Acute hemodynamic, respiratory and metabolic alterations after blood contact with a volume priming and extracorporeal life support circuit: an experimental study.

OBJECTIVE To investigate the hemodynamic, respiratory and metabolic impact of blood contact with a priming volume and extracorporeal membrane oxygenation circuit, before the initiation of oxygenation and ventilation METHODS Five animals were instrumented and submitted to extracorporeal membrane oxygenation. Data were collected at the baseline and 30 minutes after starting extracorporeal circulation, without membrane ventilatory (sweeper) flow. RESULTS After starting extracorporeal membrane oxygenation, there was a non-significant elevation in pulmonary vascular resistance from 235 (178,303) to 379 (353,508) dyn.seg.(cm5)-1 (P=0.065), associated with an elevation in the alveolar arterial oxygen gradient from 235 (178,303) to 379 (353,508) mmHg (P=0.063). We also observed a reduction in the left ventricle stroke work from 102 (94,105) to 78 (71,87) (mL.mmHg)/beat (P=0.064), in addition to a reduction in cardiac output from 7.2 (6.8,7.6) to 5.9 (5.8,6.3) L/min (P=0.188). The right ventricle stroke work was counterbalanced between the pulmonary vascular resistance increment and the cardiac output reduction, maintaining a similar value. CONCLUSIONS We presented an experimental model that is feasible and safe. Blood contact with the priming volume and extracorporeal membrane oxygenation circuit resulted in non-significant systemic or metabolic changes.