Lessons learned from the first clinical implants of the DeBakey ventricular assist device axial pump: a single center report.

BACKGROUND: The bridge to transplantation with pulsatile mechanical assist devices became a standard procedure for patients deteriorating on the waiting list. Recently, continuous flow axial impeller pumps were introduced to clinical application offering new advantages. METHODS: From November 1998 till September 2000, 6 male patients (mean age 53 plus or minus 11 years) with end-stage left heart failure were implanted with a DeBakey ventricular assist device (VAD) axial-flow pump for bridge to transplantation. RESULTS: Three patients were successfully transplanted after 74, 115, and 117 days, respectively. Two other patients died after 25 and 133 days. One patient is still on the device after 108 days. Because of modification of the implantation technique after the first 2 patients, mean pump-flow within the first 3 weeks was increased from 4.3 +/- 0.6 L/min to 6.7 +/- 0.3 L/min. Patients were put on regular bicycle-ergometer training and improved their exercise capacities up to a mean maximum oxygen consumption of 20.2 mL/kg/min. CONCLUSIONS: Initial implants of the DeBakey VAD demonstrated support properties comparable to pulsatile pumps but without significant restrictions for extended use.

Jugular venous bulb oxygen saturation depends on blood pressure during cardiopulmonary bypass.

BACKGROUND: Central nervous system dysfunction after cardiopulmonary bypass is frequent and can be caused by inadequate cerebral perfusion and oxygenation. METHODS: To test the effectiveness of cerebral autoregulation during cardiopulmonary bypass, we induced changes in the cerebral perfusion pressure by administering phenylephrine during moderate (29 degrees C) hypothermia. Using the Fick principle, we calculated relative changes in cerebral blood flow from changes in the jugular venous bulb oxygen saturation. RESULTS: Increasing the cerebral perfusion pressure (from 47 +/- 8.2 to 93 +/- 16 mm Hg) induced increases in the jugular venous bulb oxygen saturation by 4.9% and a calculated increase in the cerebral blood flow by 19.9%, strongly suggesting impaired cerebral autoregulation. CONCLUSIONS: Because cerebral autoregulation is impaired during cardiopulmonary bypass, phenylephrine is effective in increasing the cerebral blood flow and may contribute to the prevention of postoperative neurologic dysfunction, especially in patients who have a low jugular venous bulb oxygen saturation.