CARDIAC-PERFORMANCE ENHANCEMENT FROM DOBUTAMINE IN PATIENTS REFRACTORY TO HYPERVOLEMIC THERAPY FOR CEREBRAL VASOSPASM

The use of the beta-agonist dobutamine in combination with hypervolemi c preload enhancement of cardiac performance was analyzed in 23 patien ts who failed to respond to traditional preload enhancement following aneurysmal subarachnoid hemorrhage. The patients ranged in age from 13 to 82 years, and three had a history of cardiac disease. Each patient underwent placement of a flow-directed balloon-tipped catheter and th e following measurements were obtained during hyperdynamic therapy: pu lmonary artery wedge pressure, central venous pressure, cardiac index, stroke volume index, total peripheral resistance, and left ventricula r stroke work index (LVSWI). Mean baseline cardiac function was found to be within normal limits (LVSWI = 47.6 +/- 4.2 gm/min/sq m and cardi ac index = 3.30 +/- 0.22 liter/min/sq m). After baseline measurements were recorded, 5% albumin was infused at 300 cc/hr and dobutamine was initiated at a rate of 5 to 10 mug/kg/hr. This hyperdynamic therapy wi th dobutamine in the presence of volume loading resulted in a 52% incr ease in cardiac index, a 15% increase in LVSWI, and a 21% decrease in total peripheral resistance. The clinical reversal of ischemic symptom s due to subarachnoid hemorrhage was evident in 18 (78%) of the 23 pat ients.