Gregor Loosen1, Alice Marguerite Conrad2, Michael Hagman3,4, Nils Essert2, Manfred Thiel2, Thomas Luecke2, Joerg Krebs5. 1. Department of Cardiothoracic Anaesthesia and Intensive Care, Royal Papworth Hospital NHS Foundation Trust, Papworth Road, Cambridge Biomedical Campus, Cambridge, CB2 0AY, UK. 2. Department of Anaesthesiology and Critical Care Medicine, University Medical Centre Mannheim, Medical Faculty Mannheim of the University of Heidelberg, Theodor-Kutzer Ufer 1-3, 68167, Mannheim, Germany. 3. Department of Computational Linguistics, University of Heidelberg, Im Neuenheimer Feld 325, 69120, Heidelberg, Germany. 4. Interdisciplinary Centre for Scientific Computing, University of Heidelberg, Im Neuenheimer Feld 205, 69120, Heidelberg, Germany. 5. Department of Anaesthesiology and Critical Care Medicine, University Medical Centre Mannheim, Medical Faculty Mannheim of the University of Heidelberg, Theodor-Kutzer Ufer 1-3, 68167, Mannheim, Germany. Joerg.Krebs@umm.de.
Abstract
BACKGROUND: We tested the effect of different blood flow levels in the extracorporeal circuit on the measurements of cardiac stroke volume (SV), global end-diastolic volume index (GEDVI) and extravascular lung water index derived from transpulmonary thermodilution (TPTD) in 20 patients with severe acute respiratory distress syndrome (ARDS) treated with veno-venous extracorporeal membrane oxygenation (ECMO). METHODS: Comparative SV measurements with transesophageal echocardiography and TPTD were performed at least 5 times during the treatment of the patients. The data were interpreted with a Bland-Altman analysis corrected for repeated measurements. The interchangeability between both measurement modalities was calculated and the effects of extracorporeal blood flow on SV measurements with TPTD was analysed with a linear mixed effect model. GEDVI and EVLWI measurements were performed immediately before the termination of the ECMO therapy at a blood flow of 6 l/min, 4 l/min and 2 l/min and after the disconnection of the circuit in 7 patients. RESULTS: 170 pairs of comparative SV measurements were analysed. Average difference between the two modalities (bias) was 0.28 ml with an upper level of agreement of 40 ml and a lower level of agreement of -39 ml within a 95% confidence interval and an overall interchangeability rate between TPTD and Echo of 64%. ECMO blood flow did not influence the mean bias between Echo and TPTD (0.03 ml per l/min of ECMO blood flow; p = 0.992; CI - 6.74 to 6.81). GEDVI measurement was not significantly influenced by the blood flow in the ECMO circuit, whereas EVLWI differed at a blood flow of 6 l/min compared to no ECMO flow (25.9 ± 10.1 vs. 11.0 ± 4.2 ml/kg, p = 0.0035). CONCLUSIONS: Irrespectively of an established ECMO therapy, comparative SV measurements with Echo and TPTD are not interchangeable. Such caveats also apply to the interpretation of EVLWI, especially with a high blood flow in the extracorporeal circulation. In such situations, the clinician should rely on other methods of evaluation of the amount of lung oedema with the haemodynamic situation, vasopressor support and cumulative fluid balance in mind. TRIAL REGISTRATION: German Clinical Trials Register (DRKS00021050). Registered 03/30/2020 https://www.drks.de/drks_web/navigate.do?navigationId=trial.HTML&TRIAL_ID=DRKS00017237.
BACKGROUND: We tested the effect of different blood flow levels in the extracorporeal circuit on the measurements of cardiac stroke volume (SV), global end-diastolic volume index (GEDVI) and extravascular lung water index derived from transpulmonary thermodilution (TPTD) in 20 patients with severe acute respiratory distress syndrome (ARDS) treated with veno-venous extracorporeal membrane oxygenation (ECMO). METHODS: Comparative SV measurements with transesophageal echocardiography and TPTD were performed at least 5 times during the treatment of the patients. The data were interpreted with a Bland-Altman analysis corrected for repeated measurements. The interchangeability between both measurement modalities was calculated and the effects of extracorporeal blood flow on SV measurements with TPTD was analysed with a linear mixed effect model. GEDVI and EVLWI measurements were performed immediately before the termination of the ECMO therapy at a blood flow of 6 l/min, 4 l/min and 2 l/min and after the disconnection of the circuit in 7 patients. RESULTS: 170 pairs of comparative SV measurements were analysed. Average difference between the two modalities (bias) was 0.28 ml with an upper level of agreement of 40 ml and a lower level of agreement of -39 ml within a 95% confidence interval and an overall interchangeability rate between TPTD and Echo of 64%. ECMO blood flow did not influence the mean bias between Echo and TPTD (0.03 ml per l/min of ECMO blood flow; p = 0.992; CI - 6.74 to 6.81). GEDVI measurement was not significantly influenced by the blood flow in the ECMO circuit, whereas EVLWI differed at a blood flow of 6 l/min compared to no ECMO flow (25.9 ± 10.1 vs. 11.0 ± 4.2 ml/kg, p = 0.0035). CONCLUSIONS: Irrespectively of an established ECMO therapy, comparative SV measurements with Echo and TPTD are not interchangeable. Such caveats also apply to the interpretation of EVLWI, especially with a high blood flow in the extracorporeal circulation. In such situations, the clinician should rely on other methods of evaluation of the amount of lung oedema with the haemodynamic situation, vasopressor support and cumulative fluid balance in mind. TRIAL REGISTRATION: German Clinical Trials Register (DRKS00021050). Registered 03/30/2020 https://www.drks.de/drks_web/navigate.do?navigationId=trial.HTML&TRIAL_ID=DRKS00017237.
Authors: Marcelo B P Amato; Maureen O Meade; Arthur S Slutsky; Laurent Brochard; Eduardo L V Costa; David A Schoenfeld; Thomas E Stewart; Matthias Briel; Daniel Talmor; Alain Mercat; Jean-Christophe M Richard; Carlos R R Carvalho; Roy G Brower Journal: N Engl J Med Date: 2015-02-19 Impact factor: 91.245
Authors: Elmi Messaï; Abdesselam Bouguerra; Guy Harmelin; Gabriella Di Lascio; Giovanni Cianchi; Massimo Bonacchi Journal: Intensive Care Med Date: 2012-12-05 Impact factor: 17.440
Authors: Eddy Fan; Lorenzo Del Sorbo; Ewan C Goligher; Carol L Hodgson; Laveena Munshi; Allan J Walkey; Neill K J Adhikari; Marcelo B P Amato; Richard Branson; Roy G Brower; Niall D Ferguson; Ognjen Gajic; Luciano Gattinoni; Dean Hess; Jordi Mancebo; Maureen O Meade; Daniel F McAuley; Antonio Pesenti; V Marco Ranieri; Gordon D Rubenfeld; Eileen Rubin; Maureen Seckel; Arthur S Slutsky; Daniel Talmor; B Taylor Thompson; Hannah Wunsch; Elizabeth Uleryk; Jan Brozek; Laurent J Brochard Journal: Am J Respir Crit Care Med Date: 2017-05-01 Impact factor: 21.405
Authors: Peter T Graf; Christoph Boesing; Isabel Brumm; Jonas Biehler; Kei Wieland Müller; Manfred Thiel; Paolo Pelosi; Patricia R M Rocco; Thomas Luecke; Joerg Krebs Journal: J Intensive Care Date: 2022-03-07