Prolonged extracorporeal membrane oxygenation-assisted support provides improved survival in hypothermic patients with cardiocirculatory arrest

Ruttmann, Elfriede; Weissenbacher, Annemarie; Ulmer, Hanno; Müller, Ludwig; Höfer, Daniel; Kilo, Juliane; Rabl, Walter; Schwarz, Birgit; Laufer, Günther; Antretter, Herwig; Mair, Peter

doi:10.1016/j.jtcvs.2007.03.049

« Previous Next »The Journal of Thoracic and Cardiovascular Surgery
Volume 134, Issue 3 , Pages 594-600, September 2007

Prolonged extracorporeal membrane oxygenation-assisted support provides improved survival in hypothermic patients with cardiocirculatory arrest

Presented at the World Congress of Cardiology, September 2006, Barcelona, Spain.

Elfriede Ruttmann, MD
- Department of Cardiac Surgery, Innsbruck Medical University, Tyrol, Austria
- Address for reprints: Elfriede Ruttmann, MD, Department of Cardiac Surgery, Innsbruck Medical University, Anichstrasse 35, 6020 Innsbruck, Austria.
Annemarie Weissenbacher, MD
- Department of Cardiac Surgery, Innsbruck Medical University, Tyrol, Austria
Hanno Ulmer, PhD
- Department of Medical Statistics, Informatics and Health Economy, Innsbruck Medical University, Tyrol, Austria
Ludwig Müller, MD
- Department of Cardiac Surgery, Innsbruck Medical University, Tyrol, Austria
Daniel Höfer, MD
- Department of Cardiac Surgery, Innsbruck Medical University, Tyrol, Austria
Juliane Kilo, MD
- Department of Cardiac Surgery, Innsbruck Medical University, Tyrol, Austria
Walter Rabl, MD
- Department of Forensic Medicine, Innsbruck Medical University, Tyrol, Austria
Birgit Schwarz, MD
- Department of Anesthesiology and Intensive Care Medicine, Innsbruck Medical University, Tyrol, Austria.
Günther Laufer, MD
- Department of Cardiac Surgery, Innsbruck Medical University, Tyrol, Austria
Herwig Antretter, MD
- Department of Cardiac Surgery, Innsbruck Medical University, Tyrol, Austria
Peter Mair, MD
- Department of Anesthesiology and Intensive Care Medicine, Innsbruck Medical University, Tyrol, Austria.

Received 14 January 2007; received in revised form 12 March 2007; accepted 22 March 2007.

Objective

Extracorporeal circulation is considered the gold standard in the treatment of hypothermic cardiocirculatory arrest; however, few centers use extracorporeal membrane oxygenation instead of standard extracorporeal circulation for this indication. The aim of this study was to evaluate whether extracorporeal membrane oxygenation-assisted resuscitation improves survival in patients with hypothermic cardiac arrest.

Methods

A consecutive series of 59 patients with accidental hypothermia in cardiocirculatory arrest between 1987 and 2006 were included. Thirty-four patients (57.6%) were resuscitated by standard extracorporeal circulation, and 25 patients (42.4%) were resuscitated by extracorporeal membrane oxygenation. Accidental hypothermia was caused by avalanche in 22 patients (37.3%), drowning in 22 patients (37.3%), exposure to cold in 8 patients (13.5%), and falling into a crevasse in 7 patients (11.9%). Multivariate logistic regression analysis was used to compare extracorporeal membrane oxygenation with extracorporeal circulation resuscitation, with adjustment for relevant parameters.

Results

Restoration of spontaneous circulation was achieved in 32 patients (54.2%). A total of 12 patients (20.3%) survived hypothermia. In the extracorporeal circulation group, 64% of the nonsurviving patients who underwent restoration of spontaneous circulation died of severe pulmonary edema, but none died in the extracorporeal membrane oxygenation group. In multivariate analysis, extracorporeal membrane oxygenation-assisted resuscitation showed a 6.6-fold higher chance for survival (relative risk: 6.6, 95% confidence interval: 1.2–49.3, P = .042). Asphyxia-related hypothermia (avalanche or drowning) was the most predictive adverse factor for survival (relative risk: 0.09, 95% confidence interval: 0.01–0.60, P = .013). Potassium and pH failed to show statistical significance in the multivariate analysis.

Conclusions

Extracorporeal rewarming with an extracorporeal membrane oxygenation system allows prolonged cardiorespiratory support after initial resuscitation. Our data indicate that prolonged extracorporeal membrane oxygenation support reduces the risk of intractable cardiorespiratory failure commonly observed after rewarming.

CTSNet classification: 25, 27

Abbreviations and Acronyms: CI, confidence interval, ECC, extracorporeal circulation, ECMO, extracorporeal membrane oxygenation, ROSC, return of spontaneous circulation, RR, relative risk