl isotope where appropriate) these are [Formula: see text] (m/z 51), CHFCl+ (m/z 67), CF3CHCl+ (m/z 117), C3F4OCl+ (m/z 163), C3H2F4OCl+ (m/z 165), and C3F4OCl+ H2O (m/z 183). No protonated parent was detected. For the headspace study both clean air and CO2 enriched clean air (4% CO2) were used as buffer gases in the drift tube of the PTR-MS. The CO2 enriched air was used to determine if exhaled breath would affect the product ion branching ratios. Importantly no significant differences were observed, and therefore for isoflurane the product ion distributions determined in a normal air mixture can be used for breath analysis. Given that PTR-MS can be operated under different reduced electric fields (E/N), the dependence of the product ion branching percentages for isoflurane on E/N (96-138 Td) are reported.
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Affiliation(s)
- R Fernández Del Río
- Molecular Physics Group, School of Physics and Astronomy, University of Birmingham, Birmingham B15 2TT, UK
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Sen Majumder S, Bhadra A. When Love Is in the Air: Understanding Why Dogs Tend to Mate when It Rains. PLoS One 2015; 10:e0143501. [PMID: 26629906 PMCID: PMC4668084 DOI: 10.1371/journal.pone.0143501] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2015] [Accepted: 11/05/2015] [Indexed: 12/02/2022] Open
Abstract
Seasonality of reproduction is observed in many species of organisms, across taxa, and is influenced by both biotic and abiotic factors. While such seasonality is easy to understand in temperate species exposed to extreme climates, it is more difficult to explain in the tropics. In many tropical species offspring are born during the season of high precipitation, which also coincides with high resource availability. Interestingly, in India, free-ranging dogs seem to mate, and not whelp, when it rains—an observation that cannot be explained by the resource abundance hypothesis. We carried out an extensive study to identify the mating seasons of free-ranging dogs, and observed a strong correlation between both the incidence and frequency of mating related behaviours of dogs, and precipitation levels. There are two clear mating seasons, of which the primary mating season coincides with the monsoon (rainy season) and the secondary mating season coincides with the nor’westerlies in this part of India. We speculate that this strong correlation is an effect of chemistry, rather than biology. While male dogs can mate round the year, females come into estrous seasonally. In the urban environment, dogs are exposed to a lot of olfactory noise, which can dilute the signal present in sex pheromones of the females in heat. A shower leads to increased humidity and reduced temperature of the air, leading to intensification of pheromone signals that trigger a sexual response in the dogs.
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Affiliation(s)
- Sreejani Sen Majumder
- Behaviour and Ecology Lab, Department of Biological Sciences, Indian Institute of Science Education and Research–Kolkata, Kolkata, India
| | - Anindita Bhadra
- Behaviour and Ecology Lab, Department of Biological Sciences, Indian Institute of Science Education and Research–Kolkata, Kolkata, India
- * E-mail:
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Abstract
Propofol is an intravenous agent used commonly for the induction and maintenance of anesthesia, procedural, and critical care sedation in children. The mechanisms of action on the central nervous system involve interactions at various neurotransmitter receptors, especially the gamma-aminobutyric acid A receptor. Approved for use in the USA by the Food and Drug Administration in 1989, its use for induction of anesthesia in children less than 3 years of age still remains off-label. Despite its wide use in pediatric anesthesia, there is conflicting literature about its safety and serious adverse effects in particular subsets of children. Particularly as children are not "little adults", in this review, we emphasize the maturational aspects of propofol pharmacokinetics. Despite the myriad of propofol pharmacokinetic-pharmacodynamic studies and the ability to use allometrical scaling to smooth out differences due to size and age, there is no optimal model that can be used in target controlled infusion pumps for providing closed loop total intravenous anesthesia in children. As the commercial formulation of propofol is a nutrient-rich emulsion, the risk for bacterial contamination exists despite the Food and Drug Administration mandating addition of antimicrobial preservative, calling for manufacturers' directions to discard open vials after 6 h. While propofol has advantages over inhalation anesthesia such as less postoperative nausea and emergence delirium in children, pain on injection remains a problem even with newer formulations. Propofol is known to depress mitochondrial function by its action as an uncoupling agent in oxidative phosphorylation. This has implications for children with mitochondrial diseases and the occurrence of propofol-related infusion syndrome, a rare but seriously life-threatening complication of propofol. At the time of this review, there is no direct evidence in humans for propofol-induced neurotoxicity to the infant brain; however, current concerns of neuroapoptosis in developing brains induced by propofol persist and continue to be a focus of research.
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Affiliation(s)
- Vidya Chidambaran
- Department of Anesthesia, Cincinnati Children's Hospital Medical Center, 3333 Burnet Avenue, MLC 2001, Cincinnati, OH, 45229, USA,
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Kunze N, Weigel C, Vautz W, Schwerdtfeger K, Jünger M, Quintel M, Perl T. Multi-capillary column-ion mobility spectrometry (MCC-IMS) as a new method for the quantification of occupational exposure to sevoflurane in anaesthesia workplaces: an observational feasibility study. J Occup Med Toxicol 2015; 10:12. [PMID: 25829942 PMCID: PMC4379543 DOI: 10.1186/s12995-015-0056-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2014] [Accepted: 03/17/2015] [Indexed: 11/29/2022] Open
Abstract
Background Occupational exposure to sevoflurane has the potential to cause health damage in hospital personnel. Workplace contamination with the substance mostly is assessed by using photoacoustic infrared spectrometry with detection limits of 10 ppbv. Multi-capillary column-ion mobility spectrometry (MCC-IMS) could be an alternative technology for the quantification of sevoflurane in the room air and could be even more accurate because of potentially lower detection limits. The aim of this study was to test the hypothesis that MCC-IMS is able to detect and monitor very low concentrations of sevoflurane (<10 ppbv) and to evaluate the exposure of hospital personnel to sevoflurane during paediatric anaesthesia and in the post anaesthesia care unit (PACU). Methods A MCC-IMS device was calibrated to several concentrations of sevoflurane and limits of detection (LOD) and quantification (LOQ) were calculated. Sevoflurane exposure of hospital personnel was measured at two anaesthesia workplaces and time-weighted average (TWA) values were calculated. Results The LOD was 0.0068 ppbv and the LOQ was 0.0189 ppbv. During paediatric anaesthesia the mean sevoflurane concentration was 46.9 ppbv (8.0 - 314.7 ppbv) with TWA values between 5.8 and 45.7 ppbv. In the PACU the mean sevoflurane concentration was 27.9 ppbv (8.0 – 170.2 ppbv) and TWA values reached from 8.3 to 45.1 ppbv. Conclusions MCC-IMS shows a significantly lower LOD and LOQ than comparable methods. It is a reliable technology for monitoring sevoflurane concentrations at anaesthesia workplaces and has a particular strength in quantifying low-level contaminations of sevoflurane. The exposure of the personnel working in these areas did not exceed recommended limits and therefore adverse health effects are unlikely.
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Affiliation(s)
- Nils Kunze
- Department for Anaesthesiology, Centre for Anaesthesiology, Emergency and Intensive Care Medicine, University Medical Centre, University of Göttingen, Robert-Koch-Straße 40, 37075 Göttingen, Germany
| | - Cathrin Weigel
- Department for Anaesthesiology, Centre for Anaesthesiology, Emergency and Intensive Care Medicine, University Medical Centre, University of Göttingen, Robert-Koch-Straße 40, 37075 Göttingen, Germany
| | - Wolfgang Vautz
- Leibniz-Insitut für Analytische Wissenschaften - ISAS - e. V, Bunsen-Kirchhoff-Straße 11, 44139 Dortmund, Germany
| | - Katrin Schwerdtfeger
- Department for Anaesthesiology, Centre for Anaesthesiology, Emergency and Intensive Care Medicine, University Medical Centre, University of Göttingen, Robert-Koch-Straße 40, 37075 Göttingen, Germany
| | - Melanie Jünger
- Department of Molecular Plant Genetics, University of Hamburg, Ohnhorststraße 18, 22609 Hamburg, Germany
| | - Michael Quintel
- Department for Anaesthesiology, Centre for Anaesthesiology, Emergency and Intensive Care Medicine, University Medical Centre, University of Göttingen, Robert-Koch-Straße 40, 37075 Göttingen, Germany
| | - Thorsten Perl
- Department for Anaesthesiology, Centre for Anaesthesiology, Emergency and Intensive Care Medicine, University Medical Centre, University of Göttingen, Robert-Koch-Straße 40, 37075 Göttingen, Germany
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Cumeras R, Figueras E, Davis CE, Baumbach JI, Gràcia I. Review on ion mobility spectrometry. Part 1: current instrumentation. Analyst 2015; 140:1376-90. [PMID: 25465076 PMCID: PMC4331213 DOI: 10.1039/c4an01100g] [Citation(s) in RCA: 268] [Impact Index Per Article: 29.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Ion Mobility Spectrometry (IMS) is a widely used and 'well-known' technique of ion separation in the gaseous phase based on the differences in ion mobilities under an electric field. All IMS instruments operate with an electric field that provides space separation, but some IMS instruments also operate with a drift gas flow that provides also a temporal separation. In this review we will summarize the current IMS instrumentation. IMS techniques have received an increased interest as new instrumentation and have become available to be coupled with mass spectrometry (MS). For each of the eight types of IMS instruments reviewed it is mentioned whether they can be hyphenated with MS and whether they are commercially available. Finally, out of the described devices, the six most-consolidated ones are compared. The current review article is followed by a companion review article which details the IMS hyphenated techniques (mainly gas chromatography and mass spectrometry) and the factors that make the data from an IMS device change as a function of device parameters and sampling conditions. These reviews will provide the reader with an insightful view of the main characteristics and aspects of the IMS technique.
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Affiliation(s)
- R Cumeras
- Institut de Microelectrònica de Barcelona, IMB-CNM (CSIC), Esfera UAB, Campus UAB s/n, E-08193 Bellaterra, Barcelona, Spain.
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LIU Y, GONG Y, WANG C, WANG X, ZHOU Q, WANG D, GUO L, PI X, ZHANG X, LUO S, LI H, LI E. Online breath analysis of propofol during anesthesia: clinical application of membrane inlet-ion mobility spectrometry. Acta Anaesthesiol Scand 2015; 59:319-28. [PMID: 25565144 DOI: 10.1111/aas.12448] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2014] [Accepted: 11/17/2014] [Indexed: 12/20/2022]
Abstract
BACKGROUND Breath analysis of propofol is a potential noninvasive method for approximating the plasma propofol concentration. There have been various reported techniques for measuring the exhaled propofol concentration at steady state; however, the propofol concentration undergoes marked changes during clinical anesthesia. Therefore, this study investigated the use of membrane inlet-ion mobility spectrometry (MI-IMS) to monitor exhaled propofol discontinuously and continuously during propofol anesthesia. METHODS The study included 19 patients of American Society of Anesthesiologists physical status I or II. In experiment I (discontinuous study), breath and blood samples were collected discontinuously, with stable target propofol concentrations of 2.8 μg/ml, 3.2 μg/ml, 3.5 μg/ml, and 3.8 μg/ml. In experiment II (continuous study), propofol concentration was maintained at 3.5 μg/ml after induction, and exhaled breath was collected continuously every 3 min during propofol infusion. Relationships of the exhaled propofol concentration with the plasma propofol concentration, measured by high-performance liquid chromatography and the continuously measured bispectral (BIS) index were investigated. RESULTS Comparison of the exhaled and plasma propofol concentrations revealed a bias ± precision of 2.1% ± 14.6% (95% limits of agreement: - 26.5-30.7%) in experiment I and - 10.4% ± 13.2 (- 36.3-15.4%) in experiment II. In both experiments, exhaled propofol concentrations measured by MI-IMS were consistent with, the propofol effect represented by the BIS index. CONCLUSIONS MI-IMS may be a suitable method to predict plasma propofol concentration online during propofol anesthesia. Monitoring exhaled propofol may improve the safety of propofol anesthesia.
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Affiliation(s)
- Y. LIU
- Department of Anesthesiology; The First Affiliated Hospital of Harbin Medical University; Harbin Heilongjiang China
| | - Y. GONG
- Department of Anesthesiology; The First Affiliated Hospital of Harbin Medical University; Harbin Heilongjiang China
| | - C. WANG
- Department of Anesthesiology; The First Affiliated Hospital of Harbin Medical University; Harbin Heilongjiang China
| | - X. WANG
- Dalian Institute of Chemical Physics; Chinese Academy of Sciences; Dalian Liaoning China
| | - Q. ZHOU
- Dalian Institute of Chemical Physics; Chinese Academy of Sciences; Dalian Liaoning China
| | - D. WANG
- Department of Anesthesiology; The First Affiliated Hospital of Harbin Medical University; Harbin Heilongjiang China
| | - L. GUO
- Department of Anesthesiology; The First Affiliated Hospital of Harbin Medical University; Harbin Heilongjiang China
| | - X. PI
- Department of Anesthesiology; The First Affiliated Hospital of Harbin Medical University; Harbin Heilongjiang China
| | - X. ZHANG
- Department of Anesthesiology; The First Affiliated Hospital of Harbin Medical University; Harbin Heilongjiang China
| | - S. LUO
- Department of Anesthesiology; The First Affiliated Hospital of Harbin Medical University; Harbin Heilongjiang China
| | - H. LI
- Dalian Institute of Chemical Physics; Chinese Academy of Sciences; Dalian Liaoning China
| | - E. LI
- Department of Anesthesiology; The First Affiliated Hospital of Harbin Medical University; Harbin Heilongjiang China
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Zhou Q, Li E, Wang Z, Gong Y, Wang C, Guo L, Li H. Time-resolved dynamic dilution introduction for ion mobility spectrometry and its application in end-tidal propofol monitoring. J Breath Res 2015; 9:016002. [DOI: 10.1088/1752-7155/9/1/016002] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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