Research
The relationship between inotrope exposure, six-hour postoperative physiological variables, hospital mortality and renal dysfunction in patients undergoing cardiac surgery
1 Division of Critical Care, McGill University Health Centre, 687 Pine Avenue West, Montreal, QC, H3A 1A1, Canada
2 Division of Cardiac Surgery, McGill University Health Centre, 687 Pine Avenue West, Montreal, QC, H3A 1A1, Canada
3 McGill University Faculty of Medicine, 845 Sherbrooke Street West, Montreal, QC, H3A 2T5, Canada
4 Respiratory Epidemiology and Clinical Research Unit, Montreal Chest Institute, McGill University Health Centre, 3650 St-Urbain, Montreal, QC, H2X 2P4, Canada
5 Department of Critical Care, SMBD-Jewish General Hospital, McGill University, 845 Sherbrooke Street West, Montreal, QC, H3A 2T5, Canada
Critical Care 2011, 15:R162 doi:10.1186/cc10302
See related commentary by Singer and Brealey, http://ccforum.com/content/15/4/179 and related letter by Hajjar et al., http://ccforum.com/content/15/5/444
Published: 7 July 2011Abstract
Introduction
Acute haemodynamic complications are common after cardiac surgery and optimal perioperative use of inotropic agents, typically guided by haemodynamic variables, remains controversial. The aim of this study was to examine the relationship of inotrope use to hospital mortality and renal dysfunction.
Material and methods
A retrospective cohort study of 1,326 cardiac surgery patients was carried out at two university-affiliated ICUs. Multivariable logistic regression analysis and propensity matching were performed to evaluate whether inotrope exposure was independently associated with mortality and renal dysfunction.
Results
Patients exposed to inotropes had a higher mortality rate than those not exposed. After adjusting for differences in Parsonnet score, left ventricular ejection fraction, perioperative intraaortic balloon pump use, bypass time, reoperation and cardiac index, inotrope exposure appeared to be independently associated with increased hospital mortality (adjusted odds ratio (OR) 2.3, 95% confidence interval (95% CI) 1.2 to 4.5) and renal dysfunction (adjusted OR 2.7, 95% CI 1.5 to 4.6). A propensity score-matched analysis similarly demonstrated that death and renal dysfunction were significantly more likely to occur in patients exposed to inotropes (P = 0.01).
Conclusions
Postoperative inotrope exposure was independently associated with worse outcomes in this cohort study. Further research is needed to better elucidate the appropriate use of inotropes in cardiac surgery.



