Influence of timing of intraaortic balloon placement in cardiac surgical patients

Abstract

The study objective was to evaluate the association between timing of intraaortic balloon pump insertion and outcomes in patients undergoing cardiac surgery. All patients aged 18 years or more who underwent coronary artery bypass surgery, cardiac valve surgery, or thoracic aortic surgery between January 2002 and December 2007 were included. Data were obtained from cardiac surgery and intensive care databases. Patients were categorized as receiving a preoperative, intraoperative, or postoperative intraaortic balloon pump and compared with a reference group who did not receive an intraaortic balloon pump. Summary and descriptive statistics were used to compare the groups. Logistic regression was used to model in-hospital mortality, and survival methods were used to model time to event data, such as length of stay. There were 7440 patients included over a 6-year period, of whom 217 (2.9%) received a preoperative intraaortic balloon pump, 184 (2.4%) received an intraoperative intraaortic balloon pump, and 42 (0.56%) received a postoperative intraaortic balloon pump. Logistic European System for Cardiac Operative Risk Evaluation-derived predicted risk of death was higher across all intraaortic balloon pump groups compared with the group with no intraaortic balloon pump. Observed in-hospital mortality was significantly lower in the preoperative group (10%) and the group with no intraaortic balloon pump (0.8%) compared with the intraoperative (16%) and postoperative (29%) groups. Risk-adjusted mortality was also lower in the preoperative group. This study comparing outcomes in patients undergoing cardiac surgical procedures with timing of intraaortic balloon pump placement revealed that the use of preoperative intraaortic balloon pumps was associated with a strong trend toward reduction in in-hospital mortality despite a higher predicted mortality in this group. The study provides support to the growing body of literature advocating preoperative use of intraaortic balloon pumps in carefully selected patients.