Hemodynamic tracings during weaning from cardiopulmonary bypass

During weaning from cardiopulmonary bypass, venous drainage to the pump is reduced, the heart gradually fills, and the arterial blood pressure (ABP) tracing becomes pulsatile.
(A) The tracing shows the beginning of the weaning process, with the patient requiring atrial pacing at a rate of 86 for bradycardia, an ABP of 80/71, and central venous pressure (CVP) of 11.
(B) With further reduction of venous drainage to the pump, the ABP tracing becomes more pulsatile as additional cardiac filling generates a larger stroke volume and pulse pressure. The tracing shows this phase of weaning from bypass, with ABP 103/62 and CVP 12. Note that atrial pacing is no longer required, because the patient is in normal sinus rhythm at a rate of 77.