HEMODYNAMIC CHANGES DURING BRIDGE OPENING IN VENO-ARTERIAL (VA) ECMO.316

Abstract

Fluctuations in cerebral hemodynamics occurred during bridge opening in VA ECMO (Pediatr Res 1995,38:124-9). To investigate the cause of these effects the bridge was opened for 2.5 and 15 s at different flow rates (500 and 50 ml/min) in 8 lambs during VA ECMO. Changes (▵) in mean arterial blood pressure (MABP), central venous pressure (CVP), left common carotic artery blood flow (Qcar), cerebral total hemoglobin concentration (ctHb, measured with near infrared spectrophotometry), intracranial pressure (ICP), flow in the ECMO circuit on the venous side between lamb and bridge (VF), and on the arterial side between bridge and lamb (AF) were measured continuously during 60 s after opening of the bridge and were compared with the mean values in the 30 s preceding the opening. During opening of the bridge changes of flow direction occurred in VF and AF, resulting in a biphasic response of MABP and Qcar and an increase in CVP, ICP, and ctHb (representing cerebral bloodvolume). Values in the table are mean ± SD. These hemodynamic changes during opening of the bridge in VA ECMO, which were independent of ECMO flow rate and opening time duration, may carry a potential risk for intracranial pathology.