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Mallat J, Lemyze M, Fischer MO. Passive leg raising test induced changes in plethysmographic variability index to assess fluid responsiveness in critically ill mechanically ventilated patients with acute circulatory failure. J Crit Care 2024; 79:154449. [PMID: 37857068 DOI: 10.1016/j.jcrc.2023.154449] [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: 05/09/2023] [Revised: 08/20/2023] [Accepted: 10/12/2023] [Indexed: 10/21/2023]
Abstract
BACKGROUND Passive leg raising (PLR) reliably predicts fluid responsiveness but requires a real-time cardiac index (CI) measurement or the presence of an invasive arterial line to achieve this effect. The plethysmographic variability index (PVI), an automatic measurement of the respiratory variation of the perfusion index, is non-invasive and continuously displayed on the pulse oximeter device. We tested whether PLR-induced changes in PVI (ΔPVIPLR) could accurately predict fluid responsiveness in mechanically ventilated patients with acute circulatory failure. METHODS This was a secondary analysis of an observational prospective study. We included 29 mechanically ventilated patients with acute circulatory failure in this study. We measured PVI (Radical-7 device; Masimo Corp., Irvine, CA) and CI (Echocardiography) before and during a PLR test and before and after volume expansion of 500 mL of crystalloid solution. A volume expansion-induced increase in CI of >15% defined fluid responsiveness. To investigate whether ΔPVIPLR can predict fluid responsiveness, we determined areas under the receiver operating characteristic curves (AUROCs) and gray zones for ΔPVIPLR. RESULTS Of the 29 patients, 27 (93.1%) received norepinephrine. The median tidal volume was 7.0 [IQR: 6.6-7.6] mL/kg ideal body weight. Nineteen patients (65.5%) were classified as fluid responders (increase in CI > 15% after volume expansion). Relative ΔPVIPLR accurately predicted fluid responsiveness with an AUROC of 0.89 (95%CI: 0.72-0.98, p < 0.001). A decrease in PVI ≤ -24.1% induced by PLR detected fluid responsiveness with a sensitivity of 95% (95%CI: 74-100%) and a specificity of 80% (95%CI: 44-97%). Gray zone was acceptable, including 13.8% of patients. The correlations between the relative ΔPVIPLR and changes in CI induced by PLR and by volume expansion were significant (r = -0.58, p < 0.001, and r = -0.65, p < 0.001; respectively). CONCLUSIONS In sedated and mechanically ventilated ICU patients with acute circulatory failure, PLR-induced changes in PVI accurately predict fluid responsiveness with an acceptable gray zone. TRIAL REGISTRATION ClinicalTrials.govNCT03225378.
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Affiliation(s)
- Jihad Mallat
- Department of Critical Care Medicine, Arras Hospital, 6200 Arras, France; Critical Care Institute, Cleveland Clinic Abu Dhabi, Abu Dhabi, United Arab Emirates; Cleveland Clinic Lerner College of Medicine of Case Western Reserve University, Cleveland, OH, USA; Normandy University, UNICAEN, ED 497, Caen, France.
| | - Malcolm Lemyze
- Department of Critical Care Medicine, Arras Hospital, 6200 Arras, France
| | - Marc-Olivier Fischer
- Institut Aquitain du Cœur, Clinique Saint Augustin, ELSAN, 114 Avenue d'Arès, 33 074 Bordeaux Cedex, France
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2
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Tetzner F, Schlüter-Albrecht S, Rackwitz L, Clarius M, Nöth U, Reyle-Hahn SM. [Pain therapy and anaesthesiological procedures in fast-track arthroplasty]. DER ORTHOPADE 2022; 51:358-365. [PMID: 35412088 DOI: 10.1007/s00132-022-04248-3] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 03/14/2022] [Indexed: 12/19/2022]
Abstract
Since the introduction of fast-track surgery in the field of arthroplasty, all disciplines involved have been challenged with the task of close and continuous joint communication in the context of daily routine care. Processes that have been agreed upon interdisciplinarily must be reviewed at regular intervals, and, if necessary, adapted and newly agreed upon with the aim of optimizing the perioperative risks both medically and along the therapeutic pathway. The responsibility of the anaesthesiologist is not only limited to the performance of anaesthesia, but also includes the care of patients with a view to optimal pain therapy, maintenance of homeostasis and ensuring a rapid return of the patient's self-determination.
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Affiliation(s)
- Fabian Tetzner
- Klinik für Anästhesiologie und Interdisziplinäre Intensivmedizin, Evangelisches Waldkrankenhaus Spandau, Stadtrandstraße 555, 13589, Berlin, Deutschland
| | - Sabine Schlüter-Albrecht
- Klinik für Anästhesiologie und Interdisziplinäre Intensivmedizin, Evangelisches Waldkrankenhaus Spandau, Stadtrandstraße 555, 13589, Berlin, Deutschland
| | - Lars Rackwitz
- Klinik für Orthopädie und Unfallchirurgie, Evangelisches Waldkrankenhaus Spandau, Berlin, Deutschland
| | - Michael Clarius
- Klinik für Orthopädie, Orthopädische Chirurgie und Unfallchirurgie, Vulpius Klinik, Bad Rappenau, Deutschland
| | - Ulrich Nöth
- Klinik für Orthopädie und Unfallchirurgie, Evangelisches Waldkrankenhaus Spandau, Berlin, Deutschland
| | - Stephan-Matthias Reyle-Hahn
- Klinik für Anästhesiologie und Interdisziplinäre Intensivmedizin, Evangelisches Waldkrankenhaus Spandau, Stadtrandstraße 555, 13589, Berlin, Deutschland.
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3
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García-de-Acilu M, Pacheco A, Santafé M, Ramos FJ, Ruiz-Rodríguez JC, Ferrer R, Roca O. Pleth variability index may predict preload responsiveness in patients treated with nasal high flow: a physiological study. J Appl Physiol (1985) 2021; 130:1660-1667. [PMID: 33856256 DOI: 10.1152/japplphysiol.00614.2020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
The purpose of this study was to determine whether the plethysmographic variability index ("PVi") can predict preload responsiveness in patients with nasal high flow (NHF) (≥30 L/min) with any sign of hypoperfusion. "Preload responsiveness" was defined as a ≥10% increase in stroke volume (SV), measured by transthoracic echocardiography, after passive leg raising. SV and PVi were reassessed in preload responders after receiving a 250-mL fluid challenge. Twenty patients were included and 12 patients (60%) were preload responders. Responders showed higher baseline mean PVi (24% vs. 13%; P = 0.001) and higher mean PVi variation (ΔPVi) after passive leg raising (6.8% vs. -1.7%; P < 0.001). No differences between mean ΔPVi after passive leg raising and mean ΔPVi after fluid challenge were observed (6.8% vs. 7.4%; P = 0.24); and both values were strongly correlated (r = 0.84; P < 0.001). Baseline PVi and ΔPVi after passive leg raising showed excellent diagnostic accuracy identifying preload responders (AUROC 0.92 and 1.00, respectively). Baseline PVi ≥ 16% had a sensitivity of 91.7% and a specificity of 87.5% for detecting preload responders. Similarly, ΔPVi after passive leg raising ≥2% had a 100% of both sensitivity and specificity. Thus, PVi might predict "preload responsiveness" in patients treated with NHF, suggesting that it may guide fluid administration in these patients.NEW & NOTEWORTHY This is the first study that analyzes the use of noninvasive plethysmographic variability index (PVi) for preload assessment in patients treated with nasal high flow (NHF). Its results showed that PVi might identify preload responders. Therefore, PVi may be used in the day-to-day clinical decision-making process in critically ill patients treated with NHF, helping to provide adequate resuscitation volume.
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Affiliation(s)
- Marina García-de-Acilu
- Servei de Medicina Intensiva, Hospital Universitari Vall d'Hebron, Institut de Recerca Vall d'Hebron, Barcelona, Spain.,Departament de Medicina, Universitat Autònoma de Barcelona, Bellaterra, Spain
| | - Andrés Pacheco
- Servei de Medicina Intensiva, Hospital Universitari Vall d'Hebron, Institut de Recerca Vall d'Hebron, Barcelona, Spain
| | - Manel Santafé
- Servei de Medicina Intensiva, Hospital Universitari Vall d'Hebron, Institut de Recerca Vall d'Hebron, Barcelona, Spain
| | - Francisco-Javier Ramos
- Servei de Medicina Intensiva, Hospital Universitari Vall d'Hebron, Institut de Recerca Vall d'Hebron, Barcelona, Spain
| | - Juan C Ruiz-Rodríguez
- Servei de Medicina Intensiva, Hospital Universitari Vall d'Hebron, Institut de Recerca Vall d'Hebron, Barcelona, Spain
| | - Ricard Ferrer
- Servei de Medicina Intensiva, Hospital Universitari Vall d'Hebron, Institut de Recerca Vall d'Hebron, Barcelona, Spain.,Ciber Enfermedades Respiratorias, Instituto de Salud Carlos III, Madrid, Spain
| | - Oriol Roca
- Servei de Medicina Intensiva, Hospital Universitari Vall d'Hebron, Institut de Recerca Vall d'Hebron, Barcelona, Spain.,Ciber Enfermedades Respiratorias, Instituto de Salud Carlos III, Madrid, Spain
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Abstract
Anesthesiologists are uniquely positioned to facilitate emergent care of patients with sepsis in the perioperative setting. A subset of sepsis patients presents with surgical pathology. Emphasis is on timely intervention with source control, antibiotic therapy, and aggressive resuscitation. Ileus, aspiration, and cardiovascular collapse must be considered when inducing patients with sepsis. Dynamic fluid responsiveness may prove an effective tool in minimizing over-resuscitation. Assessment of circulatory failure and drug therapy involves an understanding of preload, afterload, and contractility. Timely, targeted resuscitation and early source control have persisted and remain fundamental to sepsis care.
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Affiliation(s)
- Arpit Patel
- Department of Anesthesiology, Perioperative Care and Pain Medicine, NYU Langone Health, NYU Langone Medical Center, 550 1st Avenue, New York, NY 10016, USA
| | - Mark E Nunnally
- Department of Anesthesiology, Perioperative Care and Pain Medicine, NYU Langone Health, NYU Langone Medical Center, 550 1st Avenue, New York, NY 10016, USA.
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5
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Schaefer MS, Serpa Neto A, Pelosi P, Gama de Abreu M, Kienbaum P, Schultz MJ, Meyer-Treschan TA. Temporal Changes in Ventilator Settings in Patients With Uninjured Lungs: A Systematic Review. Anesth Analg 2020; 129:129-140. [PMID: 30222649 DOI: 10.1213/ane.0000000000003758] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
In patients with uninjured lungs, increasing evidence indicates that tidal volume (VT) reduction improves outcomes in the intensive care unit (ICU) and in the operating room (OR). However, the degree to which this evidence has translated to clinical changes in ventilator settings for patients with uninjured lungs is unknown. To clarify whether ventilator settings have changed, we searched MEDLINE, Cochrane Central Register of Controlled Trials, and Web of Science for publications on invasive ventilation in ICUs or ORs, excluding those on patients <18 years of age or those with >25% of patients with acute respiratory distress syndrome (ARDS). Our primary end point was temporal change in VT over time. Secondary end points were changes in maximum airway pressure, mean airway pressure, positive end-expiratory pressure, inspiratory oxygen fraction, development of ARDS (ICU studies only), and postoperative pulmonary complications (OR studies only) determined using correlation analysis and linear regression. We identified 96 ICU and 96 OR studies comprising 130,316 patients from 1975 to 2014 and observed that in the ICU, VT size decreased annually by 0.16 mL/kg (-0.19 to -0.12 mL/kg) (P < .001), while positive end-expiratory pressure increased by an average of 0.1 mbar/y (0.02-0.17 mbar/y) (P = .017). In the OR, VT size decreased by 0.09 mL/kg per year (-0.14 to -0.04 mL/kg per year) (P < .001). The change in VTs leveled off in 1995. Other intraoperative ventilator settings did not change in the study period. Incidences of ARDS (ICU studies) and postoperative pulmonary complications (OR studies) also did not change over time. We found that, during a 39-year period, from 1975 to 2014, VTs in clinical studies on mechanical ventilation have decreased significantly in the ICU and in the OR.
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Affiliation(s)
- Maximilian S Schaefer
- From the Department of Anesthesiology, Düsseldorf University Hospital, Düsseldorf, Germany
| | - Ary Serpa Neto
- Department of Critical Care Medicine, Hospital Israelita Albert Einstein, São Paulo, Brazil.,Program of Post-Graduation, Innovation and Research, Faculdade de Medicina do ABC, Santo Andre, Brazil
| | - Paolo Pelosi
- Department of Surgical Sciences and Integrated Diagnostics, San Martino Policlinico Hospital, Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) for Oncology, Genoa, Italy
| | - Marcelo Gama de Abreu
- Department of Anesthesiology and Intensive Care Therapy, Pulmonary Engineering Group, University Hospital Carl Gustav Carus, Dresden, Germany
| | - Peter Kienbaum
- From the Department of Anesthesiology, Düsseldorf University Hospital, Düsseldorf, Germany
| | - Marcus J Schultz
- Department of Intensive Care, Academic Medical Center, University of Amsterdam, the Netherlands
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6
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Bennett VA, Aya HD, Cecconi M. Evaluation of cardiac function using heart-lung interactions. ANNALS OF TRANSLATIONAL MEDICINE 2018; 6:356. [PMID: 30370283 DOI: 10.21037/atm.2018.08.10] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Heart lung interactions can be used clinically to assist in the evaluation of cardiac function. Application of these interactions and understanding of the physiology underlying them has formed a focus of research over a number of years. The changes in preload induced by changes in intrathoracic pressure (ITP) with the respiratory cycle, have been applied to form dynamic tests of fluid responsiveness. Pulse pressure variation (PPV), stroke volume variation (SVV), end expiratory occlusion test, pleth variability index (PVI) and use of echocardiography are all clinical assessments that can be made at the bedside. However, there are limitations and pitfalls to each that restrict their use to specific situations. The haemodynamic response to treatment with continuous positive airway pressure (CPAP) in left ventricular failure is explained by the presence of heart lung interactions, and works predominately through afterload reduction. Similarly, in other disease states such as acute respiratory distress syndrome (ARDS), the effects of a change in ventilation can provide information about both the cardiac and respiratory system. This review aims to summarise how assessment of cardiac function using heart lung interactions can be performed. It introduces the underlying physiology and some of the clinical applications that are further explored in other articles within the series.
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Affiliation(s)
- Victoria A Bennett
- Department of Intensive Care Medicine, St George's University Hospital NHS Foundation Trust, Blackshaw Road, London, UK
| | - Hollmann D Aya
- Department of Intensive Care Medicine, St George's University Hospital NHS Foundation Trust, Blackshaw Road, London, UK
| | - Maurizio Cecconi
- Humanitas Clinical and Research Center, Rozzano, Milan, Italy.,Department of Biomedical Sciences, Humanitas University, Pieve Emanuele, Milan, Italy
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7
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Lee JH, Yang S, Park J, Kim HC, Kim EH, Jang YE, Kim JT, Kim HS. Time to consider the contact force during photoplethysmography measurement during pediatric anesthesia: A prospective, nonrandomized interventional study. Paediatr Anaesth 2018; 28:660-667. [PMID: 29920853 DOI: 10.1111/pan.13415] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Accepted: 04/30/2018] [Indexed: 12/15/2022]
Abstract
BACKGROUND Respiratory variations in photoplethysmography amplitude enable volume status assessment. However, the contact force between the measurement site and sensor can affect photoplethysmography waveforms. We aimed to evaluate contact force effects on respiratory variations in photoplethysmography waveforms in children under general anesthesia. METHODS Children aged 3-5 years were enrolled. After anesthetic induction, mechanical ventilation commenced at a tidal volume of 10 mL/kg. Photoplethysmographic signals were obtained in the supine position from the index finger using a force sensor-integrated clip-type photoplethysmography sensor that increased the contact force from 0-1.4 N for 20 respiratory cycles at each force. The AC amplitude (pulsatile component), DC amplitude (nonpulsatile component), AC/DC ratio, and respiratory variations in photoplethysmography amplitude were calculated. RESULTS Data from 34 children were analyzed. Seven contact forces at 0.2-N increments were evaluated for each patient. The normalized AC amplitude increased maximally at a contact force of 0.4-0.6 N and decreased with increasing contact force. However, the normalized DC amplitude increased with a contact force exceeding 0.4 N. ΔPOP decreased slightly and increased from the point when the AC amplitude started to decrease as contact force increased. In a 0.2-1.2 N contact force range, significant changes in the normalized AC amplitude, normalized DC amplitude, AC/DC ratio, and respiratory variations in photoplethysmography amplitude were observed. CONCLUSION Respiratory variations in photoplethysmography amplitude changed according to variable contact forces; therefore, these measurements may not reflect respiration-induced stroke volume variations. Clinicians should consider contact force bias when interpreting morphological data from photoplethysmography signals.
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Affiliation(s)
- Ji-Hyun Lee
- Department of Anaesthesiology and Pain Medicine, Seoul National University College of Medicine, Seoul National University Hospital, Seoul, Korea
| | - Seungman Yang
- Interdisciplinary Program for Bioengineering, Seoul National University Graduate School, Seoul, Korea
| | - Jonghyun Park
- Interdisciplinary Program for Bioengineering, Seoul National University Graduate School, Seoul, Korea
| | - Hee Chan Kim
- Interdisciplinary Program for Bioengineering, Seoul National University Graduate School, Seoul, Korea.,Department of Biomedical Engineering, Seoul National University College of Medicine, Seoul, Korea
| | - Eun-Hee Kim
- Department of Anaesthesiology and Pain Medicine, Seoul National University College of Medicine, Seoul National University Hospital, Seoul, Korea
| | - Young-Eun Jang
- Department of Anaesthesiology and Pain Medicine, Seoul National University College of Medicine, Seoul National University Hospital, Seoul, Korea
| | - Jin-Tae Kim
- Department of Anaesthesiology and Pain Medicine, Seoul National University College of Medicine, Seoul National University Hospital, Seoul, Korea
| | - Hee-Soo Kim
- Department of Anaesthesiology and Pain Medicine, Seoul National University College of Medicine, Seoul National University Hospital, Seoul, Korea
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8
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Yamada T, Vacas S, Gricourt Y, Cannesson M. Improving Perioperative Outcomes Through Minimally Invasive and Non-invasive Hemodynamic Monitoring Techniques. Front Med (Lausanne) 2018; 5:144. [PMID: 29868596 PMCID: PMC5966660 DOI: 10.3389/fmed.2018.00144] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2018] [Accepted: 04/25/2018] [Indexed: 01/10/2023] Open
Abstract
An increasing number of patients require precise intraoperative hemodynamic monitoring due to aging and comorbidities. To prevent undesirable outcomes from intraoperative hypotension or hypoperfusion, appropriate threshold settings are required. These setting can vary widely from patient to patient. Goal-directed therapy techniques allow for flow monitoring as the standard for perioperative fluid management. Based on the concept of personalized medicine, individual assessment and treatment are more advantageous than conventional or uniform interventions. The recent development of minimally and noninvasive monitoring devices make it possible to apply detailed control, tracking, and observation of broad patient populations, all while reducing adverse complications. In this manuscript, we review the monitoring features of each device, together with possible advantages and disadvantages of their use in optimizing patient hemodynamic management.
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Affiliation(s)
- Takashige Yamada
- Department of Anesthesiology and Perioperative Medicine, University of California, Los Angeles, Los Angeles, CA, United States.,Department of Anesthesiology, Keio University School of Medicine, Tokyo, Japan
| | - Susana Vacas
- Department of Anesthesiology and Perioperative Medicine, University of California, Los Angeles, Los Angeles, CA, United States
| | - Yann Gricourt
- Departement Anesthesie Réanimation Douleur Urgence, Centre Hospitalaire Universitaire Caremeau, Nimes, France
| | - Maxime Cannesson
- Department of Anesthesiology and Perioperative Medicine, University of California, Los Angeles, Los Angeles, CA, United States
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9
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Le Guen M, Follin A, Gayat E, Fischler M. The plethysmographic variability index does not predict fluid responsiveness estimated by esophageal Doppler during kidney transplantation: A controlled study. Medicine (Baltimore) 2018; 97:e10723. [PMID: 29768341 PMCID: PMC5976303 DOI: 10.1097/md.0000000000010723] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 12/30/2022] Open
Abstract
Research is ongoing to find a noninvasive method of monitoring, which can predict fluid responsiveness in patients undergoing kidney transplantation.To compare the responses to fluid challenges with the Pleth Variability Index, a noninvasive dynamic index derived from plethysmographic variability (Radical 7 pulse oximeter; Masimo Corporation, Irvine, CA), and the esophageal Doppler, the criterion standard.Observational study.University hospital; study from May 2011 and May 2012.Forty-eight patients with end-renal function were included and 44 analyzed. Patients with cardiac failure were not eligible.Fluid challenges were administered during maintenance of general anesthesia but before skin incision and repeated if the patient was deemed to be a "responder" (increase in stroke volume ≥10%).The primary endpoint was to assess if the Pleth Variability Index is an accurate predictor of fluid responsiveness.Among 76 fluid challenges, 38 were considered as positive (increase in stroke volume measured by Doppler ≥10%). Pleth Variability Index was similar at baseline between responders and nonresponder patients. Fluid challenges were associated with a significant decrease in Pleth Variability Index in overall cases (12 [8-14] vs 10 [6-17], P = .050), but it was not able to discriminate between responders (12 [8-15] vs 10 [5-15], P = .650) and nonresponders (11 [6-16] vs 8 [5-14], P = .047). The area under the Receiver Operating Characteristic curve for Pleth Variability Index was 0.49 (0.36-0.62).Pleth Variability Index is not an accurate predictor of fluid responsiveness during kidney transplantation.
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Affiliation(s)
- Morgan Le Guen
- Department of Anesthesiology, Hôpital Foch
- Université Versailles Saint-Quentin en Yvelines, Suresnes
| | - Arnaud Follin
- Department of Anesthesiology, Hôpital Foch
- Université Versailles Saint-Quentin en Yvelines, Suresnes
| | - Etienne Gayat
- Department of Anesthesiology and Critical Care Medicine, Hôpital Saint Louis-Lariboisière-Fernand Widal
- UMR-S 942, INSERM, University Paris 7 Diderot, Paris, France
| | - Marc Fischler
- Department of Anesthesiology, Hôpital Foch
- Université Versailles Saint-Quentin en Yvelines, Suresnes
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Sun S, Peeters WH, Bezemer R, Long X, Paulussen I, Aarts RM, Noordergraaf GJ. Finger and forehead photoplethysmography-derived pulse-pressure variation and the benefits of baseline correction. J Clin Monit Comput 2018; 33:65-75. [PMID: 29644558 PMCID: PMC6314999 DOI: 10.1007/s10877-018-0140-5] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2017] [Accepted: 04/05/2018] [Indexed: 11/25/2022]
Abstract
To non-invasively predict fluid responsiveness, respiration-induced pulse amplitude variation (PAV) in the photoplethysmographic (PPG) signal has been proposed as an alternative to pulse pressure variation (PPV) in the arterial blood pressure (ABP) signal. However, it is still unclear how the performance of the PPG-derived PAV is site-dependent during surgery. The aim of this study is to compare finger- and forehead-PPG derived PAV in their ability to approach the value and trend of ABP-derived PPV. Furthermore, this study investigates four potential confounding factors, (1) baseline variation, (2) PPV, (3) ratio of respiration and heart rate, and (4) perfusion index, which might affect the agreement between PPV and PAV. In this work, ABP, finger PPG, and forehead PPG were continuously recorded in 29 patients undergoing major surgery in the operating room. A total of 91.2 h data were used for analysis, from which PAV and PPV were calculated and compared. We analyzed the impact of the four factors using a multiple linear regression (MLR) analysis. The results show that compared with the ABP-derived PPV, finger-derived PAV had an agreement of 3.2 ± 5.1%, whereas forehead-PAV had an agreement of 12.0 ± 9.1%. From the MLR analysis, we found that baseline variation was a factor significantly affecting the agreement between PPV and PAV. After correcting for respiration-induced baseline variation, the agreements for finger- and forehead-derived PAV were improved to reach an agreement of − 1.2 ± 3.8% and 3.3 ± 4.8%, respectively. To conclude, finger-derived PAV showed better agreement with ABP-derived PPV compared to forehead-derived PAV. Baseline variation was a factor that significantly affected the agreement between PPV and PAV. By correcting for the baseline variation, improved agreements were obtained for both the finger and forehead, and the difference between these two agreements was diminished. The tracking abilities for both finger- and forehead-derived PAV still warrant improvement for wide use in clinical practice. Overall, our results show that baseline-corrected finger- and forehead-derived PAV may provide a non-invasive alternative for PPV.
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Affiliation(s)
- Shaoxiong Sun
- Department of Electrical Engineering, Eindhoven University of Technology, Eindhoven, The Netherlands.
- Philips Research, Eindhoven, The Netherlands.
| | | | | | - Xi Long
- Department of Electrical Engineering, Eindhoven University of Technology, Eindhoven, The Netherlands
- Philips Research, Eindhoven, The Netherlands
| | - Igor Paulussen
- Philips Research, Eindhoven, The Netherlands
- Elisabeth-Tweesteden Hospital, Tilburg, The Netherlands
| | - Ronald M Aarts
- Department of Electrical Engineering, Eindhoven University of Technology, Eindhoven, The Netherlands
- Philips Research, Eindhoven, The Netherlands
| | - Gerrit J Noordergraaf
- Philips Research, Eindhoven, The Netherlands
- Elisabeth-Tweesteden Hospital, Tilburg, The Netherlands
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11
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Adel A, Awada W, Abdelhamid B, Omar H, Abd El Dayem O, Hasanin A, Rady A. Accuracy and trending of non-invasive hemoglobin measurement during different volume and perfusion statuses. J Clin Monit Comput 2018; 32:1025-1031. [PMID: 29335914 DOI: 10.1007/s10877-018-0101-z] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/23/2017] [Accepted: 01/12/2018] [Indexed: 01/01/2023]
Abstract
The evolution of non-invasive hemoglobin measuring technology would save time and improve transfusion practice. The validity of pulse co-oximetry hemoglobin (SpHb) measurement in the perioperative setting was previously evaluated; however, the accuracy of SpHb in different volume statuses as well as in different perfusion states was not well investigated. The aim of this work is to evaluate the accuracy and trending of SpHb in comparison to laboratory hemoglobin (Lab-Hb) during acute bleeding and after resuscitation. Seventy patients scheduled for major orthopedic procedures with anticipated major blood loss were included. Radical-7 device was used for continuous assessment of SpHb, volume status [via pleth variability index (PVI)] and perfusion status [via perfusion index (PI)]. Lab-Hb and SpHb were measured at three time-points, a baseline reading, after major bleeding, and after resuscitation. Samples were divided into fluid-responsive and fluid non-responsive samples, and were also divided into high-PI and low-PI samples. Accuracy of SpHb was determined using Bland-Altman analysis. Trending of SpHb was evaluated using polar plot analysis. We obtained 210 time-matched readings. Fluid non-responsive samples were 106 (50.5%) whereas fluid responsive samples were 104 (49.5%). Excellent correlation was reported between Lab-Hb and SpHb (r = 0.938). Excellent accuracy with moderate levels of agreement was also reported between both measures among all samples, fluid non-responsive samples, fluid-responsive samples, high-PI samples, and low-PI samples [Mean bias (limits of agreement): 0.01 (- 1.33 and 1.34) g/dL, - 0.08 (- 1.27 and 1.11) g/dL, 0.09 (- 1.36 and 1.54) g/dL, 0.01 (- 1.34 to 1.31) g/dL, and 0.04 (- 1.31 to 1.39) g/dL respectively]. Polar plot analysis showed good trending ability for SpHb as a follow up monitor. In conclusion, SpHb showed excellent correlation with Lab-Hb in fluid responders, fluid non-responders, low-PI, and high PI states. Despite a favorable mean bias of 0.01 g/dL for SpHb, the relatively wide levels of agreement (- 1.3 to 1.3 g/dL) might limit its accuracy. SpHb showed good performance as a trend monitor.
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Affiliation(s)
- Abdelmoneim Adel
- Department of Anesthesia and Critical Care Medicine, Faculty of Medicine, Cairo University, 01 Elsarayah Street, Elmanyal, Cairo, 11559, Egypt
| | - Wael Awada
- Department of Anesthesia and Critical Care Medicine, Faculty of Medicine, Cairo University, 01 Elsarayah Street, Elmanyal, Cairo, 11559, Egypt.,Department of Emergency Medicine, Al-Ghad International College of Applied Health Science, Riyadh, Kingdom of Saudi Arabia
| | - Bassant Abdelhamid
- Department of Anesthesia and Critical Care Medicine, Faculty of Medicine, Cairo University, 01 Elsarayah Street, Elmanyal, Cairo, 11559, Egypt
| | - Heba Omar
- Department of Anesthesia and Critical Care Medicine, Faculty of Medicine, Cairo University, 01 Elsarayah Street, Elmanyal, Cairo, 11559, Egypt
| | - Omnia Abd El Dayem
- Department of Clinical and Chemical Pathology, Cairo University, Cairo, Egypt
| | - Ahmed Hasanin
- Department of Anesthesia and Critical Care Medicine, Faculty of Medicine, Cairo University, 01 Elsarayah Street, Elmanyal, Cairo, 11559, Egypt. .,Department of Critical Care Medicine, Elameen Hospital, Taif, Kingdom of Saudi Arabia.
| | - Ashraf Rady
- Department of Anesthesia and Critical Care Medicine, Faculty of Medicine, Cairo University, 01 Elsarayah Street, Elmanyal, Cairo, 11559, Egypt
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Kher V, Srisawat N, Noiri E, Benghanem Gharbi M, Shetty MS, Yang L, Bagga A, Chakravarthi R, Mehta R. Prevention and Therapy of Acute Kidney Injury in the Developing World. Kidney Int Rep 2017. [PMCID: PMC5720672 DOI: 10.1016/j.ekir.2017.03.015] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Timely recognition of patients at risk or with possible acute kidney injury (AKI) is essential for early intervention to minimize further damage and improve outcome. Initial management of patients with suspected and persistent AKI should include thorough clinical assessment of all patients with AKI to identify reversible factors, including fluid volume status, potential nephrotoxins, and an assessment of the underlying health of the kidney. Based on these assessments, early interventions to provide appropriate and adequate fluid resuscitation while avoiding fluid overload, removal of nephrotoxins, and adjustment of drug doses according to the level of kidney function derangement are important. The judicious use of diuretics for fluid overload and/or in cardiac decompensated patients and introduction of early enteral nutritional support need to be considered to improve outcomes in AKI. Although these basic principles are well recognized, their application in clinical practice in low resource settings is often limited due to lack of education, availability of resources, and lack of trained personnel, which limits access to care. We report the consensus recommendations of the 18th Acute Dialysis Quality Initiative meeting in Hyderabad, India, on strategies to evaluate patients with suspected AKI and initiate measures for prevention and management to improve outcomes, particularly in low resource settings. These recomendations provide a framework for caregivers, who are often primary care physicians, nurses, and other allied healthcare personnel, to manage patients with AKI in resource poor countries.
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Alvarado Sánchez JI, Amaya Zúñiga WF, Monge García MI. Predictors to Intravenous Fluid Responsiveness. J Intensive Care Med 2017. [DOI: https://doi.org/10.1177/0885066617709434] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Management with intravenous fluids can improve cardiac output in some surgical patients. Management with static preload indicators, such as central venous pressure and pulmonary artery occlusion pressure, has not demonstrated a suitable relationship with changes in the cardiac output induced by intravenous fluid therapy. Dynamic indicators, such as the variability of arterial pulse pressure or stroke volume variation, have demonstrated a suitable relationship. Since improvement in cardiac output does not guarantee an adequate perfusion pressure, in patients with hypotension, it is also necessary to know whether arterial pressure will also increase with intravenous fluid therapy. In this regard, the functional assessment of arterial load by dynamic arterial elastance could help to determine which patients will improve not only their cardiac output but also their mean arterial pressure.
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Affiliation(s)
- Jorge Iván Alvarado Sánchez
- Department of Physiology, Universidad Nacional De Colombia, Bogota, Colombia
- Department of Anesthesiology, Centro Policlínico del Olaya, Bogota, Colombia
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Alvarado Sánchez JI, Amaya Zúñiga WF, Monge García MI. Predictors to Intravenous Fluid Responsiveness. J Intensive Care Med 2017; 33:227-240. [PMID: 28506136 DOI: 10.1177/0885066617709434] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Management with intravenous fluids can improve cardiac output in some surgical patients. Management with static preload indicators, such as central venous pressure and pulmonary artery occlusion pressure, has not demonstrated a suitable relationship with changes in the cardiac output induced by intravenous fluid therapy. Dynamic indicators, such as the variability of arterial pulse pressure or stroke volume variation, have demonstrated a suitable relationship. Since improvement in cardiac output does not guarantee an adequate perfusion pressure, in patients with hypotension, it is also necessary to know whether arterial pressure will also increase with intravenous fluid therapy. In this regard, the functional assessment of arterial load by dynamic arterial elastance could help to determine which patients will improve not only their cardiac output but also their mean arterial pressure.
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Affiliation(s)
- Jorge Iván Alvarado Sánchez
- 1 Department of Physiology, Universidad Nacional De Colombia, Bogota, Colombia.,2 Department of Anesthesiology, Centro Policlínico del Olaya, Bogota, Colombia
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Abstract
PURPOSE OF REVIEW Standard hemodynamic monitoring such as heart rate and systemic blood pressure may only provide a crude estimation of organ perfusion during neonatal intensive care. Pulse oximetry monitoring allows for continuous noninvasive monitoring of hemoglobin oxygenation and thus provides estimation of end-organ oxygenation. This review aims to provide an overview of pulse oximetry and discuss its current and potential clinical use during neonatal intensive care. RECENT FINDINGS Technological advances in continuous assessment of dynamic changes in systemic oxygenation with pulse oximetry during transition to extrauterine life and beyond provide additional details about physiological interactions among the key hemodynamic factors regulating systemic blood flow distribution along with the subtle changes that are frequently transient and undetectable with standard monitoring. SUMMARY Noninvasive real-time continuous systemic oxygen monitoring has the potential to serve as biomarkers for early-organ dysfunction, to predict adverse short-term and long-term outcomes in critically ill neonates, and to optimize outcomes. Further studies are needed to establish values predicting adverse outcomes and to validate targeted interventions to normalize abnormal values to improve outcomes.
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Abstract
PURPOSE OF REVIEW Evidence-based fluid therapy is complicated by blurred boundaries toward other fields of therapy and the majority of trials not focusing on patient-relevant outcomes. Additionally, recent trials unsettled the faith in traditional concepts on fluid therapy. The article reviews the evidence on diagnosis and treatment of hypovolemia and discusses the use of balanced solutions and early goal-directed therapy (EGDT) in septic shock resuscitation. RECENT FINDINGS Hypovolemia should be diagnosed and its treatment guided by a multifaceted approach, including medical history, physical examination, volume responsiveness, and technical parameters - dynamic indicators, volumetric indicators, sonography, and metabolic indicators. Central venous pressure and pulmonary artery occlusion pressure should be avoided. In ICU patients, balanced crystalloids should primarily be used, because unbalanced infusions (especially saline) cause hyperchloremic acidosis which is associated with renal impairment and infections. Colloids are beneficial to restore blood volume rapidly. Hydroxyethyl starch may be harmful although the validity of the respective recent studies is limited by methodological flaws. Early aggressive fluid therapy is still beneficial in septic shock resuscitation, despite recent trials challenging the EGDT concept. Today, 10 years after Rivers, 'usual care' includes aggressive fluid resuscitation that is as effective as formal EGDT. SUMMARY Evidence-based fluid therapy includes a multifaceted diagnostic approach, the primary use of balanced crystalloids and early aggressive (septic) shock resuscitation.
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Theerawit P, Morasert T, Sutherasan Y. Inferior vena cava diameter variation compared with pulse pressure variation as predictors of fluid responsiveness in patients with sepsis. J Crit Care 2016; 36:246-251. [PMID: 27591389 DOI: 10.1016/j.jcrc.2016.07.023] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2016] [Revised: 07/23/2016] [Accepted: 07/23/2016] [Indexed: 10/21/2022]
Abstract
BACKGROUND Currently, physicians employ pulse pressure variation (PPV) as a gold standard for predicting fluid responsiveness. However, employing ultrasonography in intensive care units is increasing, including using the ultrasonography for assessment of fluid responsiveness. Data comparing the performance of both methods are still lacking. This is the reason for the present study. MATERIALS AND METHODS We conducted a prospective observational study in patients with sepsis requiring fluid challenge. The PPV, inferior vena cava diameter variation (IVDV), stroke volume variation (SVV), and the other hemodynamic variables were recorded before and after fluid challenges. Fluid responders were identified when cardiac output increased more than 15% after fluid loading. RESULTS A total of 29 patients with sepsis were enrolled in this study. Sixteen (55.2%) were fluid responders. Threshold values to predict fluid responsiveness were 13.8% of PPV (sensitivity 100% and specificity 84.6%), 10.2% of IVDV (sensitivity 75% and specificity 76.9%) and 10.7% of SVV (sensitivity 81.3% and specificity 76.9%). The area under the curves of receiver operating characteristic showed that PPV (0.909, 95% confidence interval [CI], 0.784-1.00) and SVV (0.812, 95% CI, 0.644-0.981) had greater performance than IVDV (0.688, 95% CI, 0.480-0.895) regarding fluid responsiveness assessment. CONCLUSIONS The present study demonstrated better performance of the PPV than the IVDV. A threshold value more than 10% may be used for identifying fluid responders.
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Affiliation(s)
- Pongdhep Theerawit
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Faculty of Medicine Ramathibodi Hospital, Mahidol University, Bangkok, 270, Rama 6 Road, Thung Phaya Thai, Ratchathewi, Bangkok 10400, Thailand.
| | - Thotsaporn Morasert
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Faculty of Medicine Ramathibodi Hospital, Mahidol University, Bangkok, 270, Rama 6 Road, Thung Phaya Thai, Ratchathewi, Bangkok 10400, Thailand.
| | - Yuda Sutherasan
- Division of Pulmonary and Critical Care Medicine, Department of Medicine, Faculty of Medicine Ramathibodi Hospital, Mahidol University, Bangkok, 270, Rama 6 Road, Thung Phaya Thai, Ratchathewi, Bangkok 10400, Thailand.
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Marx G, Schindler AW, Mosch C, Albers J, Bauer M, Gnass I, Hobohm C, Janssens U, Kluge S, Kranke P, Maurer T, Merz W, Neugebauer E, Quintel M, Senninger N, Trampisch HJ, Waydhas C, Wildenauer R, Zacharowski K, Eikermann M. Intravascular volume therapy in adults: Guidelines from the Association of the Scientific Medical Societies in Germany. Eur J Anaesthesiol 2016; 33:488-521. [PMID: 27043493 PMCID: PMC4890839 DOI: 10.1097/eja.0000000000000447] [Citation(s) in RCA: 72] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Affiliation(s)
- Gernot Marx
- From the Department of Cardiothoracic and Vascular Surgery, University Medical Centre of the Johannes Gutenberg University Mainz, Mainz (JA); Department of Anaesthesiology and Intensive Care Medicine, Jena University Hospital, Jena (MB); Institute for Research in Operative Medicine, Witten/Herdecke University, Cologne (ME); Institute of Nursing Science and Practice, Paracelsus Private Medical University, Salzburg, Austria (IG); Department of Internal Medicine, Neurology and Dermatology, Leipzig University Hospital, Leibzig (CH); Department of Cardiology, St Antonius Hospital, Eschweiler (UJ); Centre for Intensive Care Medicine, Universitätsklinikum, Hamburg-Eppendorf (SK); Department of Anaesthesia and Critical Care, University Hospital of Würzburg, Würzburg (PK); Department of Intensive and Intermediate Care Medicine, University Hospital of RWTH Aachen, Aachen (GM); Urological Unit and Outpatient Clinic, University Hospital rechts der Isar, Munich (TM); Department of Obstetrics and Gynaecology, Bonn University Hospital, Bonn (WM); Institute for Research in Operative Medicine (IFOM), Witten/Herdecke University, Cologne (CM, EN); Department of Anaesthesiology, University Medical Centre Göttingen, Göttingen (MQ); Department of Intensive and Intermediate Care Medicine, University Hospital of RWTH Aachen, Aachen (AWS); Department of General and Visceral Surgery, Münster University Hospital, Münster (NS); Department of Health Informatics, Biometry and Epidemiology, Ruhr-Universität Bochum, Bochum (HJT); Department of Trauma Surgery, Essen University Hospital, Essen (CW); Department of General Surgery, University Hospital of Würzburg, Würzburg (RW); and Department of Anaesthesia, Intensive Care Medicine and Pain Therapy, University Hospital Frankfurt, Frankfurt, Germany (KZ)
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Biais M, Stecken L, Martin A, Roullet S, Quinart A, Sztark F. Automated, continuous and non-invasive assessment of pulse pressure variations using CNAP ® system. J Clin Monit Comput 2016; 31:685-692. [PMID: 27312841 DOI: 10.1007/s10877-016-9899-4] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2015] [Accepted: 06/10/2016] [Indexed: 10/21/2022]
Abstract
Non-invasive respiratory variations in arterial pulse pressure using infrared-plethysmography (PPVCNAP) are able to predict fluid responsiveness in mechanically ventilated patients. However, they cannot be continuously monitored. The present study evaluated a new algorithm allowing continuous measurements of PPVCNAP (PPVCNAPauto) (CNSystem, Graz, Austria). Thirty-five patients undergoing vascular surgery were studied after induction of general anaesthesia. Stroke volume was measured using the VigileoTM/FloTracTM. Invasive pulse pressure variations were manually calculated using an arterial line (PPVART) and PPVCNAPauto was continuously displayed. PPVART and PPVCNAPauto were simultaneously recorded before and after volume expansion (500 ml hydroxyethylstarch). Subjects were defined as responders if stroke volume increased by ≥15 %. Twenty-one patients were responders. Before volume expansion, PPVART and PPVCNAPauto exhibited a bias of 0.1 % and limits of agreement from -7.9 % to 7.9 %. After volume expansion, PPVART and PPVCNAPauto exhibited a bias of -0.4 % and limits of agreement from -5.3 % to 4.5 %. A 14 % baseline PPVART threshold discriminated responders with a sensitivity of 86 % (95 % CI 64-97 %) and a specificity of 100 % (95 % CI 77-100 %). Area under the receiver operating characteristic (ROC) curve for PPVART was 0.93 (95 % CI 0.79-0.99). A 15 % baseline PPVCNAPauto threshold discriminated responders with a sensitivity of 76% (95 % CI 53-92 %) and a specificity of 93 % (95 % CI 66-99 %). Area under the ROC curves for PPVCNAPauto was 0.91 (95 % CI 0.76-0.98), which was not different from that for PPVART. When compared with PPVART, PPVCNAPauto performs satisfactorily in assessing fluid responsiveness in hemodynamically stable surgical patients.
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Affiliation(s)
- Matthieu Biais
- Service d'Anesthésie Réanimation 3, CFXM, CHU de Bordeaux, 33076, Bordeaux Cedex, France. .,Adaptation cardiovasculaire à l'ischémie, U1034, INSERM, 33600, Pessac, France. .,Adaptation cardiovasculaire à l'ischémie, U1034, Univ. Bordeaux, 33600, Pessac, France.
| | - Laurent Stecken
- Service d'Anesthésie réanimation 1, CHU de Bordeaux, 33000, Bordeaux, France
| | - Aurélie Martin
- Service d'Anesthésie réanimation 1, CHU de Bordeaux, 33000, Bordeaux, France
| | - Stéphanie Roullet
- Service d'Anesthésie réanimation 1, CHU de Bordeaux, 33000, Bordeaux, France
| | - Alice Quinart
- Service d'Anesthésie réanimation 1, CHU de Bordeaux, 33000, Bordeaux, France
| | - François Sztark
- Adaptation cardiovasculaire à l'ischémie, U1034, INSERM, 33600, Pessac, France.,Adaptation cardiovasculaire à l'ischémie, U1034, Univ. Bordeaux, 33600, Pessac, France.,Service d'Anesthésie réanimation 1, CHU de Bordeaux, 33000, Bordeaux, France
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Ventilation-Induced Modulation of Pulse Oximeter Waveforms: A Method for the Assessment of Early Changes in Intravascular Volume During Spinal Fusion Surgery in Pediatric Patients. Anesth Analg 2016; 123:346-56. [PMID: 27284998 DOI: 10.1213/ane.0000000000001377] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
BACKGROUND Scoliosis surgery is often associated with substantial blood loss, requiring fluid resuscitation and blood transfusions. In adults, dynamic preload indices have been shown to be more reliable for guiding fluid resuscitation, but these indices have not been useful in children undergoing surgery. The aim of this study was to introduce frequency-analyzed photoplethysmogram (PPG) and arterial pressure waveform variables and to study the ability of these parameters to detect early bleeding in children during surgery. METHODS We studied 20 children undergoing spinal fusion. Electrocardiogram, arterial pressure, finger pulse oximetry (finger PPG), and airway pressure waveforms were analyzed using time domain and frequency domain methods of analysis. Frequency domain analysis consisted of calculating the amplitude density of PPG and arterial pressure waveforms at the respiratory and cardiac frequencies using Fourier analysis. This generated 2 measurements: The first is related to slow mean arterial pressure modulation induced by ventilation (also known as DC modulation when referring to the PPG), and the second corresponds to pulse pressure modulation (AC modulation or changes in the amplitude of pulse oximeter plethysmograph when referring to the PPG). Both PPG and arterial pressure measurements were divided by their respective cardiac pulse amplitude to generate DC% and AC% (normalized values). Standard hemodynamic data were also recorded. Data at baseline and after bleeding (estimated blood loss about 9% of blood volume) were presented as median and interquartile range and compared using Wilcoxon signed-rank tests; a Bonferroni-corrected P value <0.05 was considered statistically significant. RESULTS There were significant increases in PPG DC% (median [interquartile range] = 359% [210 to 541], P = 0.002), PPG AC% (160% [87 to 251], P = 0.003), and arterial DC% (44% [19 to 84], P = 0.012) modulations, respectively, whereas arterial AC% modulations showed nonsignificant increase (41% [1 to 85], P = 0.12). The change in PPG DC% was significantly higher than that in PPG AC%, arterial DC%, arterial AC%, and systolic blood pressure with P values of 0.008, 0.002, 0.003, and 0.002, respectively. Only systolic blood pressure showed significant changes (11% [4 to 21], P = 0.003) between bleeding phase and baseline. CONCLUSIONS Finger PPG and arterial waveform parameters (using frequency analysis) can track changes in blood volume during the bleeding phase, suggesting the potential for a noninvasive monitor for tracking changes in blood volume in pediatric patients. PPG waveform baseline modulation (PPG DC%) was more sensitive to changes in venous blood volume when compared with respiration-induced modulation seen in the arterial pressure waveform.
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DeBarros M, Causey MW, Chesley P, Martin M. Reliability of Continuous Non-Invasive Assessment of Hemoglobin and Fluid Responsiveness: Impact of Obesity and Abdominal Insufflation Pressures. Obes Surg 2016; 25:1142-8. [PMID: 25399349 DOI: 10.1007/s11695-014-1505-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
BACKGROUND During surgery, proper fluid resuscitation and hemostatic control is critical. Pleth variability index (PVI) is advocated as a reliable way of optimizing intraoperative fluid resuscitation. PVI is a measure of dynamic change in perfusion index during a complete respiratory cycle. Non-invasive monitoring of total hemoglobin could provide a reliable means to determine need for transfusion. We analyzed the impact of insufflation and obesity on non-invasive measurements of hemoglobin and PVI in laparoscopic procedures to validate reliability of fluid responsiveness and hemoglobin levels. METHODS A non-invasive hemoglobin and PVI monitoring device was prospectively analyzed in patients undergoing abdominal operations. Patients were stratified by open and laparoscopic approach and obesity (body mass index (BMI) ≥35). PVI and hemoglobin values were assessed before, during, and after insufflation and compared to control patients undergoing open surgery. RESULTS Sixty-three patients were enrolled (mean age 42 years; 71 % male; mean BMI 36) with 24 patients laparoscopic non-obese (LNO), 20 laparoscopic obese (LO), and 19 undergoing open operations. There was no significant blood loss. Hemoglobin did not change significantly before or after insufflation. There was false elevation of PVI with insufflation and more pronounced in obese patients. CONCLUSIONS Insufflation or obesity was not associated with significant variations in hemoglobin. Non-invasive monitoring of hemoglobin is useful in laparoscopic procedures in obese and non-obese patients. PVI values should be used cautiously during laparoscopic procedures, particularly in obese patients.
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Affiliation(s)
- Mia DeBarros
- Department of Surgery, Madigan Army Medical Center, 9040a Fitzsimmons Drive, Tacoma, WA, 98431, USA,
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Perel A. Non-invasive monitoring of oxygen delivery in acutely ill patients: new frontiers. Ann Intensive Care 2015; 5:24. [PMID: 26380992 PMCID: PMC4573965 DOI: 10.1186/s13613-015-0067-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2015] [Accepted: 09/06/2015] [Indexed: 12/15/2022] Open
Abstract
Hypovolemia, anemia and hypoxemia may cause critical deterioration in the oxygen delivery (DO2). Their early detection followed by a prompt and appropriate intervention is a cornerstone in the care of critically ill patients. And yet, the remedies for these life-threatening conditions, namely fluids, blood and oxygen, have to be carefully titrated as they are all associated with severe side-effects when administered in excess. New technological developments enable us to monitor the components of DO2 in a continuous non-invasive manner via the sensor of the traditional pulse oximeter. The ability to better assess oxygenation, hemoglobin levels and fluid responsiveness continuously and simultaneously may be of great help in managing the DO2. The non-invasive nature of this technology may also extend the benefits of advanced monitoring to wider patient populations.
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Affiliation(s)
- Azriel Perel
- Anesthesiology and Intensive Care, Sheba Medical Center, Tel Aviv University, 52621, Tel Aviv, Israel.
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Respiratory modulations in the photoplethysmogram (DPOP) as a measure of respiratory effort. J Clin Monit Comput 2015; 30:595-602. [PMID: 26377021 PMCID: PMC5023749 DOI: 10.1007/s10877-015-9763-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2015] [Accepted: 08/28/2015] [Indexed: 12/03/2022]
Abstract
DPOP is a measure of the strength of respiratory modulations present in the pulse oximetry photoplethysmogram (pleth) waveform. It has been proposed as a non-invasive parameter for the prediction of the response to volume expansion in hypovolemic patients. The effect of resistive breathing on the DPOP parameter was studied to determine whether it may have an adjunct use as a measure of respiratory effort. Healthy volunteers were tasked to breathe at fixed respiratory rates over a range of airway resistances generated by a flow resistor inserted within a mouthpiece. Changes in respiratory efforts, effected by the subjects and measured as airway pressures at the mouth, were compared to DPOP values derived from a finger pulse oximeter probe. It was found that the increased effort to breathe manifests itself as an associated increase in DPOP. Further, a relationship between DPOP and percent modulation of the pleth waveform was observed. A version of the DPOP algorithm that corrects for low perfusion was implemented which resulted in an improved relationship between DPOP and PPV. Although a limited cohort of seven volunteers was used, the results suggest that DPOP may be useful as a respiratory effort parameter, given that the fluid level of the patient is maintained at a constant level over the period of analysis.
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Feissel M, Aho LS, Georgiev S, Tapponnier R, Badie J, Bruyère R, Quenot JP. Pulse Wave Transit Time Measurements of Cardiac Output in Septic Shock Patients: A Comparison of the Estimated Continuous Cardiac Output System with Transthoracic Echocardiography. PLoS One 2015; 10:e0130489. [PMID: 26126112 PMCID: PMC4488420 DOI: 10.1371/journal.pone.0130489] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/19/2015] [Accepted: 05/19/2015] [Indexed: 12/29/2022] Open
Abstract
Background We determined reliability of cardiac output (CO) measured by pulse wave transit time cardiac output system (esCCO system; COesCCO) vs transthoracic echocardiography (COTTE) in mechanically ventilated patients in the early phase of septic shock. A secondary objective was to assess ability of esCCO to detect change in CO after fluid infusion. Methods Mechanically ventilated patients admitted to the ICU, aged >18 years, in sinus rhythm, in the early phase of septic shock were prospectively included. We performed fluid infusion of 500ml of crystalloid solution over 20 minutes and recorded CO by EsCCO and TTE immediately before (T0) and 5 minutes after (T1) fluid administration. Patients were divided into 2 groups (responders and non-responders) according to a threshold of 15% increase in COTTE in response to volume expansion. Results In total, 25 patients were included, average 64±15 years, 15 (60%) were men. Average SAPSII and SOFA scores were 55±21.3 and 13±2, respectively. ICU mortality was 36%. Mean cardiac output at T0 was 5.8±1.35 L/min by esCCO and 5.27±1.17 L/min by COTTE. At T1, respective values were 6.63 ± 1.57 L/min for esCCO and 6.10±1.29 L/min for COTTE. Overall, 12 patients were classified as responders, 13 as non-responders by the reference method. A threshold of 11% increase in COesCCO was found to discriminate responders from non-responders with a sensitivity of 83% (95% CI, 0.52-0.98) and a specificity of 77% (95% CI, 0.46-0.95). Conclusion We show strong correlation esCCO and echocardiography for measuring CO, and change in CO after fluid infusion in ICU patients.
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Affiliation(s)
- Marc Feissel
- Service de Réanimation, Maladies Infectieuses, Centre Hospitalier de Belfort-Montbéliard, Belfort, France
| | - Ludwig Serge Aho
- Service d’Epidémiologie et d’Hygiène Hospitalière, Centre Hospitalier Universitaire de Dijon, Bocage Central, Dijon, France
| | - Stefan Georgiev
- Service de Réanimation, Maladies Infectieuses, Centre Hospitalier de Belfort-Montbéliard, Belfort, France
| | - Romain Tapponnier
- Service de Réanimation, Maladies Infectieuses, Centre Hospitalier de Belfort-Montbéliard, Belfort, France
| | - Julio Badie
- Service de Réanimation, Maladies Infectieuses, Centre Hospitalier de Belfort-Montbéliard, Belfort, France
| | - Rémi Bruyère
- Service de Réanimation Médicale, Centre Hospitalier Universitaire de Dijon, Bocage Central, Dijon, France
- INSERM Centre de Recherche UMR866, Université de Bourgogne, Dijon, France
| | - Jean-Pierre Quenot
- Service de Réanimation Médicale, Centre Hospitalier Universitaire de Dijon, Bocage Central, Dijon, France
- INSERM Centre de Recherche UMR1347, Université de Bourgogne, Dijon, France
- * E-mail:
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On better estimating and normalizing the relationship between clinical parameters: comparing respiratory modulations in the photoplethysmogram and blood pressure signal (DPOP versus PPV). COMPUTATIONAL AND MATHEMATICAL METHODS IN MEDICINE 2015; 2015:576340. [PMID: 25691912 PMCID: PMC4322304 DOI: 10.1155/2015/576340] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/22/2014] [Accepted: 12/11/2014] [Indexed: 12/02/2022]
Abstract
DPOP (ΔPOP or Delta-POP) is a noninvasive parameter which measures the strength of respiratory modulations present in the pulse oximeter waveform. It has been proposed as a noninvasive alternative to pulse pressure variation (PPV) used in the prediction of the response to volume expansion in hypovolemic patients. We considered a number of simple techniques for better determining the underlying relationship between the two parameters. It was shown numerically that baseline-induced signal errors were asymmetric in nature, which corresponded to observation, and we proposed a method which combines a least-median-of-squares estimator with the requirement that the relationship passes through the origin (the LMSO method). We further developed a method of normalization of the parameters through rescaling DPOP using the inverse gradient of the linear fitted relationship. We propose that this normalization method (LMSO-N) is applicable to the matching of a wide range of clinical parameters. It is also generally applicable to the self-normalizing of parameters whose behaviour may change slightly due to algorithmic improvements.
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Oxymétrie pulsée : contribution au diagnostic et à l’approche hémodynamique en pédiatrie. MEDECINE INTENSIVE REANIMATION 2015. [DOI: 10.1007/s13546-014-1004-8] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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A Review of Signal Processing Used in the Implementation of the Pulse Oximetry Photoplethysmographic Fluid Responsiveness Parameter. Anesth Analg 2014; 119:1293-306. [DOI: 10.1213/ane.0000000000000392] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Yang X, Du B. Does pulse pressure variation predict fluid responsiveness in critically ill patients? A systematic review and meta-analysis. CRITICAL CARE : THE OFFICIAL JOURNAL OF THE CRITICAL CARE FORUM 2014; 18:650. [PMID: 25427970 PMCID: PMC4258282 DOI: 10.1186/s13054-014-0650-6] [Citation(s) in RCA: 138] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/29/2014] [Accepted: 11/06/2014] [Indexed: 02/08/2023]
Abstract
Introduction Fluid resuscitation is crucial in managing hemodynamically unstable patients. The last decade witnessed the use of pulse pressure variation (PPV) to predict fluid responsiveness. However, as far as we know, no systematic review and meta-analysis has been carried out to evaluate the value of PPV in predicting fluid responsiveness specifically upon patients admitted into intensive care units. Methods We searched MEDLINE and EMBASE and included clinical trials that evaluated the association between PPV and fluid responsiveness after fluid challenge in mechanically ventilated patients in intensive care units. Data were synthesized using an exact binomial rendition of the bivariate mixed-effects regression model modified for synthesis of diagnostic test data. Result Twenty-two studies with 807 mechanically ventilated patients with tidal volume more than 8 ml/kg and without spontaneous breathing and cardiac arrhythmia were included, and 465 were responders (58%). The pooled sensitivity was 0.88 (95% confidence interval (CI) 0.81 to 0.92) and pooled specificity was 0.89 (95% CI 0.84 to 0.92). A summary receiver operating characteristic curve yielded an area under the curve of 0.94 (95% CI 0.91 to 0.95). A significant threshold effect was identified. Conclusions PPV predicts fluid responsiveness accurately in mechanically ventilated patients with relative large tidal volume and without spontaneous breathing and cardiac arrhythmia. Electronic supplementary material The online version of this article (doi:10.1186/s13054-014-0650-6) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Xiaobo Yang
- Medical ICU, Peking Union Medical College Hospital, Peking Union Medical College and Chinese Academy of Medical Sciences, 1 Shuai Fu Yuan, Beijing, 100730, PR China.
| | - Bin Du
- Medical ICU, Peking Union Medical College Hospital, Peking Union Medical College and Chinese Academy of Medical Sciences, 1 Shuai Fu Yuan, Beijing, 100730, PR China.
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Exadaktylos A, Braun CT, Ziaka M. Pulse CO-oximetry – Clinical impact in the emergency department. TRENDS IN ANAESTHESIA AND CRITICAL CARE 2014. [DOI: 10.1016/j.tacc.2014.07.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Addison PS, Wang R, Uribe AA, Bergese SD. Increasing signal processing sophistication in the calculation of the respiratory modulation of the photoplethysmogram (DPOP). J Clin Monit Comput 2014; 29:363-72. [PMID: 25209132 PMCID: PMC4420848 DOI: 10.1007/s10877-014-9613-3] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/18/2014] [Accepted: 08/27/2014] [Indexed: 11/07/2022]
Abstract
DPOP (∆POP or Delta-POP) is a non-invasive parameter which measures the strength of respiratory modulations present in the pulse oximetry photoplethysmogram (pleth) waveform. It has been proposed as a non-invasive surrogate parameter for pulse pressure variation (PPV) used in the prediction of the response to volume expansion in hypovolemic patients. Many groups have reported on the DPOP parameter and its correlation with PPV using various semi-automated algorithmic implementations. The study reported here demonstrates the performance gains made by adding increasingly sophisticated signal processing components to a fully automated DPOP algorithm. A DPOP algorithm was coded and its performance systematically enhanced through a series of code module alterations and additions. Each algorithm iteration was tested on data from 20 mechanically ventilated OR patients. Correlation coefficients and ROC curve statistics were computed at each stage. For the purposes of the analysis we split the data into a manually selected ‘stable’ region subset of the data containing relatively noise free segments and a ‘global’ set incorporating the whole data record. Performance gains were measured in terms of correlation against PPV measurements in OR patients undergoing controlled mechanical ventilation. Through increasingly advanced pre-processing and post-processing enhancements to the algorithm, the correlation coefficient between DPOP and PPV improved from a baseline value of R = 0.347 to R = 0.852 for the stable data set, and, correspondingly, R = 0.225 to R = 0.728 for the more challenging global data set. Marked gains in algorithm performance are achievable for manually selected stable regions of the signals using relatively simple algorithm enhancements. Significant additional algorithm enhancements, including a correction for low perfusion values, were required before similar gains were realised for the more challenging global data set.
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Affiliation(s)
- Paul S Addison
- Advanced Research Group, Covidien Respiratory and Monitoring Solutions, The Technopole Centre, Edinburgh, EH26 0PJ, Scotland, UK,
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Greenfield N, Balk RA. Evaluating the adequacy of fluid resuscitation in patients with septic shock: controversies and future directions. Hosp Pract (1995) 2014; 40:147-57. [PMID: 22615089 DOI: 10.3810/hp.2012.04.980] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Fluid resuscitation is a cornerstone in the treatment of severe sepsis and septic shock. However, there is little evidence to guide clinicians in its administration. Current guidelines recommend targeting fluid therapy based on measurements of cardiac filling pressures, such as central venous pressure. Static pressures are poor predictors of a patient's response to fluid. Such response can be better predicted by measuring changes in hemodynamic parameters caused by positive pressure ventilation or maneuvers designed to simulate increased preload. These changes can be measured by analysis of arterial waveforms, echocardiography or Doppler, or with emerging noninvasive technologies. This article reviews the current role of fluid replacement strategies and the use of monitoring systems in the overall resuscitation of patients with severe sepsis and septic shock.
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Affiliation(s)
- Neal Greenfield
- Division of Pulmonary and Critical Care Medicine, Department of Internal Medicine, Rush Medical College, Chicago, IL
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Calculation of the Respiratory Modulation of the Photoplethysmogram (DPOP) Incorporating a Correction for Low Perfusion. Anesthesiol Res Pract 2014; 2014:980149. [PMID: 25177348 PMCID: PMC4142304 DOI: 10.1155/2014/980149] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2014] [Accepted: 06/20/2014] [Indexed: 11/17/2022] Open
Abstract
DPOP quantifies respiratory modulations in the photoplethysmogram. It has been proposed as a noninvasive surrogate for pulse pressure variation (PPV) used in the prediction of the response to volume expansion in hypovolemic patients. The correlation between DPOP and PPV may degrade due to low perfusion effects. We implemented an automated DPOP algorithm with an optional correction for low perfusion. These two algorithm variants (DPOPa and DPOPb) were tested on data from 20 mechanically ventilated OR patients split into a benign "stable region" subset and a whole record "global set." Strong correlation was found between DPOP and PPV for both algorithms when applied to the stable data set: R = 0.83/0.85 for DPOPa/DPOPb. However, a marked improvement was found when applying the low perfusion correction to the global data set: R = 0.47/0.73 for DPOPa/DPOPb. Sensitivities, Specificities, and AUCs were 0.86, 0.70, and 0.88 for DPOPa/stable region; 0.89, 0.82, and 0.92 for DPOPb/stable region; 0.81, 0.61, and 0.73 for DPOPa/global region; 0.83, 0.76, and 0.86 for DPOPb/global region. An improvement was found in all results across both data sets when using the DPOPb algorithm. Further, DPOPb showed marked improvements, both in terms of its values, and correlation with PPV, for signals exhibiting low percent modulations.
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Wu Y, Zhou S, Zhou Z, Liu B. A 10-second fluid challenge guided by transthoracic echocardiography can predict fluid responsiveness. CRITICAL CARE : THE OFFICIAL JOURNAL OF THE CRITICAL CARE FORUM 2014; 18:R108. [PMID: 24886990 PMCID: PMC4075154 DOI: 10.1186/cc13891] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 11/16/2013] [Accepted: 05/12/2014] [Indexed: 12/29/2022]
Abstract
Introduction The accurate assessment of intravascular volume status for the therapy of severe hypovolemia and shock is difficult and critical to critically ill patients. Non-invasive evaluation of fluid responsiveness by the rapid infusion of a very limited amount of volume is an important clinical goal. This study aimed to test whether echocardiographic parameters could predict fluid responsiveness in critically ill patients following a low-volume (50-ml crystalloid solution) infusion over 10 seconds. Methods We prospectively studied 55 mechanically ventilated patients. Echocardiography was performed during a 50-ml infusion of crystalloid solution over 10 seconds and a further 450 ml over 15 minutes. Cardiac output (CO), stroke volume (SV), aortic velocity time index (VTI), and left ventricular ejection fraction (LVEF) were recorded. Patients were classified as responders (Rs) if CO increased by at least 15% following the 500-ml volume expansion or were classified as non-responders (NRs) if CO increased by less than 15%. Area under the receiver operating characteristic curves (AUC) compared CO variations after 50 ml over 10 seconds (∆CO50) and 500 ml over 15 minutes (∆CO500) and the variation of VTI after infusion of 50 ml of fluid over 10 seconds (∆VTI50). Results In total, 50 patients were enrolled, and 27 (54%) of them were Rs. General characteristics, LVEF, heart rate, and central venous pressure were similar between Rs and NRs. In the Rs group, the AUC for ∆CO50 was 0.95 ± 0.03 (P <0.01; best cutoff value, 6%; sensitivity, 93%; specificity, 91%). Moreover, ∆CO50 and ∆CO500 were strongly correlated (r = 0.87; P <0.01). The AUC for ∆VTI50 was 0.91 ± 0.04 (P <0.01; best cutoff value, 9%; sensitivity, 74%; specificity, 95%). ∆VTI50 and ∆CO500 were positively correlated (r = 0.72; P <0.01). Conclusion In critically ill patients, the variation of CO and VTI after the administration of 50-ml crystalloid solution over 10 seconds (∆CO50 and ∆VTI50) can accurately predict fluid responsiveness. Trial registration Current Controlled Trials ISRCTN10524328. Registered 12 December 2013.
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Narasimhan M, J Koenig S, Mayo PH. Advanced echocardiography for the critical care physician: part 2. Chest 2014; 145:135-142. [PMID: 24394824 DOI: 10.1378/chest.12-2442] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023] Open
Abstract
This article is the second part of a series that describes practical techniques in advanced critical care echocardiography and their use in the management of hemodynamic instability. Measurement of left ventricular function and segmental wall motion abnormalities, evaluation of left ventricular filling pressures, assessment of right-sided heart function, and determination of preload sensitivity, including passive leg raising, are discussed. Video examples help to demonstrate techniques described in the text.
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Affiliation(s)
- Mangala Narasimhan
- Division of Pulmonary, Critical Care and Sleep Medicine, the Hofstra North Shore LIJ School of Medicine, New Hyde Park, NY.
| | - Seth J Koenig
- Division of Pulmonary, Critical Care and Sleep Medicine, the Hofstra North Shore LIJ School of Medicine, New Hyde Park, NY
| | - Paul H Mayo
- Division of Pulmonary, Critical Care and Sleep Medicine, the Hofstra North Shore LIJ School of Medicine, New Hyde Park, NY
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Baker AK, Partridge RJO, Litton E, Ho KM. Assessment of the plethysmographic variability index as a predictor of fluid responsiveness in critically ill patients: a pilot study. Anaesth Intensive Care 2014; 41:736-41. [PMID: 24180714 DOI: 10.1177/0310057x1304100608] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Optimising intravascular volume in patients with hypotension requiring vasopressor support is a key challenge of critical care medicine. The optimal haemodynamic parameter to assess fluid responsiveness in critically ill patients, particularly those requiring a noradrenaline infusion and mechanical ventilation, remains uncertain. This pilot study assessed the accuracy of the plethysmographic variability index (PVI), (Radical-7 pulse co-oximeter, Masimo®, Irvine, CA, USA) in predicting fluid responsiveness in 25 patients who required noradrenaline infusion to maintain mean arterial pressure over 65 mmHg and were mechanically ventilated with a 'lung-protective' strategy, and whether administering a fluid bolus was associated with a change in PVI (Δ PVI). In this study, fluid responsiveness was defined as an increase in stroke volume of greater than 15% after a 500 ml bolus of colloid infusion over 20 minutes. Of the 25 patients included in the study, only 12 (48%) were considered fluid responders. As static haemodynamic parameters, PVI, central venous pressure and inferior vena cava distensibility index were all inaccurate at predicting volume responsiveness with PVI being the least accurate (area under the receiver operating characteristic curve=0.41, 95% confidence interval 0.18 to 0.65). However, fluid responsiveness was associated with a change in PVI, but not a change in heart rate or central venous pressure. This association between Δ PVI and fluid responsiveness may be a surrogate marker of improved cardiac output following a fluid bolus and warrants further investigation.
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Affiliation(s)
- A K Baker
- Department of Intensive Care Medicine, Royal Perth Hospital, Perth, Western Australia
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Gan H, Cannesson M, Chandler JR, Ansermino JM. Predicting Fluid Responsiveness in Children. Anesth Analg 2013; 117:1380-92. [PMID: 24257389 DOI: 10.1213/ane.0b013e3182a9557e] [Citation(s) in RCA: 155] [Impact Index Per Article: 14.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
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Abstract
Predicting fluid responsiveness, the response of stroke volume to fluid loading, is a relatively novel concept that aims to optimise circulation, and as such organ perfusion, while avoiding futile and potentially deleterious fluid administrations in critically ill patients. Dynamic parameters have shown to be superior in predicting the response to fluid loading compared with static cardiac filling pressures. However, in routine clinical practice the conditions necessary for dynamic parameters to predict fluid responsiveness are frequently not met. Passive leg raising as a means to alter biventricular preload in combination with subsequent measurement of the change in stroke volume can provide a fast and accurate way to guide fluid management in a broad population of critically ill patients.
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Hemodynamic instability and fluid responsiveness. Can J Anaesth 2013; 60:1240-7. [PMID: 24114743 DOI: 10.1007/s12630-013-0036-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/05/2013] [Accepted: 09/13/2013] [Indexed: 01/12/2023] Open
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Thiele RH, Colquhoun DA, Forkin KT, Durieux ME. Assessment of the agreement between photoplethysmographic and arterial waveform respiratory variation in patients undergoing spine surgery. J Med Eng Technol 2013; 37:409-415. [PMID: 23941460 DOI: 10.3109/03091902.2013.822027] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Respiratory variation in the arterial blood pressure and photoplethysmographic (PPG) waveforms have both been shown to predict the haemodynamic response to volume administration. Whether or not the two can be considered interchangeable is controversial. Twenty-three patients undergoing spine surgery received both a 20 gauge intra-arterial catheter and a Masimo adult adhesive SpHb sensor connected to a Radical-7 monitor. Pulse pressure variation (PPV) was calculated off-line at 1-min intervals. Pleth Variability Index (PVI) and Perfusion Index data were recorded. After exclusion of outliers, agreement between PPV and PVI was assessed using a repeated measures Bland-Altman approach. Concordance between changes in PPV and PVI was assessed using a four-quadrant plot with a 20% zone of exclusion. In total, 6549 min of data were collected. Repeated measures Bland-Altman analysis identified a bias of 2.2% and 95% confidence intervals of ±15.3% (limits of agreement -13.1 and +17.6%). The concordance rate between changes in PPV and changes in PVI was 51%. The agreement between respiratory variation in the arterial blood pressure and PPG waveforms is poor and these two should not be considered interchangeable. Changes in PPV are unrelated to changes in PVI. The data, combined with recently published work from other authors, suggests that the low frequency oscillations in the PPG waveform are not related to the low frequency oscillation in the systemic arterial blood pressure tracing and may be related to changes in venous pressure, peripheral tone or other physiologic phenomena yet to be described.
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Affiliation(s)
- Robert H Thiele
- Department of Anesthesiology, University of Virginia School of Medicine , Box 800710, Charlottesville, VA 22908-0710 , USA
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41
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Feissel M, Kalakhy R, Banwarth P, Badie J, Pavon A, Faller JP, Quenot JP. Plethysmographic variation index predicts fluid responsiveness in ventilated patients in the early phase of septic shock in the emergency department: a pilot study. J Crit Care 2013; 28:634-9. [PMID: 23683565 DOI: 10.1016/j.jcrc.2013.03.011] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/22/2012] [Revised: 03/12/2013] [Accepted: 03/14/2013] [Indexed: 11/19/2022]
Abstract
PURPOSE Feasibility study examining whether plethysmographic variability index (PVI) can predict fluid responsiveness in mechanically ventilated patients in the early phase of septic shock in the emergency department. MATERIALS AND METHODS Monocentric, prospective, observational study that included 31 mechanically ventilated and sedated patients with septic shock in whom volume expansion was planned. The patients were equipped with a pulse oximeter that automatically calculated and displayed PVI. The intervention consisted in infusing 8 mL/kg of hydroxylethyl starch over a 20-minute period. Before and after intervention, we recorded PVI and measured the aortic velocity-time integral (VTIao) using transthoracic echocardiography. Responders were defined as patients who increased their VTIao by 15% or higher after fluid infusion. RESULTS Sixteen patients were classified as responders, and 15 as nonresponders. Mean PVI values before intervention were significantly higher in responders vs nonresponders (30%±9% vs 8%±5%, P<.001). Plethysmographic variability index values before intervention were correlated with percent changes in VTIao induced by intervention (R2=0.67; P<.001). A PVI threshold value of 19% discriminates responders from nonresponders with a sensitivity of 94% and a specificity of 87% (area under the curve, 0.97; P<.001). CONCLUSION Our study suggests that PVI is a feasible and interesting method to predict fluid responsiveness in early phase septic shock patients in the emergency department.
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Affiliation(s)
- Marc Feissel
- Service de Réanimation, Maladies Infectieuses, Centre Hospitalier de Belfort-Montbéliard, Hôpital de Belfort, Belfort, France
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Kalantari K, Chang JN, Ronco C, Rosner MH. Assessment of intravascular volume status and volume responsiveness in critically ill patients. Kidney Int 2013; 83:1017-28. [PMID: 23302716 DOI: 10.1038/ki.2012.424] [Citation(s) in RCA: 65] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/19/2022]
Abstract
Accurate assessment of a patient's volume status, as well as whether they will respond to a fluid challenge with an increase in cardiac output, is a critical task in the care of critically ill patients. Despite this, most decisions regarding fluid therapy are made either empirically or with limited and poor data. Given recent data highlighting the negative impact of either inadequate or overaggressive fluid therapy, understanding the tools and techniques available for accurate volume assessment is critical. This review highlights both static and dynamic methods that can be utilized to help in the assessment of volume status.
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Affiliation(s)
- Kambiz Kalantari
- Division of Nephrology, University of Virginia Health System, Charlottesville, Virginia 22908, USA
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Giraud R, Siegenthaler N, Morel DR, Romand JA, Brochard L, Bendjelid K. Respiratory change in ECG-wave amplitude is a reliable parameter to estimate intravascular volume status. J Clin Monit Comput 2012; 27:107-11. [PMID: 23117586 DOI: 10.1007/s10877-012-9405-6] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2012] [Accepted: 10/12/2012] [Indexed: 11/30/2022]
Abstract
Electrocardiogram (ECG) is a standard type of monitoring in intensive care medicine. Several studies suggest that changes in ECG morphology may reflect changes in volume status. The "Brody effect", a theoretical analysis of left ventricular (LV) chamber size influence on QRS-wave amplitude, is the key element of this phenomenon. It is characterised by an increase in QRS-wave amplitude that is induced by an increase in ventricular preload. This study investigated the influence of changes in intravascular volume status on respiratory variations of QRS-wave amplitudes (ΔECG) compared with respiratory pulse pressure variations (ΔPP), considered as a reference standard. In 17 pigs, ECG and arterial pressure were recorded. QRS-wave amplitude was measured from the Biopac recording to ensure that in all animals ECG electrodes were always at the same location. Maximal QRS amplitude (ECGmax) and minimal QRS amplitude (ECGmin) were determined over one respiratory cycle. ΔECG was calculated as 100 × [(ECGmax - ECGmin)/(ECGmax + ECGmin)/2]. ΔECG and ΔPP were simultaneously recorded. Measurements were performed at different time points: during normovolemic conditions, after haemorrhage (25 mL/kg), and following re-transfusion (25 mL/kg) with constant tidal volume (10 mL/kg) and respiration rate (15 breath/min). At baseline, ΔPP and ΔECG were both <12 %. ΔPP were significantly correlated with ΔECG (r(2) = 0.89, p < 0.001). Volume loss induced by haemorrhage increased significantly ΔPP and ΔECG. Moreover, during this state, ΔPP were significantly correlated with ΔECG (r(2) = 0.86, p < 0.001). Re-transfusion significantly decreased ΔPP and ΔECG, and ΔPP were significantly correlated with ΔECG (r(2) = 0.90, p < 0.001). The observed correlations between ΔPP and ΔECG at each time point of the study suggest that ΔECG is a reliable parameter to estimate the changes in intravascular volume status and provide experimental confirmation of the "Brody effect."
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Affiliation(s)
- Raphaël Giraud
- Intensive Care Service, Geneva University Hospitals, 4 Rue Gabrielle Perret-Gentil, 1211, Geneva 14, Switzerland.
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Monnet X, Guérin L, Jozwiak M, Bataille A, Julien F, Richard C, Teboul JL. Pleth variability index is a weak predictor of fluid responsiveness in patients receiving norepinephrine. Br J Anaesth 2012; 110:207-13. [PMID: 23103777 DOI: 10.1093/bja/aes373] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
BACKGROUND In patients receiving an infusion of norepinephrine, the relationship between the amplitude of the oximeter plethysmographic waveform and stroke volume may be variable and quality of the waveform might be reduced, compared with patients not receiving norepinephrine. We assessed the reliability of the pleth variability index (PVI), an automatic measurement of the respiratory variation of the plethysmographic waveform, for predicting fluid responsiveness in patients receiving norepinephrine infusions. METHODS We measured the response of cardiac index (transpulmonary thermodilution) to i.v. fluid administration in 42 critically ill patients receiving norepinephrine. Patients with arrhythmias, spontaneous breathing, tidal volume <8 ml kg(-1), and respiratory system compliance <30 ml cm H(2)O(-1) were excluded. Before fluid administration, we recorded the arterial pulse pressure variation (PPV) and pulse contour analysis-derived stroke volume variation (SVV, PiCCO2) and PVI (Masimo Radical-7). RESULTS In seven patients, the plethysmographic signal could not be obtained. Among the 35 remaining patients [mean SAPS II score=77 (sd=17)], i.v. fluid increased cardiac index ≥15% in 15 'responders'. A baseline PVI ≥16% predicted fluid responsiveness with a sensitivity of 47 (inter-quartile range=21-73)% and a specificity of 90 (68-99)%. The area under the receiver operating characteristic curve was significantly lower for PVI [0.68 (0.09)] than for PPV and SVV [0.93 (0.06) and 0.89 (0.07), respectively]. Considering all pairs of measurements, PVI was correlated with PPV (r(2)=0.27). The fluid-induced changes in PVI and PPV were not significantly correlated. CONCLUSIONS PVI was less reliable than PPV and SVV for predicting fluid responsiveness in critically ill patients receiving norepinephrine. In addition, PVI could not be measured in a significant proportion of patients. This suggests that PVI is not useful in patients receiving norepinephrine.
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Affiliation(s)
- X Monnet
- Hôpitaux universitaires Paris-Sud, Hôpital de Bicêtre, service de réanimation médicale, 78, rue du Général Leclerc, Le Kremlin-Bicêtre F-94270, France.
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Abstract
The photoplethysmogram (PPG) is a noninvasive circulatory signal related to the pulsatile volume in tissue and is displayed by many pulse oximeters. The PPG is similar in appearance to the invasive arterial waveform, but is noninvasive and ubiquitous in hospitals. There is increasing interest in seeking circulatory information from the PPG and developing techniques for a wide variety of novel applications. This article addresses the basic physics of photoplethysmography, physiologic principles behind pulse oximetry operation, and recent technological advances in the usefulness of the PPG waveform to assess microcirculation and intravascular fluid volume monitoring during intensive care.
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Affiliation(s)
- Rakesh Sahni
- Division of Neonatal-Perinatal Medicine, Department of Pediatrics, College of Physicians and Surgeons, Columbia University, 3959 Broadway MSCHN 1201, New York, NY 10032-3702, USA.
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Optimization of preload in severe sepsis and septic shock. Crit Care Res Pract 2012; 2012:761051. [PMID: 22919473 PMCID: PMC3420225 DOI: 10.1155/2012/761051] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2012] [Accepted: 05/24/2012] [Indexed: 01/09/2023] Open
Abstract
In sepsis both under- and overresuscitation are associated with increased morbidity and mortality. Moreover, sepsis can be complicated by myocardial dysfunction, and only half of the critically ill patients exhibit preload responsiveness. It is of paramount importance to accurately, safely, and rapidly determine and optimize preload during resuscitation. Traditional methods of determining preload based on measurement of pressure in a heart chamber or volume of a heart chamber ("static" parameters) are inaccurate and should be abandoned in favor of determining preload responsiveness by using one of the "dynamic parameters" based on respiratory variation in the venous or arterial circulation or based on change in stroke volume in response to an endogenous or exogenous volume challenge. The recent development and validation of a number of noninvasive technologies now allow us to optimize preload in an accurate, safe, rapid and, cost-effective manner.
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Accuracy of plethysmographic indices as predictors of fluid responsiveness in mechanically ventilated adults: a systematic review and meta-analysis. Intensive Care Med 2012; 38:1429-37. [DOI: 10.1007/s00134-012-2621-1] [Citation(s) in RCA: 66] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2012] [Accepted: 05/29/2012] [Indexed: 10/28/2022]
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Prediction of fluid responsiveness in septic shock patients: comparing stroke volume variation by FloTrac/Vigileo and automated pulse pressure variation. Eur J Anaesthesiol 2012; 29:64-9. [PMID: 21946822 DOI: 10.1097/eja.0b013e32834b7d82] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
OBJECTIVES The aim of this study was to assess and compare the ability of the automatically and continuously measured stroke volume variation (SVV) obtained by FloTrac/Vigileo, and pulse pressure variation (PPV) measured by an IntelliVue MP monitor, to predict fluid responsiveness in mechanically ventilated septic shock patients. METHOD We conducted a prospective study on 42 septic shock patients. SVV, PPV and other haemodynamic data were recorded before and after fluid administration of 500 ml of 6% hydroxyethyl starch. Responders were defined as patients with an increase in stroke volume index of at least 15% after fluid loading. RESULTS Twenty-four (57.1%) patients were classified as fluid responders. The baseline SVV correlated with the baseline PPV (r=0.96, P<0.001). SVV and PPV were significantly higher in responders than in nonresponders (15.5±4.5 vs. 8.2±3.3% and 16.4±5.2 vs. 8.3±3.5, respectively, P<0.001 for both). There was no difference between the area under the receiver operating characteristic curves of SVV [0.92, 95% confidence interval 0.832-1.00] and PPV (0.916, 95% confidence interval 0.829-1.00). The optimal threshold values in predicting fluid responsiveness were 10% for SVV (sensitivity 91.7% and specificity 83.3%) and 12% for PPV (sensitivity 83.3% and specificity 83.3%). Our results were independent of the site of arterial catheterisation. CONCLUSION The SVV, obtained by FloTrac/Vigileo, and the automated PPV, obtained by the IntelliVue MP monitor, showed comparable performance in terms of predicting fluid responsiveness in passively ventilated septic shock patients, with a regular cardiac rhythm and a tidal volume not less than 8 ml kg(-1).
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Moitra VK, Gabrielli A, Maccioli GA, O’Connor MF. Anesthesia advanced circulatory life support. Can J Anaesth 2012; 59:586-603. [PMID: 22528163 PMCID: PMC3345112 DOI: 10.1007/s12630-012-9699-3] [Citation(s) in RCA: 46] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2011] [Accepted: 03/14/2012] [Indexed: 02/07/2023] Open
Abstract
PURPOSE The constellation of advanced cardiac life support (ACLS) events, such as gas embolism, local anesthetic overdose, and spinal bradycardia, in the perioperative setting differs from events in the pre-hospital arena. As a result, modification of traditional ACLS protocols allows for more specific etiology-based resuscitation. PRINCIPAL FINDINGS Perioperative arrests are both uncommon and heterogeneous and have not been described or studied to the same extent as cardiac arrest in the community. These crises are usually witnessed, frequently anticipated, and involve a rescuer physician with knowledge of the patient's comorbidities and coexisting anesthetic or surgically related pathophysiology. When the health care provider identifies the probable cause of arrest, the practitioner has the ability to initiate medical management rapidly. CONCLUSIONS Recommendations for management must be predicated on expert opinion and physiological understanding rather than on the standards currently being used in the generation of ACLS protocols in the community. Adapting ACLS algorithms and considering the differential diagnoses of these perioperative events may prevent cardiac arrest.
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Affiliation(s)
- Vivek K. Moitra
- Department of Anesthesiology, College of Physicians and Surgeons, Columbia University, New York, NY USA
| | - Andrea Gabrielli
- Anesthesia Department, University of Florida, Gainesville, FL USA
| | | | - Michael F. O’Connor
- Department of Anesthesia and Critical Care, University of Chicago, 5841 S Maryland Ave, MC 4028, Chicago, IL 60637 USA
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Cannesson M, de Backer D, Hofer CK. Using arterial pressure waveform analysis for the assessment of fluid responsiveness. Expert Rev Med Devices 2012; 8:635-46. [PMID: 22026628 DOI: 10.1586/erd.11.30] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/12/2023]
Abstract
Predicting the effects of volume expansion on cardiac output and oxygen delivery is of major importance in different clinical scenarios. Functional hemodynamic parameters based on pulse waveform analysis, which are relying on the effects of mechanical ventilation on stroke volume and its surrogates, have been shown to be reliable predictors of fluid responsiveness during anesthesia and intensive care unit treatment, as demonstrated by several clinical studies and meta-analyses. However, different limitations of these parameters have to be considered when they are used in clinical practice. Today, they can be continuously and automatically monitored by a variety of commercially available devices. These parameters have been introduced into the concept of perioperative fluid management and hemodynamic optimization - an approach that may positively impact postoperative patients' outcomes. In this article, technical aspects of the assessment of the functional hemodynamic parameters derived from pulse waveform analysis are summarized, emphasizing their advantages, limitations and potential applications, primarily in a perioperative setting in order to improve patient outcome.
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Affiliation(s)
- Maxime Cannesson
- Department of Anesthesiology & Perioperative Care, School of Medicine, University of California, Irvine, CA, USA.
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