Survival Time of ECMO Circuits On and Off Bleeding Protocol: Is there a Higher Risk of Circuit Clotting?

Abstract

Purpose: Bleeding is a dreaded complication of extracorporeal membrane oxygenation (ECMO). At our institution, we use a bleeding protocol (BP) with or without ε-amino caproic acid (ACA) for certain prophylactic or therapeutic indications. Subjectively, we have felt that placing a child on bleeding protocol shortens the circuit life because of clot formation. In this study, we evaluated the impact of BP with and without ACA on the survival time of the ECMO circuit.

Methods: A retrospective analysis of all ECMO patients treated in our institution from 2000 to 2008 was performed. An event was defined as a change of the ECMO circuit for thrombosis. The times until occurrence of an event were noted for children off (standard) or on bleeding protocol (BP) and ACA (BP+ACA). Survival curves were generated for each of these study groups and compared using the log rank test.

Results: A total of 164 patients were treated with ECMO during the study period. 32 events were noted in the standard, 20 in the BP, and 25 in the BP+ACA group. Mean survival time of the circuit was 10.5±3.8 days for the standard, 8.6±3.4 days for the BP, and 9.9±4.6 days for BP+ACA protocols. The corresponding Kaplan-Meier survival curves are shown. The log rank test showed no significant differences between groups (standard vs. BP p=0.12; standard vs. BP+ACA p=0.92).

Conclusions: We found no evidence that instituting a bleeding protocol with or without aminocaproic acid shortens circuit times. Clotting of the ECMO unit should not be a major concern when placing a patient on a bleeding protocol.

Key words

extracorporeal membrane oxygenation - bleeding protocol - thrombosis - circuit life

References

• 1 Extracorporeal Life Support Organization (ELSO) . General Guidelines for all ECLS Cases.  Available online at: http://www.elso.med.umich.edu/WordForms/ELSO%20Guidelines%20General%20All%20ECLS%20Version1.1.pdf last accessed 16 August 2010
• 2 Peek GJ, Firmin RK. The inflammatory and coagulative response to prolonged extracorporeal membrane oxygenation.  ASAIO J. 1999;  45 250-263
• 3 Oliver WC. Anticoagulation and coagulation management for ECMO.  Semin Cardiothorac Vasc Anesth. 2009;  13 154-175
• 4 Wilson JM, Bower LK, Fackler JC. et al . Aminocaproic acid decreases the incidence of intracranial hemorrhage and other hemorrhagic complications of ECMO.  J Pediatr Surg. 1993;  28 536-540
• 5 Downard CD, Betit P, Chang RW. et al . Impact of AMICAR on hemorrhagic complications of ECMO: a ten-year review.  J Pediatr Surg. 2003;  38 1212-1216
• 6 Sell LL, Cullen ML, Whittlesey GC. et al . Hemorrhagic complications during extracorporeal membrane oxygenation: prevention and treatment.  J Pediatr Surg. 1986;  21 1087-1091
• 7 Reed RC, Rutledge JC. Laboratory and clinical predictors of thrombosis and hemorrhage in 29 pediatric ECMO nonsurvivors.  Pediatr Dev Pathol. 2010 Jan 19. [Epub ahead of print] PMID: 20085498
• 8 Chalwin RP, Tiruvoipati R, Peek GJ. Fatal thrombosis with activated factor VII in a paediatric patient on extracorporeal membrane oxygenation.  Eur J Cardiothorac Surg. 2008;  34 685-686
• 9 Graves DF, Chernin JM, Kurusz M. et al . Anticoagulation practices during neonatal extracorporeal membrane oxygenation: survey results.  Perfusion. 1996;  11 461-466
• 10 Baird CW, Zurakowski D, Robinson B. et al . Anticoagulation and pediatric extracorporeal membrane oxygenation: impact of activated clotting time and heparin dose on survival.  Ann Thorac Surg. 2007;  83 912-919

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