Intra-aortic balloon counterpulsation: Outcome in cardiac surgical patients

Objective: To identify the major determinants of survival and nonsurvival for patients in need of intra-aortic balloon pump (IABP) support after cardiac surgery and to define the role of ventilator-associated pneumonia. Design: Retrospective study. Setting: University and general hospital. Participants: A total of 105 consecutive patients undergoing cardiac surgery requiring IABP support and prolonged mechanical ventilation for > 24 hours. intervention: All patients were assigned into 1 of 2 groups: survival (n = 69) and nonsurvival (n = 36). Measurements and Main Results: Differences between the survival and nonsurvival groups were tested with the Student's t-test, chi-square test, and frequency analysis. The overall survival rate was 65.7%. Nonsurvivors (34.3%) had higher rates of acute myocardial infarction (27.7% v 4.3%; p < 0.002), Canadian Cardiovascular Society functional class III and IV (44.4% and 13.8%; p < 0.001), and depressed left ventricular ejection fraction (31.3 +/- 6.4% v 42.4 +/- 7.2%; p < 0.001). The nonsurvival group had longer duration of cardio-pulmonary bypass (165 +/- 74.3 minutes v 135 +/- 36 minutes; p < 0.006) and aortic occlusion (81.8 +/- 9 minutes v 68.6 +/- 25.7 minutes; p < 0.004). In the nonsurvival group, 21 patients were not weaned from the IABP, and 15 patients were weaned from the IABP but died from renal failure (26.6%), multiorgan failure (13.3%), infection, and respiratory failure (66.6%). In the nonsurvival group, mechanical ventilation time was longer in patients weaned from the IABP. Conclusion: These data suggest that for patients not weaned from the IABP, the major determinants of death are low cardiac output (33.3%) and multiorgan failure (47.6%). Patients with a left ventricular ejection fraction of < 30% have a poorer outcome. In patients weaned from the IABP, ventilator-associated pneumonia (66.6%) was the major cause of death. Copyright (C) 2001 by WB. Saunders Company.