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Tiruvoipati R, Ludski J, Gupta S, Subramaniam A, Ponnapa Reddy M, Paul E, Haji K. Evaluation of the safety and efficacy of extracorporeal carbon dioxide removal in the critically ill using the PrismaLung+ device. Eur J Med Res 2023; 28:291. [PMID: 37596670 PMCID: PMC10436516 DOI: 10.1186/s40001-023-01269-2] [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: 06/02/2023] [Accepted: 08/05/2023] [Indexed: 08/20/2023] Open
Abstract
BACKGROUND Several extracorporeal carbon dioxide removal (ECCO2R) devices are currently in use with variable efficacy and safety profiles. PrismaLung+ is an ECCO2R device that was recently introduced into clinical practice. It is a minimally invasive, low flow device that provides partial respiratory support with or without renal replacement therapy. Our aim was to describe the clinical characteristics, efficacy, and safety of PrismaLung+ in patients with acute hypercapnic respiratory failure. METHODS All adult patients who required ECCO2R with PrismaLung+ for hypercapnic respiratory failure in our intensive care unit (ICU) during a 6-month period between March and September 2022 were included. RESULTS Ten patients were included. The median age was 55.5 (IQR 41-68) years, with 8 (80%) male patients. Six patients had acute respiratory distress syndrome (ARDS), and two patients each had exacerbations of asthma and chronic obstructive pulmonary disease (COPD). All patients were receiving invasive mechanical ventilation at the time of initiation of ECCO2R. The median duration of ECCO2R was 71 h (IQR 57-219). A significant improvement in pH and PaCO2 was noted within 30 min of initiation of ECCO2R. Nine patients (90%) survived to weaning of ECCO2R, eight (80%) survived to ICU discharge and seven (70%) survived to hospital discharge. The median duration of ICU and hospital stays were 14.5 (IQR 8-30) and 17 (IQR 11-38) days, respectively. There were no patient-related complications with the use of ECCO2R. A total of 18 circuits were used in ten patients (median 2 per patient; IQR 1-2). Circuit thrombosis was noted in five circuits (28%) prior to reaching the expected circuit life with no adverse clinical consequences. CONCLUSION(S) PrismaLung+ rapidly improved PaCO2 and pH with a good clinical safety profile. Circuit thrombosis was the only complication. This data provides insight into the safety and efficacy of PrismaLung+ that could be useful for centres aspiring to introduce ECCO2R into their clinical practice.
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Affiliation(s)
- Ravindranath Tiruvoipati
- Department of Intensive Care Medicine, Frankston Hospital, Peninsula Health, Frankston, VIC, 3199, Australia.
- Division of Medicine, Peninsula Clinical School, Monash University, Frankston, VIC, Australia.
- ANZIC-RC, School of Public Health and Preventive Medicine, Monash University, 553 St Kilda Road, Melbourne, VIC, 3004, Australia.
| | - Jarryd Ludski
- Department of Intensive Care Medicine, Frankston Hospital, Peninsula Health, Frankston, VIC, 3199, Australia
| | - Sachin Gupta
- Department of Intensive Care Medicine, Frankston Hospital, Peninsula Health, Frankston, VIC, 3199, Australia
- Division of Medicine, Peninsula Clinical School, Monash University, Frankston, VIC, Australia
| | - Ashwin Subramaniam
- Department of Intensive Care Medicine, Frankston Hospital, Peninsula Health, Frankston, VIC, 3199, Australia
- Division of Medicine, Peninsula Clinical School, Monash University, Frankston, VIC, Australia
- ANZIC-RC, School of Public Health and Preventive Medicine, Monash University, 553 St Kilda Road, Melbourne, VIC, 3004, Australia
- Department of Intensive Care Medicine, Dandenong Hospital, Dandenong, Australia
| | - Mallikarjuna Ponnapa Reddy
- Department of Intensive Care Medicine, Frankston Hospital, Peninsula Health, Frankston, VIC, 3199, Australia
- Division of Medicine, Peninsula Clinical School, Monash University, Frankston, VIC, Australia
- Department of Intensive Care, Calvary Hospital, Canberra, ACT, Australia
| | - Eldho Paul
- ANZIC-RC, School of Public Health and Preventive Medicine, Monash University, 553 St Kilda Road, Melbourne, VIC, 3004, Australia
- Alfred Hospital, Melbourne, VIC, Australia
| | - Kavi Haji
- Department of Intensive Care Medicine, Frankston Hospital, Peninsula Health, Frankston, VIC, 3199, Australia
- Division of Medicine, Peninsula Clinical School, Monash University, Frankston, VIC, Australia
- Department of Surgery, University of Melbourne, Melbourne, VIC, Australia
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Kapoor PM, Oza P, Goyal V, Mehta Y, Kanchi M. Extracorporeal Membrane Oxygenation Carbon Dioxide Removal. JOURNAL OF CARDIAC CRITICAL CARE TSS 2023. [DOI: 10.25259/mm_jccc_304] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/31/2023] Open
Abstract
Protective lung ventilation is the mainstay ventilation strategy for patients on extracorporeal membrane oxygenation (ECMO), as prolonged mechanical ventilation increases morbidity and mortality; the technicalities of ventilation with ECMO have evolved in the last decade. ECMO on the other end of the spectrum is a complete or total extracorporeal support, which supplies complete physiological blood gas exchanges, normally performed by the native lungs and thus is capable of delivering oxygen (O2) and removing CO equal to the metabolic needs of the patient, it requires higher flows, is more complex, and uses bigger cannulas, higher dose of heparin and higher blood volume for priming. This review describes in detail carbon dioxide removal on ECMO.
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Affiliation(s)
| | - Pranay Oza
- Department of ECMO, RVCC, Mumbai, Maharashtra, India,
| | - Venkat Goyal
- Department of ECMO, RVCC, Mumbai, Maharashtra, India,
| | - Yatin Mehta
- Department of ECMO, RVCC, Mumbai, Maharashtra, India,
| | - Muralidhar Kanchi
- Department of Anesthesia and Intensive Care, Narayana Institute of Cardiac Sciences, Narayana Health City, Bommasandra, Karnataka, India,
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Key Role of Respiratory Quotient to Reduce the Occurrence of Hypoxemia During Extracorporeal Gas Exchange: A Theoretical Analysis. Crit Care Med 2021; 48:e1327-e1331. [PMID: 33031149 DOI: 10.1097/ccm.0000000000004619] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVES Extracorporeal respiratory support, including low blood flow systems providing mainly extracorporeal CO2 removal, are increasingly applied in clinical practice. Gas exchange physiology during extracorporeal respiratory support is complex and differs between full extracorporeal membrane oxygenation and extracorporeal CO2 removal. Aim of the present article is to review pathophysiological aspects which are relevant for the understanding of hypoxemia development during extracorporeal CO2 removal. We will describe the mathematical and physiologic background underlying changes in respiratory quotient and alveolar oxygen tension during venovenous extracorporeal gas exchange and highlight the clinical implications. DESIGN Theoretical analysis of venovenous extracorporeal gas exchange. SETTING Italian university research hospital. PATIENTS None. INTERVENTIONS None. MEASUREMENTS AND MAIN RESULTS While the effect of extracorporeal CO2 removal on the respiratory quotient of the native lung has long been known, the role of extracorporeal oxygenation in dictating changes in the respiratory quotient has been less addressed. Indeed, both extracorporeal CO2 removal and extracorporeal oxygen delivery affect the respiratory quotient of the native lung and thus influence the alveolar PO2. Indeed, for the same amount of extracorporeal CO2 extraction, it is possible to reduce the FIO2, reduce the risk of absorption atelectasis, and maintain the same alveolar PO2, by increasing the extracorporeal oxygen delivery. CONCLUSIONS Worsening of hypoxemia is frequent during low-flow extracorporeal CO2 removal combined with ultraprotective mechanical ventilation. In this context, increasing extracorporeal oxygen delivery, increases the respiratory quotient of the native lung and could reduce both the occurrence of alveolar hypoxia and absorption atelectasis, thus optimizing the residual lung function.
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Extracorporeal Carbon Dioxide Removal: From Bench to Bedside and Back. Crit Care Med 2020; 48:1924-1925. [PMID: 33255119 DOI: 10.1097/ccm.0000000000004646] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Staudinger T. Update on extracorporeal carbon dioxide removal: a comprehensive review on principles, indications, efficiency, and complications. Perfusion 2020; 35:492-508. [PMID: 32156179 DOI: 10.1177/0267659120906048] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
TECHNOLOGY Extracorporeal carbon dioxide removal means the removal of carbon dioxide from the blood across a gas exchange membrane without substantially improving oxygenation. Carbon dioxide removal is possible with substantially less extracorporeal blood flow than needed for oxygenation. Techniques for extracorporeal carbon dioxide removal include (1) pumpless arterio-venous circuits, (2) low-flow venovenous circuits based on the technology of continuous renal replacement therapy, and (3) venovenous circuits based on extracorporeal membrane oxygenation technology. INDICATIONS Extracorporeal carbon dioxide removal has been shown to enable more protective ventilation in acute respiratory distress syndrome patients, even beyond the so-called "protective" level. Although experimental data suggest a benefit on ventilator induced lung injury, no hard clinical evidence with respect to improved outcome exists. In addition, extracorporeal carbon dioxide removal is a tool to avoid intubation and mechanical ventilation in patients with acute exacerbated chronic obstructive pulmonary disease failing non-invasive ventilation. This concept has been shown to be effective in 56-90% of patients. Extracorporeal carbon dioxide removal has also been used in ventilated patients with hypercapnic respiratory failure to correct acidosis, unload respiratory muscle burden, and facilitate weaning. In patients suffering from terminal fibrosis awaiting lung transplantation, extracorporeal carbon dioxide removal is able to correct acidosis and enable spontaneous breathing during bridging. Keeping these patients awake, ambulatory, and breathing spontaneously is associated with favorable outcome. COMPLICATIONS Complications of extracorporeal carbon dioxide removal are mostly associated with vascular access and deranged hemostasis leading to bleeding. Although the spectrum of complications may differ, no technology offers advantages with respect to rate and severity of complications. So called "high-extraction systems" working with higher blood flows and larger membranes may be more effective with respect to clinical goals.
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Affiliation(s)
- Thomas Staudinger
- Department of Medicine I, Intensive Care Unit, Medical University of Vienna, Vienna General Hospital, Vienna, Austria
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Patel AR, Patel AR, Singh S, Singh S, Khawaja I. Applied Uses of Extracorporeal Membrane Oxygenation Therapy. Cureus 2019; 11:e5163. [PMID: 31341752 PMCID: PMC6639062 DOI: 10.7759/cureus.5163] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/13/2022] Open
Abstract
Extracorporeal membrane oxygenation (ECMO) therapy has been around since the 1970s and has completely changed how critical care physicians view supportive therapy for certain patients. ECMO therapy is a supportive therapy provided by a mechanical extracorporeal circuit that is able to directly oxygenate and remove carbon dioxide from the blood. By performing this, ECMO can provide cardiac, respiratory, or combined cardiopulmonary supportive therapy in cases of failure. ECMO therapy also places less emphasis on invasive mechanical ventilation, which prevents barotrauma and gives rest to the lungs. Therefore, they are used for several different conditions. This review article focuses on the definition, principles, types, and practical applications of ECMO therapy.
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Affiliation(s)
- Avani R Patel
- Internal Medicine, Northern California Kaiser Permanente, Fremont, USA
| | - Amar R Patel
- Internal Medicine, Northern California Kaiser Permanente, Fremont, USA
| | - Shivank Singh
- Internal Medicine, Southern Medical University, Guangzhou, CHN
| | - Shantanu Singh
- Pulmonary Medicine, Marshall University School of Medicine, Huntington, USA
| | - Imran Khawaja
- Pulmonary Medicine, Marshall University School of Medicine, Huntington, USA
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Takahashi N, Nakada TA, Oda S. Efficient CO 2 removal using extracorporeal lung and renal assist device. J Artif Organs 2018; 21:427-434. [PMID: 29980955 DOI: 10.1007/s10047-018-1058-x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2018] [Accepted: 06/25/2018] [Indexed: 12/01/2022]
Abstract
We developed a novel system comprising acid infusion, membrane lung, and a continuous renal replacement therapy console for efficient CO2 removal at a low blood flow. To evaluate the new system, we used an ex vivo experimental model using swine blood. A liter of aliquoted blood adjusted to pH 7.25 and pCO2 65 mm Hg was mixed with acid (0, 10, or 20 mL of lactic or hydrochloric acid [1 mol/L]) and was immediately delivered to the system in a single pass. We collected blood samples at each point of the circuit and calculated the amount of CO2 eliminated by the membrane lung. The new system removed 13.2 ± 0.8, 32.0 ± 2.1, and 51.6 ± 3.7 mL/min of CO2 (with 0, 10, and 20 mEq/L of lactic acid) and 21.2 ± 1.2, 27.3 ± 0.3, and 42.0 ± 1.3 mL/min (with 0, 10, and 20 mEq/L of hydrochloric acid), respectively. The levels of lactate and Cl- ions for acid-base equilibrium were restored after continuous hemodiafiltration. Thus, the amount of CO2 eliminated by the membrane lung was 3.9 times higher with lactic acid and 2.0 times higher with hydrochloric acid compared with non-acid controls. In conclusion, this easy-to-setup CO2 removal system was safe, effective, and removed CO2 at a low blood flow.
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Affiliation(s)
- Nozomi Takahashi
- Department of Emergency and Critical Care Medicine, Chiba University Graduate School of Medicine, 1-8-1 Inohana, Chuo, Chiba, 260-8677, Japan
| | - Taka-Aki Nakada
- Department of Emergency and Critical Care Medicine, Chiba University Graduate School of Medicine, 1-8-1 Inohana, Chuo, Chiba, 260-8677, Japan.
| | - Shigeto Oda
- Department of Emergency and Critical Care Medicine, Chiba University Graduate School of Medicine, 1-8-1 Inohana, Chuo, Chiba, 260-8677, Japan
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Affiliation(s)
- J E Lynch
- Department of Critical Care Nursing, The University of Texas Medical Branch, 301 University Boulevard, Galveston, TX 77551-0528, USA
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Large Animal Model of Pumpless Arteriovenous Extracorporeal CO₂ Removal Using Room Air via Subclavian Vessels. ASAIO J 2016; 62:110-3. [PMID: 26461241 DOI: 10.1097/mat.0000000000000291] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
Abstract
End-stage lung disease (ESLD) causes progressive hypercapnia and dyspnea and impacts quality of life. Many extracorporeal support (ECS) configurations for CO2 removal resolve symptoms but limit ambulation. An ovine model of pumpless ECS using subclavian vessels was developed to allow for ambulatory support. Vascular grafts were anastomosed to the left subclavian vessels in four healthy sheep. A low-resistance membrane oxygenator was attached in an arteriovenous (AV) configuration. Device function was evaluated in each animal while awake and spontaneously breathing and while mechanically ventilated with hypercapnia induced. Sweep gas (FiO2 = 0.21) to the device was increased from 0 to 15 L/min, and arterial and postdevice blood gases, as well as postdevice air, were sampled. Hemodynamics remained stable with average AV shunt flows of 1.34 ± 0.14 L/min. In awake animals, CO2 removal was 3.4 ± 1.0 ml/kg/min at maximum sweep gas flow. Respiratory rate decreased from 60 ± 25 at baseline to 30 ± 11 breaths per minute. In animals with induced hypercapnia, PaCO2 increased to 73.9 ± 15.1. At maximum sweep gas flow, CO2 removal was 3.4 ± 0.4 ml/kg/min and PaCO2 decreased to 49.1 ± 6.7 mm Hg. Subclavian AV access is effective in lowering PaCO2 and respiratory rate and is potentially an effective ambulatory destination therapy for ESLD patients.
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Zhou X, Loran DB, Wang D, Hyde BR, Lick SD, Zwischenberger JB. Seventy-two hour gas exchange performance and hemodynamic properties of NOVALUNG®iLA as a gas exchanger for arteriovenous carbon dioxide removal. Perfusion 2016; 20:303-8. [PMID: 16363314 DOI: 10.1191/0267659105pf838oa] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
Objective: Acute respiratory failure is complicated by acidosis and altered end-organ perfusion. NOVA-LUNG®iLA is an interventional lung assist (ILA) device for arteriovenous carbon dioxide removal (AVCO2R). The present study was conducted to evaluate the device for short-term CO2 removal performance and hemodynamic response. Methods: Six adult sheep received cannulation of the jugular vein and carotid artery. The ILA-AVCO2R circuit was placed on the sheep for 72 hours. Hemodynamics and PaCO2 were measured; CO2 removal was calculated while varying sweep gas flow rates (Qg), device blood flow rates (Qb), and PaCO2. Results: Hemo-dynamic variables remained normal throughout the 72 hour study. CO2 removal increased with increases in Qgor Qb. Mean CO2 removal was 119.3 ml/min for Qb 1L/min, Qg 5 L/min, and PaCO2 40 - 50 mmHg.PaCO2 was directly proportional to CO2 clearance (R-0.72, p B/0.001). Conclusion: NOVALUNG®iLA can provide near total CO2 removal with Qb 1 - 2 L/min,Qg 5 L/min, and minimal flow resistance (3.889/0.82 mmHg/L/min). PaCO2 correlates with CO2 removal and is dependent on Qb and Qg.
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Affiliation(s)
- Xiaoqin Zhou
- Department of Surgery, The University of Texas Medical Branch, Galveston, Texas 77551-0528, USA
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Sharma AS, Weerwind PW, Bekers O, Wouters EM, Maessen JG. Carbon dioxide dialysis in a swine model utilizing systemic and regional anticoagulation. Intensive Care Med Exp 2016; 4:2. [PMID: 26780677 PMCID: PMC4715831 DOI: 10.1186/s40635-016-0076-3] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/23/2015] [Accepted: 01/08/2016] [Indexed: 11/13/2022] Open
Abstract
Background Extracorporeal carbon dioxide removal (ECCO2R) has been gaining interest to potentially facilitate gas transfer and equilibrate mild to moderate hypercapnic acidosis, when standard therapy with non-invasive ventilation is deemed refractory. However, concern regarding the effectiveness of low-flow CO2 removal remains. Additionally, the prospect to steadily reduce hypercapnia via low-flow ECCO2R technique is limited, especially with regional anticoagulation which potentially reduces the risk of bleeding. Therefore, an in vivo study was conducted to determine the efficacy of CO2 removal through a modified renal dialysis unit during the carbon dioxide dialysis study using systemic and regional anticoagulation. Methods The acute study was conducted for 14 h in landrace pigs (51 ± 3 kg). CO2 removal using a diffusion membrane oxygenator substituting the hemoconcentrator was provided for 6 h. Blood and gas (100 % O2) flows were set at 200 and 5 L/min, respectively. Anticoagulation was achieved by systemic heparinization (n = 7) or regional trisodium citrate 4 % (n = 7). Results The CO2 transfer was highest during the initial hour and ranged from 45 to 35 mL/min, achieving near eucapnic values. Regional and systemic anticoagulation were both effective in decreasing arterial pCO2 (from 8.9 ± 1.3 kPa to 5.6 ± 0.8 kPa and from 8.6 ± 1.0 kPa to 6.3 ± 0.7 kPa, p < 0.05 for both groups, respectively). Furthermore, pH improved (from 7.32 ± 0.08 to 7.47 ± 0.07 and from 7.37 ± 0.04 to 7.49 ± 0.01, p < 0.05) for both regional and systemic anticoagulation groups, respectively. Upon ceasing CO2 dialysis, hypercapnia ensued. The liver and kidney function test results were normal, and scanning electron microscopy analysis revealed only some cellular and fibrin adhesion on the oxygenator fibre in the heparin group. Conclusions CO2 dialysis utilizing either regional or systemic anticoagulation showed to be safe and effective in steady transfer of CO2 and consequently optimizing pH.
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Affiliation(s)
- A S Sharma
- Department of Cardiothoracic Surgery, CARIM, Maastricht University Medical Center, PO box 5800, 6202 AZ, Maastricht, the Netherlands.
| | - P W Weerwind
- Department of Cardiothoracic Surgery, CARIM, Maastricht University Medical Center, PO box 5800, 6202 AZ, Maastricht, the Netherlands
| | - O Bekers
- Department of Clinical Chemistry, Maastricht University Medical Center, Maastricht, the Netherlands
| | - E M Wouters
- Department of Respiratory Medicine, NUTRIM, Maastricht University Medical Center, Maastricht, the Netherlands
| | - J G Maessen
- Department of Cardiothoracic Surgery, CARIM, Maastricht University Medical Center, PO box 5800, 6202 AZ, Maastricht, the Netherlands
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Percutaneous cannulation for extracorporeal membrane oxygenation by intensivists: a retrospective single-institution case series. Crit Care Med 2015; 43:1010-5. [PMID: 25746749 DOI: 10.1097/ccm.0000000000000883] [Citation(s) in RCA: 72] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
OBJECTIVE Extracorporeal membrane oxygenation provides support for patients with severe acute cardiopulmonary failure, allowing the application of lung or myocardial rest in anticipation of organ recovery, or as a bridge to long-term support. Advances in technology have improved the safety and ease of application of extracorporeal membrane oxygenation. Percutaneous cannulation is one of these advances and is now preferred over surgical cannulation in most cases. Percutaneous cannulation is increasingly performed by intensivists, cardiologists, interventional radiologists, and related specialties. The objective of this study is to review the experience of percutaneous cannulation by intensivists at a single institution. DESIGN A retrospective review of 100 subjects undergoing percutaneous cannulation for extracorporeal membrane oxygenation. SETTING Adult ICUs and PICUs at a tertiary academic medical institution. PATIENTS Critically ill neonatal, pediatric, and adult subjects with severe respiratory and/or cardiac failure undergoing percutaneous cannulation for extracorporeal membrane oxygenation. Modes of support included venoarterial, venovenous, venovenoarterial, and arteriovenous. INTERVENTIONS Percutaneous extracorporeal membrane oxygenation. MEASUREMENTS AND MAIN RESULTS Case reports submitted to the Extracorporeal Life Support Organization and hospital records of the subjects were retrospectively reviewed. Subject demographics, type of support, cannulation configuration, types of cannulas, use of imaging modalities, and complications were recorded and summarized. One hundred ninety cannulations with cannula sizes from size 12 to 31F were performed by four intensivists in 100 subjects. Twenty-three were arterial (12-16F) and 167 were venous (12-31F). Preinsertion ultrasound was performed in 93 subjects (93%), fluoroscopic guidance in 79 subjects (85% of nonarteriovenous subjects), and ultrasound-guided insertion was performed in 65 subjects (65%). Two major complications occurred, each associated with mortality. Cannulation was successful in all other subjects (98% of subjects and 99% of cannulations). There were no cases of cannula-related bloodstream infection. CONCLUSIONS Percutaneous cannulation for extracorporeal membrane oxygenation by intensivists can be performed with a high rate of success and a low rate of complications when accompanied by imaging support.
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Schmidt M, Hodgson C, Combes A. Extracorporeal gas exchange for acute respiratory failure in adult patients: a systematic review. CRITICAL CARE : THE OFFICIAL JOURNAL OF THE CRITICAL CARE FORUM 2015; 19:99. [PMID: 25887146 PMCID: PMC4484573 DOI: 10.1186/s13054-015-0806-z] [Citation(s) in RCA: 52] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
This article is one of ten reviews selected from the Annual Update in Intensive Care and Emergency Medicine 2015 and co-published as a series in Critical Care. Other articles in the series can be found online at http://ccforum.com/series/annualupdate2015. Further information about the Annual Update in Intensive Care and Emergency Medicine is available from http://www.springer.com/series/8901.
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Affiliation(s)
- Matthieu Schmidt
- Université Pierre et Marie Curie, Medical-Surgical Intensive Care Unit, iCAN, Institute of Cardiometabolism and Nutrition, Hôpital de la Pitié-Salpêtrière, Assistance Publique-Hôpitaux de Paris, Paris, France.
| | - Carol Hodgson
- The Australian & New Zealand Intensive Care Research Centre and the Intensive Care Department, Alfred Hospital, Melbourne, Australia.
| | - Alain Combes
- Université Pierre et Marie Curie, Medical-Surgical Intensive Care Unit, iCAN, Institute of Cardiometabolism and Nutrition, Hôpital de la Pitié-Salpêtrière, Assistance Publique-Hôpitaux de Paris, Paris, France.
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What's new in extracorporeal carbon dioxide removal for COPD? Intensive Care Med 2015; 41:906-8. [PMID: 25643904 DOI: 10.1007/s00134-015-3677-5] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/26/2014] [Accepted: 01/20/2015] [Indexed: 10/24/2022]
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Techniques d’assistance respiratoire veinoveineuses et alternatives au cours du syndrome de détresse respiratoire aiguë. MEDECINE INTENSIVE REANIMATION 2013. [DOI: 10.1007/s13546-014-0873-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Kimmel JD, Arazawa DT, Ye SH, Shankarraman V, Wagner WR, Federspiel WJ. Carbonic anhydrase immobilized on hollow fiber membranes using glutaraldehyde activated chitosan for artificial lung applications. JOURNAL OF MATERIALS SCIENCE. MATERIALS IN MEDICINE 2013; 24:2611-21. [PMID: 23888352 PMCID: PMC3826877 DOI: 10.1007/s10856-013-5006-2] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2012] [Accepted: 07/15/2013] [Indexed: 05/11/2023]
Abstract
Extracorporeal CO2 removal from circulating blood is a promising therapeutic modality for the treatment of acute respiratory failure. The enzyme carbonic anhydrase accelerates CO2 removal within gas exchange devices by locally catalyzing HCO3 (-) into gaseous CO2 within the blood. In this work, we covalently immobilized carbonic anhydrase on the surface of polypropylene hollow fiber membranes using glutaraldehyde activated chitosan tethering to amplify the density of reactive amine functional groups for enzyme immobilization. XPS and a colorimetric amine assay confirmed higher amine densities on the chitosan coated fiber compared to control fiber. Chitosan/CA coated fibers exhibited accelerated CO2 removal in scaled-down gas exchange devices in buffer and blood (115% enhancement vs. control, 37% enhancement vs. control, respectively). Carbonic anhydrase immobilized directly on hollow fiber membranes without chitosan tethering resulted in no enhancement in CO2 removal. Additionally, fibers coated with chitosan/carbonic anhydrase demonstrated reduced platelet adhesion when exposed to blood compared to control and heparin coated fibers.
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Affiliation(s)
- J. D. Kimmel
- McGowan Institute for Regenerative Medicine, University of Pittsburgh, 3025 East Carson Street, Pittsburgh, PA 15203, USA. Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA, USA
| | - D. T. Arazawa
- McGowan Institute for Regenerative Medicine, University of Pittsburgh, 3025 East Carson Street, Pittsburgh, PA 15203, USA. Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA, USA
| | - S.-H. Ye
- McGowan Institute for Regenerative Medicine, University of Pittsburgh, 3025 East Carson Street, Pittsburgh, PA 15203, USA. Department of Surgery, University of Pittsburgh Medical Center, Pittsburgh, PA, USA
| | - V. Shankarraman
- McGowan Institute for Regenerative Medicine, University of Pittsburgh, 3025 East Carson Street, Pittsburgh, PA 15203, USA. Department of Surgery, University of Pittsburgh Medical Center, Pittsburgh, PA, USA
| | - W. R. Wagner
- McGowan Institute for Regenerative Medicine, University of Pittsburgh, 3025 East Carson Street, Pittsburgh, PA 15203, USA. Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA, USA. Department of Surgery, University of Pittsburgh Medical Center, Pittsburgh, PA, USA. Department of Chemical and Petroleum Engineering, University of Pittsburgh, Pittsburgh, PA, USA
| | - W. J. Federspiel
- McGowan Institute for Regenerative Medicine, University of Pittsburgh, 3025 East Carson Street, Pittsburgh, PA 15203, USA. Department of Bioengineering, University of Pittsburgh, Pittsburgh, PA, USA. Department of Chemical and Petroleum Engineering, University of Pittsburgh, Pittsburgh, PA, USA. Department of Critical Care Medicine, University of Pittsburgh Medical Center, Pittsburgh, PA, USA
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Yalındağ-Öztürk N, Vuran C, Karakoç F, Ersu R. Use of pumpless extracorporeal lung assist as rescue therapy in adolescent with cystic fibrosis. Pediatr Int 2013; 55:e83-5. [PMID: 23910813 DOI: 10.1111/ped.12129] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/30/2011] [Revised: 12/07/2011] [Accepted: 02/08/2013] [Indexed: 11/28/2022]
Abstract
There is abundant evidence that artificial ventilation can aggravate pre-existing lung disease, which may contribute to morbidity and mortality. This is especially true for patients with air leakages. This case report describes the use of a pumpless extracorporeal lung assist as a rescue therapy to provide time to heal during the mechanical ventilation of a 16-year-old with cystic fibrosis who could not be managed via conventional means.
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Affiliation(s)
- Nilüfer Yalındağ-Öztürk
- Division of Pediatric Critical Care, Department of Pediatrics, Başkent University Medical Research and Treatment Center in Istanbul, Turkey.
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Amoako KA, Montoya PJ, Major TC, Suhaib AB, Handa H, Brant DO, Meyerhoff ME, Bartlett RH, Cook KE. Fabrication and in vivo thrombogenicity testing of nitric oxide generating artificial lungs. J Biomed Mater Res A 2013; 101:3511-9. [PMID: 23613156 DOI: 10.1002/jbm.a.34655] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2012] [Revised: 01/16/2013] [Accepted: 02/04/2013] [Indexed: 12/19/2022]
Abstract
Hollow fiber artificial lungs are increasingly being used for long-term applications. However, clot formation limits their use to 1-2 weeks. This study investigated the effect of nitric oxide generating (NOgen) hollow fibers on artificial lung thrombogenicity. Silicone hollow fibers were fabricated to incorporate 50 nm copper particles as a catalyst for NO generation from the blood. Fibers with and without (control) these particles were incorporated into artificial lungs with a 0.1 m(2) surface area and inserted in circuits coated tip-to-tip with the NOgen material. Circuits (N = 5/each) were attached to rabbits in a pumpless, arterio-venous configuration and run for 4 h at an activated clotting time of 350-400 s. Three control circuits clotted completely, while none of the NOgen circuits failed. Accordingly, blood flows were significantly higher in the NOgen group (95.9 ± 11.7, p < 0.01) compared to the controls (35.2 ± 19.7; mL/min), and resistance was significantly higher in the control group after 4 h (15.38 ± 9.65, p < 0.001) than in NOgen (0.09 ± 0.03; mmHg/mL/min). On the other hand, platelet counts and plasma fibrinogen concentration expressed as percent of baseline in control group (63.7 ± 5.7%, 77.2 ± 5.6%; p < 0.05) were greater than those in the NOgen group (60.4 ± 5.1%, 63.2 ± 3.7%). Plasma copper levels in the NOgen group were 2.8 times baseline at 4 h (132.8 ± 4.5 μg/dL) and unchanged in the controls. This study demonstrates that NO generating gas exchange fibers could be a potentially effective way to control coagulation inside artificial lungs.
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Affiliation(s)
- Kagya A Amoako
- Departments of Surgery, University of Michigan Medical Center, 1150 W Medical Center Drive B560B MSRBII, Ann Arbor, MI 48109-0686; Department of Internal Medicine, Cardiology, University of Michigan Medical Center; Department of Chemistry, University of Michigan, Ann Arbor, MI
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Tiruvoipati R, Botha JA, Pilcher D, Bailey M. Carbon dioxide clearance in critical care. Anaesth Intensive Care 2013; 41:157-62. [PMID: 23530782 DOI: 10.1177/0310057x1304100129] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023]
Abstract
Lung protective ventilation limiting tidal volumes and airway pressures were proven to reduce mortality in patients with acute severe respiratory failure. Hypercapnia and hypercapnic acidosis is often noted with lung protective ventilation. While the protective effects of lung protective ventilation are well recognised, the role of hypercapnia and hypercapnic acidosis remains debatable. Some clinicians argue that hypercapnia and hypercapnic acidosis protect the lungs and may be associated with improved outcomes. To the contrary, some clinicians do not tolerate hypercapnic acidosis and use various techniques including extracorporeal carbon dioxide elimination to treat hypercapnia and acidosis. This review aims at defining the effects of hypercapnia and hypercapnic acidosis with a focus on the pros and cons of clearing carbon dioxide and the modalities that may enhance carbon dioxide clearance.
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Affiliation(s)
- R Tiruvoipati
- Department of Intensive Care Medicine, Frankston Hospital, Frankston, Victoria, Australia.
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Cove ME, MacLaren G, Federspiel WJ, Kellum JA. Bench to bedside review: Extracorporeal carbon dioxide removal, past present and future. CRITICAL CARE : THE OFFICIAL JOURNAL OF THE CRITICAL CARE FORUM 2012; 16:232. [PMID: 23014710 PMCID: PMC3682237 DOI: 10.1186/cc11356] [Citation(s) in RCA: 88] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
Abstract
Acute respiratory distress syndrome (ARDS) has a substantial mortality rate and annually affects more than 140,000 people in the USA alone. Standard management includes lung protective ventilation but this impairs carbon dioxide clearance and may lead to right heart dysfunction or increased intracranial pressure. Extracorporeal carbon dioxide removal has the potential to optimize lung protective ventilation by uncoupling oxygenation and carbon dioxide clearance. The aim of this article is to review the carbon dioxide removal strategies that are likely to be widely available in the near future. Relevant published literature was identified using PubMed and Medline searches. Queries were performed by using the search terms ECCOR, AVCO2R, VVCO2R, respiratory dialysis, and by combining carbon dioxide removal and ARDS. The only search limitation imposed was English language. Additional articles were identified from reference lists in the studies that were reviewed. Several novel strategies to achieve carbon dioxide removal were identified, some of which are already commercially available whereas others are in advanced stages of development.
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Abstract
Despite advances in the therapy for acute lung injury and adult respiratory distress syndrome, mortality remains high. The iatrogenic risk of ventilator-induced lung injury might contribute to this high mortality because the lungs are hyperinflated. Low tidal volume and inspiratory pressure are surrogates for the stress and strain concept; but lung compliance, transpulmonary pressure, and chest wall elastance might differ in individual patients. In previous published studies, an increasing number of patients were treated successfully with extracorporeal support. Extracorporeal membrane oxygenation and interventional lung assist allow ultraprotective ventilation strategies. However, these assists have different technical aspects and different indications.
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Aravantagi A, Patra KP, Shekar S, Scott LK. Pumpless arteriovenous carbon dioxide removal: A novel simplified strategy for severe asthma in children. Indian J Crit Care Med 2012; 15:224-6. [PMID: 22346033 PMCID: PMC3271558 DOI: 10.4103/0972-5229.92078] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Abstract
Status asthmaticus unresponsive to pharmacotherapy is conventionally managed with mechanical ventilation, which has its inherent challenges due to barotrauma, dynamic hyperinflation and autopositive end-expiratory pressure (auto-PEEP). Extracorporeal membrane oxygenation has been used as a last resort in respiratory failure due to refractory asthma; however, it entails many complications. In contrast, arteriovenous carbon dioxide removal (AVCO2R) is a novel strategy that has been shown to be highly effective in adults with acute respiratory failure. Only one pediatric case series of pediatric asthma managed with AVCO2R have been published so far. We herein report a case of severe asthma in a 9-year-old boy who developed severe hypercapnia (Pco2 97 mmHg) and acidosis (pH 7.09) despite being on mechanical ventilation. Within 4 h of initiation of AVCO2R, PCo2 drastically reduced to near-normal levels. He was discharged on day 9 of hospital stay without any complications.
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Affiliation(s)
- Avinash Aravantagi
- Critical Care Division, Department of Pediatrics, Louisiana State University Health Sciences Center, Shreveport, LA, USA
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Baker A, Richardson D, Craig G. Extracorporeal Carbon Dioxide Removal (ECCO2R) in Respiratory Failure: An Overview, and where Next? J Intensive Care Soc 2012. [DOI: 10.1177/175114371201300313] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Extracorporeal carbon dioxide removal (ECCO2R) is used to facilitate protective ventilation strategies and to treat severe hypercapnic acidosis that is refractory to mechanical ventilation. There is an increasing amount of interest in the use of ECCO2R but there are no recommendations for its use that take the most recent evidence into account. In 2008, the National Institute of Health and Clinical Excellence (NICE) published guidelines on ‘Arteriovenous Extracorporeal Membrane Carbon Dioxide Removal.’1 However, since that time there have been a number of studies in the area and some significant technological advances including the introduction of commercially available VV-ECCO2R systems. The aim of this article is to provide an overview of ECCO2R, review the literature relating to its use and discuss its future role in the intensive care setting.
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Affiliation(s)
- Andrew Baker
- Specialist Trainee year 7, Anaesthetics and Intensive Care Medicine, Southampton General Hospital
| | - Dominic Richardson
- Consultant in Anaesthetics and Intensive Care Medicine, Southampton General Hospital
| | - Gordon Craig
- Consultant in Anaesthetics and Intensive Care medicine, Queen Alexandra Hospital, Portsmouth
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Kopp R, Bensberg R, Wardeh M, Rossaint R, Kuhlen R, Henzler D. Pumpless arterio-venous extracorporeal lung assist compared with veno-venous extracorporeal membrane oxygenation during experimental lung injury. Br J Anaesth 2012; 108:745-53. [DOI: 10.1093/bja/aes021] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022] Open
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Complete Respiratory Support with AVCO2R and CPAP-Mimic Ventilation for Total Gas Exchange in Sheep. ASAIO J 2012; 58:155-9. [DOI: 10.1097/mat.0b013e3182455b98] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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Kaushik M, Wojewodzka-Zelezniakowicz M, Cruz DN, Ferrer-Nadal A, Teixeira C, Iglesias E, Kim JC, Braschi A, Piccinni P, Ronco C. Extracorporeal Carbon Dioxide Removal: The Future of Lung Support Lies in the History. Blood Purif 2012; 34:94-106. [DOI: 10.1159/000341904] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
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McNicholas JJK, Henning JD. Major military trauma: decision making in the ICU. J ROY ARMY MED CORPS 2011; 157:S284-8. [PMID: 22049809 DOI: 10.1136/jramc-157-03s-05] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/04/2022]
Abstract
The management of trauma in the field intensive care unit has evolved in recent years. Key issues in current practice and organisation are discussed, with particular attention to areas where civilian and military practice differs. Possible future improvements are explored.
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Russ M, Deja M, Ott S, Bedarf J, Keckel T, Hiebl B, Wagner JJ, Unger JK. Experimental High-Volume Hemofiltration With Predilutional Tris-Hydroxymethylaminomethane for Correction of Low Tidal Volume Ventilation-Induced Acidosis. Artif Organs 2011; 35:E108-18. [DOI: 10.1111/j.1525-1594.2011.01204.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Metzger JC, Eastman AL, Pepe PE. Year in review 2009: Critical Care--cardiac arrest, trauma and disasters. CRITICAL CARE : THE OFFICIAL JOURNAL OF THE CRITICAL CARE FORUM 2010; 14:242. [PMID: 21122166 PMCID: PMC3220035 DOI: 10.1186/cc9302] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
During 2009, Critical Care published nine papers on various aspects of resuscitation, prehospital medicine, trauma care and disaster response. One article demonstrated that children as young as 9 years of age can learn cardiopulmonary resuscitation (CPR) effectively, although, depending on their size, some may have difficulty performing it. Another paper showed that while there was a trend toward mild therapeutic hypothermia reducing S-100 levels, there was no statistically significant change. Another predictor study also showed a strong link between acute kidney injury and neurologic outcome while another article described a program in which kidneys were harvested from cardiac arrest patients and showed an 89% graft survival rate. One experimental investigation indicated that when a pump-less interventional lung assist device is present, leaving the device open (unclamped) while performing CPR has no harmful effects on mean arterial pressures and it may have positive effects on blood oxygenation and CO2 clearance. One other study, conducted in the prehospital environment, found that end-tidal CO2 could be useful in diagnosing pulmonary embolism. Three articles addressed disaster medicine, the first of which described a triage system for use during pandemic influenza that demonstrated high reliability in delineating patients with a good chance of survival from those likely to die. The other two studies, both drawn from the 2008 Sichuan earthquake experience, showed success in treating crush injured patients in an on-site tent ICU and, in the second case, how the epidemiology of earthquake injuries and related factors predicted mortality.
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Affiliation(s)
- Jeffery C Metzger
- Department of Surgery/Emergency Medicine, University of Texas Southwestern Medical Center at Dallas, 5323 Harry Hines Blvd, Mail Code 8579, Dallas, TX 75390-8579, USA.
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Oh HI, Ye SH, Johnson CA, Woolley JR, Federspiel WJ, Wagner WR. Hemocompatibility assessment of carbonic anhydrase modified hollow fiber membranes for artificial lungs. Artif Organs 2010; 34:439-42. [PMID: 20633159 DOI: 10.1111/j.1525-1594.2009.00882.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Hollow fiber membrane (HFM)-based artificial lungs can require a large blood-contacting membrane surface area to provide adequate gas exchange. However, such a large surface area presents significant challenges to hemocompatibility. One method to improve carbon dioxide (CO(2)) transfer efficiency might be to immobilize carbonic anhydrase (CA) onto the surface of conventional HFMs. By catalyzing the dehydration of bicarbonate in blood, CA has been shown to facilitate diffusion of CO(2) toward the fiber membranes. This study evaluated the impact of surface modifying a commercially available microporous HFM-based artificial lung on fiber blood biocompatibility. A commercial poly(propylene) Celgard HFM surface was coated with a siloxane, grafted with amine groups, and then attached with CA which has been shown to facilitate diffusion of CO(2) toward the fiber membranes. Results following acute ovine blood contact indicated no significant reduction in platelet deposition or activation with the siloxane coating or the siloxane coating with grafted amines relative to base HFMs. However, HFMs with attached CA showed a significant reduction in both platelet deposition and activation compared with all other fiber types. These findings, along with the improved CO(2) transfer observed in CA modified fibers, suggest that its incorporation into HFM design may potentiate the design of a smaller, more biocompatible HFM-based artificial lung.
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Affiliation(s)
- Heung-Il Oh
- McGowan Institute for Regenerative Medicine, University of Pittsburgh, 100 Technology Drive, Pittsburgh, PA 15219, USA
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Abstract
BACKGROUND Aventilatory mass flow (AVMF) is routinely used for apneic oxygenation in various clinical procedures but no data exist to quantitatively describe the gas flow. This study was designed to determine the amount of AVMF during the clinical situation of apnea to force spontaneous respiration at the end of anaesthesia with controlled ventilation. MATERIALS AND METHODS A total of 200 patients undergoing anesthesia for routine surgery were examined. AVMF was analyzed with a high resolution, low gas stream, thermal mass flow analyzer. The intended recording time was 3 min. RESULTS Measurement was reliably successful and suitable for evaluation in only 23 patients. AVMF-induced gas flow started on average 17.9 + or - 9.4 s after onset of apnea. Maximum flow was reached within 158 + or - 20 s and determined to be 135 + or - 32 ml/min. The slope of increase of gas flow showed a rapid oscillation corresponding to the heart rate in all patients and in 14 out of 23 patients a slow oscillation with a frequency of 8.9 + or - 1.8/min. CONCLUSIONS During apnea AVMF develops in a non-linear fashion. The maximum flow observed is closely related to the estimated oxygen consumption. Heart rate synchronous flow variations are probably caused by intrathoracic volume variations due to heart action. The low frequency oscillations correspond to the frequency of Traube-Hering-Mayer waves.
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Sanchez-Lorente D, Go T, Jungebluth P, Rovira I, Mata M, Ayats MC, Macchiarini P. Single double-lumen venous–venous pump-driven extracorporeal lung membrane support. J Thorac Cardiovasc Surg 2010; 140:558-63, 563.e1-2. [DOI: 10.1016/j.jtcvs.2009.12.057] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/22/2009] [Revised: 11/08/2009] [Accepted: 12/12/2009] [Indexed: 11/12/2022]
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Wiebe K, Poeling J, Arlt M, Philipp A, Camboni D, Hofmann S, Schmid C. Thoracic Surgical Procedures Supported by a Pumpless Interventional Lung Assist. Ann Thorac Surg 2010; 89:1782-7; discussion 1788. [DOI: 10.1016/j.athoracsur.2010.03.012] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/02/2009] [Revised: 03/01/2010] [Accepted: 03/01/2010] [Indexed: 10/19/2022]
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Kopp R, Bensberg R, Henzler D, Niewels A, Randerath S, Rossaint R, Kuhlen R. Hemocompatibility of a Miniaturized Extracorporeal Membrane Oxygenation and a Pumpless Interventional Lung Assist in Experimental Lung Injury. Artif Organs 2010; 34:13-21. [DOI: 10.1111/j.1525-1594.2009.00791.x] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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Cressoni M, Zanella A, Epp M, Corti I, Patroniti N, Kolobow T, Pesenti A. Decreasing pulmonary ventilation through bicarbonate ultrafiltration: an experimental study. Crit Care Med 2009; 37:2612-8. [PMID: 19602976 DOI: 10.1097/ccm.0b013e3181a5668a] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
OBJECTIVE : To demonstrate the technical feasibility of CO2 removal with a commercial hemofilter and a replacement solution containing sodium hydroxide to replace bicarbonate. DESIGN : Prospective animal experiment in sheep. SUBJECTS : Seven mixed-breed female sheep. INTERVENTIONS : Blood ultrafiltrate containing half of the metabolic production of CO2 was removed with a commercial hemofilter and a replacement solution containing sodium hydroxide was given as replacement. Minute ventilation was lowered to less than half of its baseline value. Ultrafiltration was stopped at 18 hrs, and Paco2 was allowed to increase for about 1 hr; at this time, the sheep were electively killed. MEASUREMENTS AND MAIN RESULTS : Every 6 hrs, blood was sampled from the carotid artery, the pulmonary artery, and from the extracorporeal perfusion circuit (before the hemofilter, immediately after the hemofilter, and after mixing with the replacement solution). To maintain normocapnia, minute ventilation was reduced from 3.8 +/- 0.1 L/min to 1.9 +/- 0.7 L/min; Paco2 remained near constant during the study. The average blood pH, after mixing with the replacement solution, was 7.64 +/- 0.12. One hour after the ultrafiltration had stopped, Paco2 had increased from 36.7 +/- 4.2 torr (4.9 +/- 0.6 kPa) to 59.6 +/- 9 torr (7.9 +/- 1.2 kPa) (p < .01) and blood pH had decreased from 7.317 +/- 0.041 to 7.151 +/- 0.051 (p < .01). CONCLUSION : CO2 removal with bicarbonate ultrafiltration may be an effective treatment for patients with respiratory failure.
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Affiliation(s)
- Massimo Cressoni
- National Institutes of Health, National Heart, Lung, and Blood Institute (MC, AZ, ME, IC, TK), Section of Pulmonary and Cardiac Assist Devices, Pulmonary and Critical Care Medicine Branch, Bethesda, MD, USA.
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Zanella A, Patroniti N, Isgrò S, Albertini M, Costanzi M, Pirrone F, Scaravilli V, Vergnano B, Pesenti A. Blood acidification enhances carbon dioxide removal of membrane lung: an experimental study. Intensive Care Med 2009; 35:1484-7. [DOI: 10.1007/s00134-009-1513-5] [Citation(s) in RCA: 51] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2009] [Accepted: 04/29/2009] [Indexed: 11/24/2022]
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Venovenous carbon dioxide removal in chronic obstructive pulmonary disease: experience in one patient. ASAIO J 2009; 55:420-2. [PMID: 19512886 DOI: 10.1097/mat.0b013e3181a7b55d] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
Chronic obstructive pulmonary disease (COPD) is the fourth leading cause of death in the United States. Acute exacerbations of COPD account for up to 84% of the total economic cost of this disease. The altered mechanics of the COPD patient represent a unique challenge to the clinician instituting assisted ventilation in this population. We developed an alternative mode of limited extracorporeal support termed Venovenous carbon dioxide removal (VVCO2R). We report our first case using VVCO2R, a 42-year-old white woman with a history of COPD and asthma, who was a heavy smoker at the time of admission. We utilized a compact, low flow pediatric extracorporeal circuit interposed with a low resistance gas exchange device. Venovenous carbon dioxide removal allowed for a reduction in the patient's minute ventilation to 30% of baseline with improved arterial blood gases (ABGs), a reduction in peak airway pressures and improvement in her hyperinflation. Our experience demonstrates that this system can effectively remove CO2 safely in a single cannula venous configuration while maintaining minimal anticoagulation. We believe this system could potentially be utilized in any medical or surgical intensive care unit.
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Extracorporeal Lung Assist for Acute Respiratory Distress Syndrome: Past, Present and Future. Intensive Care Med 2009. [DOI: 10.1007/978-0-387-77383-4_22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Zick G, Schädler D, Elke G, Pulletz S, Bein B, Scholz J, Frerichs I, Weiler N. Effects of interventional lung assist on haemodynamics and gas exchange in cardiopulmonary resuscitation: a prospective experimental study on animals with acute respiratory distress syndrome. CRITICAL CARE : THE OFFICIAL JOURNAL OF THE CRITICAL CARE FORUM 2009; 13:R17. [PMID: 19210772 PMCID: PMC2688135 DOI: 10.1186/cc7716] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/19/2008] [Revised: 01/20/2009] [Accepted: 02/11/2009] [Indexed: 11/25/2022]
Abstract
Introduction Interventional lung assist (ILA), based on the use of a pumpless extracorporeal membrane oxygenator, facilitates carbon dioxide (CO2) elimination in acute respiratory distress syndrome (ARDS). It is unclear whether an ILA system should be clamped during cardiopulmonary resuscitation (CPR) in patients with ARDS or not. The aim of our study was to test the effects of an ILA on haemodynamics and gas exchange during CPR on animals with ARDS and to establish whether the ILA should be kept open or clamped under these circumstances. Methods The study was designed to be prospective and experimental. The experiments were performed on 12 anaesthetised and mechanically ventilated pigs (weighing 41 to 58 kg). One femoral artery and one femoral vein were cannulated and connected to an ILA. ARDS was induced by repeated bronchoalveolar lavage. An indwelling pacemaker was used to initiate ventricular fibrillation and chest compressions were immediately started and continued for 30 minutes. In six animals, the ILA was kept open and in the other six it was clamped. Results Systolic and mean arterial pressures did not differ significantly between the groups. With the ILA open mean ± standard deviation systolic blood pressures were 89 ± 26 mmHg at 5 minutes, 71 ± 28 mmHg at 10 minutes, 63 ± 33 mmHg at 20 minutes and 83 ± 23 mmHg at 30 minutes. The clamped ILA system resulted in systolic pressures of 77 ± 30 mmHg, 90 ± 23 mmHg, 72 ± 11 mmHg and 72 ± 22 mmHg, respectively. In the group with the ILA system open, arterial partial pressure of CO2 was significantly lower after 10, 20 and 30 minutes of CPR and arterial partial pressure of oxygen was higher 20 minutes after the onset of CPR (191 ± 140 mmHg versus 57 ± 14 mmHg). End-tidal partial pressure of CO2 decreased from 46 ± 23 Torr (ILA open) and 37 ± 9 Torr (ILA clamped) before intervention to 8 ± 5 Torr and 8 ± 10 Torr, respectively, in both groups after 30 minutes of CPR. Conclusions Our results indicate that in an animal model of ARDS, blood pressures were not impaired by keeping the ILA system open during CPR compared with the immediate clamping of the ILA with the onset of CPR. The effect of ILA on gas exchange implied a beneficial effect.
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Affiliation(s)
- Günther Zick
- Department of Anesthesiology and Intensive Care Medicine, University Medical Center Schleswig-Holstein, Campus Kiel, Kiel, Germany.
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The clinical research enterprise in critical care: what's right, what's wrong, and what's ahead? Crit Care Med 2009; 37:S1-9. [PMID: 19104206 DOI: 10.1097/ccm.0b013e318192074c] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
Intensivists have been remarkably successful in using randomized controlled trials to assess aspects of current practice. Unfortunately, this success has not been mirrored in trials of new pharmacotherapy, despite convincing pathophysiological rationales and encouraging preliminary studies. Misunderstandings of biological processes and flawed early clinical studies have led to the almost universal failure of fundamentally new treatments subjected to large phase III trials, despite their sound methodology. Compounding these problems is the tendency for new approaches to be either implemented widely on the basis of relatively poor studies or ignored despite strong supporting evidence. Having mastered the principles of evidence-based medicine in assessing existing therapy, intensivists have established a strong foundation. Critical care medicine must now embrace the challenge of translating a more solid understanding of basic disease mechanisms into widely implemented treatments.
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Wang-Zwische double lumen cannula-toward a percutaneous and ambulatory paracorporeal artificial lung. ASAIO J 2008; 54:606-11. [PMID: 19033774 DOI: 10.1097/mat.0b013e31818c69ab] [Citation(s) in RCA: 123] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
We are developing a high performance double lumen cannula (DLC) for a minimally invasive, ambulatory and percutaneous paracorporeal artificial lung (PAL). The Wang-Zwische (W-Z) DLC was designed for percutaneous insertion into the Internal Jugular (IJ) vein with a drainage lumen open to both the superior vena cava (SVC) and the inferior vena cava (IVC) maximizing venous drainage. A separate collapsible but nondistensible membrane infusion lumen open to the right atrium (RA) achieves minimal recirculation allowing for total gas exchange. The W-Z DLC prototypes are made by a proprietary dip molding process with the "molded in" flat wire spiral stainless steel spring resulting in a flexible yet kink resistant thin wall (0.1 mm) outer cannula with one piece construction. With the ultra thin membrane infusion lumen collapsed, an introducer shaft fits tightly within the drainage lumen to facilitate insertion with placement at the SVC-RA-IVC junction. The W-Z DLC prototypes were tested while connected to a compact pump-gas exchanger circuit in three sheep (2 acute and one 15 day performance study). Insertion was simple, using standard percutaneous insertion techniques. Recirculation was as low as 2%. The 15 day performance study demonstrated our prototype 26 Fr W-Z DLC can achieve 2 L/min blood flow with minimal recirculation. The W-Z DLC design minimizes recirculation rate, maximizes flow lumen cross-sectional area, and maximizes achievable blood flow to enhance gas exchange performance allowing for one site percutaneous venovenous support.
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Jungebluth P, Iglesias M, Go T, Sibila O, Macchiarini P. Optimal Positive End-Expiratory Pressure During Pumpless Extracorporeal Lung Membrane Support. Artif Organs 2008; 32:885-90. [DOI: 10.1111/j.1525-1594.2008.00646.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Conrad SA, Green R, Scott LK. Near-fatal pediatric asthma managed with pumpless arteriovenous carbon dioxide removal. Crit Care Med 2008; 35:2624-9. [PMID: 17901835 DOI: 10.1097/01.ccm.0000288104.97602.b3] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
Abstract
OBJECTIVE To describe the use of pumpless arteriovenous carbon dioxide removal in support of four pediatric patients with near-fatal asthma. DESIGN Report of four cases. SETTING Tertiary care university pediatric intensive care unit. PATIENTS Four pediatric patients, ages 4, 10, 12, and 13, were intubated and initially managed with positive pressure ventilation for severe respiratory failure. Despite pharmacologic therapy with inhaled beta-agonists, inhaled anticholinergics, systemic corticosteroids, and intravenous magnesium, marked progressive hypercapnia and acidosis rapidly developed requiring high levels of positive pressure ventilation. INTERVENTIONS Application of pumpless arteriovenous carbon dioxide removal (AVCO2R) via percutaneous femoral cannulation. MEASUREMENT AND MAIN RESULTS Arterial or mixed venous carbon dioxide partial pressure (PCO2) and pH were measured before and at intervals following initiation of AVCO2R. Before cannulation, PCO2 was elevated to 100, 108, 90, and 186 mm Hg in the four patients, with corresponding pH of 7.07, 6.96, 7.09, and 6.80, respectively. Pco2 levels were reduced to more acceptable levels (37-57 mm Hg) within 2-4 hrs of initiation of AVCO2R, with corresponding improvements in pH despite reductions in ventilatory frequency and tidal volumes to safe levels. Duration of support ranged from 18 hrs to 5 days during resolution of bronchospasm. No red blood cell or platelet transfusions were required, and no complications resulted from AVCO2R or from mechanical ventilation. All patients were discharged from the hospital without sequelae. CONCLUSIONS Percutaneous cannulation with a simplified pumpless extracorporeal circuit is capable of removing sufficient carbon dioxide to allow application of a protective ventilatory strategy in severe hypercapnic pediatric respiratory failure. The procedure was safely applied without complications in four pediatric patients as young as 4 yrs of age.
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Affiliation(s)
- Steven A Conrad
- Extracorporeal Life Support Program, Critical Care Medicine Division, Deparlment of Medicine, Louisiana State University Health Sciences Center, Shreveport, LA, USA.
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Ambulatory Oxygenator Right Ventricular Assist Device for Total Right Heart and Respiratory Support. Ann Thorac Surg 2007; 84:1699-703. [DOI: 10.1016/j.athoracsur.2007.03.068] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/15/2006] [Revised: 03/20/2007] [Accepted: 03/21/2007] [Indexed: 11/20/2022]
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Schmalstieg FC, Keeney SE, Rudloff HE, Palkowetz KH, Cevallos M, Zhou X, Cox RA, Hawkins HK, Traber DL, Zwischenberger JB. Arteriovenous CO2 removal improves survival compared to high frequency percussive and low tidal volume ventilation in a smoke/burn sheep acute respiratory distress syndrome model. Ann Surg 2007; 246:512-21; discussion 521-3. [PMID: 17717455 PMCID: PMC1959342 DOI: 10.1097/sla.0b013e318148c6e6] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
Abstract
UNLABELLED OBJECTIVES AND SUMMARY BACKGROUND: Low tidal volume ventilation (LTV) has improved survival with acute respiratory distress syndrome (ARDS) by reducing lung stretch associated with volutrauma and barotrauma. Additional strategies to reduce lung stretch include arteriovenous carbon dioxide removal (AVCO2R), and high frequency percussive ventilation (HFPV). We performed a prospective, randomized study comparing these techniques in our clinically relevant LD100 sheep model of ARDS to compare survival, pathology, and inflammation between the 3 ventilator methods. METHODS Adult sheep (n = 61) received smoke inhalation (48 breaths) and a 40% third-degree burn. After ARDS developed (Pao2/FiO2 <200), animals were randomized. In experiment 1, animals were killed at 48 hours after randomization. Hemodynamics, pulmonary function, injury scores, myeloperoxidase (MPO) in lung tissues and neutrophils, IL-8 in lung tissues, and apoptosis were evaluated. In experiment 2, the end point was survival to 72 hours after onset of ARDS or end-of-life criteria with extension of the same studies performed in experiment 1. RESULTS There were no differences in hemodynamics, but minute ventilation was lower in the AVCO2R group and Paco2 for the HFPV and AVCO2R animals remained lower than LTV. Airway obstruction and injury scores were not different among the 3 ventilation strategies. In experiment 1, lung tissue MPO and IL-8 were not different among the ventilation strategies. However, in experiment 2, lung tissue MPO was significantly lower for AVCO2R-treated animals (AVCO2R < HFPV < LTV). TUNEL staining showed little DNA breakage in neutrophils from experiment 1, but significantly increased breakage in all 3 ventilator strategies in experiment 2. In contrast, AVCO2R tissue neutrophils showed significant apoptosis at 72 hours post-ARDS criteria as measured by nuclear condensation (P < 0.001). Survival 72 hours post-ARDS criteria was highest for AVCO2R (71%) compared with HFPV (55%) and LTV (33%) (AVCO2R vs. LTV, P = 0.05). CONCLUSIONS Significantly more animals survived AVCO2R than LTV. In experiment 2, Lung MPO was significantly lower for AVCO2R, compared with LTV (P < 0.05). This finding taken together with the TUNEL and neutrophil apoptosis results, suggested that disposition of neutrophils 72 hours post-ARDS criteria was different among the ventilatory strategies with neutrophils from AVCO2R-treated animals removed chiefly through apoptosis, but in the cases of HFPV and LTV, dying by necrosis in lung tissue.
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Affiliation(s)
- Frank C Schmalstieg
- Department of Pediatrics, University of Texas Medical Branch, Galveston, TX 77555, USA.
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An Ambulatory Pulmonary and Right Heart Assist Device (OxyRVAD) in an Ovine Survival Model. J Heart Lung Transplant 2007; 26:974-9. [DOI: 10.1016/j.healun.2007.07.019] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2007] [Revised: 07/09/2007] [Accepted: 07/15/2007] [Indexed: 11/18/2022] Open
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Pumpless extracorporeal lung assist for protective mechanical ventilation in experimental lung injury*. Crit Care Med 2007; 35:2359-66. [DOI: 10.1097/01.ccm.0000281857.87354.a5] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Walles T. Clinical experience with the iLA Membrane Ventilator pumpless extracorporeal lung-assist device. Expert Rev Med Devices 2007; 4:297-305. [PMID: 17488224 DOI: 10.1586/17434440.4.3.297] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
Extracorporeal gas exchange by extracorporeal membrane oxygenation has been established clinically in patients with acute lung failure. The interventional lung-assist (iLA) Membrane Ventilator device (Novalung) is a sophisticated representative of a new generation of pumpless extracorporeal lung-assist devices that are driven by the patient's cardiac output and therefore, do not require extracorporeal pump assistance. The system is characterized by a new membrane gas exchange system with optimized blood flow that is integrated in an arteriovenous bypass established by vascular cannulation. This particular pumpless extracorporeal lung-assist device was applied in 1800 patients for artificial lung assistance with easy use and low cost. This article reviews the present state of clinical Novalung device implementation focusing on encountered limitations and conceivable future developments in the field.
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Affiliation(s)
- Thorsten Walles
- Klinik Schillerhöhe, Department of Thoracic Surgery, Solitudestrasse 18, 70839 Gerlingen, Germany.
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Kaar JL, Oh HI, Russell AJ, Federspiel WJ. Towards improved artificial lungs through biocatalysis. Biomaterials 2007; 28:3131-9. [PMID: 17433433 PMCID: PMC3427004 DOI: 10.1016/j.biomaterials.2007.03.021] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/02/2006] [Accepted: 03/12/2007] [Indexed: 01/11/2023]
Abstract
Inefficient CO(2) removal due to limited diffusion represents a significant barrier in the development of artificial lungs and respiratory assist devices, which use hollow fiber membranes (HFMs) as the blood-gas interface and can require large blood-contacting membrane area. To offset the underlying diffusional challenge, "bioactive" HFMs that facilitate CO(2) diffusion were prepared via covalent immobilization of carbonic anhydrase (CA), an enzyme which catalyzes the conversion of bicarbonate in blood to CO(2), onto the surface of plasma-modified conventional HFMs. This study examines the impact of enzyme attachment on the diffusional properties and the rate of CO(2) removal of the bioactive membranes. Plasma deposition of surface reactive hydroxyls, to which CA could be attached, did not change gas permeance of the HFMs or generate membrane defects, as determined by scanning electron microscopy, when low plasma discharge power and short exposure times were employed. Cyanogen bromide activation of the surface hydroxyls and subsequent modification with CA resulted in near monolayer enzyme coverage (88%) on the membrane. The effect of increased plasma discharge power and exposure time on enzyme loading was negligible while gas permeance studies showed enzyme attachment did not impede CO(2) or O(2) diffusion. Furthermore, when employed in a model respiratory assist device, the bioactive membranes improved CO(2) removal rates by as much as 75% from physiological bicarbonate solutions with no enzyme leaching. These results demonstrate the potential of bioactive HFMs with immobilized CA to enhance CO(2) exchange in respiratory devices.
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Affiliation(s)
- Joel L Kaar
- McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, PA 15219, USA
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