COMPARISON OF THE USE OF A PROPOFOL INFUSION IN CARDIAC SURGICAL PATIENTS WITH NORMAL AND LOW CARDIAC-OUTPUT STATES

Objectives:This study compared the hemodynamic effects of a propofol i nfusion with fentanyl analgesia in patients undergoing cardiac surgery with normal and low cardiac output states. Low cardiac output was def ined as a cardiac index less than 2.5 L/min/m(2) with a minimum pulmon ary capillary wedge pressure of 7 mmHg. Design: A prospective and open study. Setting: A single center cardiothoracic unit within a teaching hospital. Participants: Patients were assigned to group P, poor cardi ac output or group N, normal cardiac output, after thermodilution pulm onary artery catheter assessments. Interventions: Both groups received a propofol infusion, 8 mg/kg/hr, until induction of anesthesia, follo wed by 4 mg/kg/hr until the intensive care unit. Fentanyl, 15 mu g/kg, and pancuronium, 0.15 mg/kg, were administered after induction. The l ungs were ventilated with oxygen. Measurements and Main Results: Hemod ynamic assessments were repeated at intervals until cardiopulmonary by pass. Changes within and between groups were compared using t tests on percentage change from baseline. Group N had significantly greater de creases in cardiac index, stroke volume, and left ventricular stroke w ork index than group P. There were comparable decreases in mean arteri al pressure on induction of anesthesia, 14% and 8% in group N and grou p P, respectively. In both groups, right ventricular ejection fraction was unchanged. Conclusions: The use of a propofol infusion for induct ion and maintenance of anesthesia in patients with low cardiac output states undergoing cardiac surgery is not contraindicated. Copyright (C ) 1995 by W.B. Saunders Company