Research in context
Evidence before this study
In 2008, we published a systematic review and meta-analysis of 44 randomised trials assessing the effect of a steroid in patients undergoing cardiopulmonary bypass. These trials were identified through a search of Embase, MEDLINE, Cochrane, CINAHL, and OVID between 1977 and October, 2007, using the search terms “cardiac surgery”, “cardiac surgical procedure”, “open heart surgery”, “coronary artery bypass”, “mitral valve”, “aortic valve”, “heart valve”, “cardiopulmonary bypass”, “extracorporeal circulation”, and “preoperative” and “prophylactic” in combination with generic and trade names of steroid preparations. We hand searched the reference lists from eligible trials. Trials were eligible irrespective of their primary objective or language of publication. This meta-analysis showed a non-significant reduction in mortality with the use of steroids (relative risk [RR] 0·73, 95% CI 0·45–1·18) that, if real, would be clinically important. This meta-analysis result was based on few events (n=65 deaths) and the results were inconclusive. Subsequently, the Dexamethasone for Cardiac Surgery (DECS) trial of 4494 patients did not show a reduction in mortality (RR 0·92, 0·57–1·49) or a significant reduction in the primary outcome of death, myocardial infarction, stroke, renal failure, or respiratory failure within 30 days (RR 0·83, 0·67–1·01). A subgroup analysis suggested the possibility that the steroid was beneficial in patients at higher risk of morbidity and mortality (EuroSCORE ≥5; RR 0·77, 0·61–0·98).
Added value of this study
The SIRS trial included 7500 patients with a EuroSCORE of at least 6. In the SIRS trial, methylprednisolone compared with placebo had no effect on mortality (154 deaths vs 177; RR 0·87, 0·70–1·07). An updated meta-analysis that included 14 027 patients showed no effect of steroids on mortality (RR 0·85, 0·71–1·02). SIRS identified a significant increase in myocardial injury based on raised cardiac enzymes.
Implications of all the available evidence
The collective data from all trials suggests no benefit to perioperative steroids but an increased risk of myocardial injury with routine use of steroids in patients undergoing cardiac surgery; therefore, the routine use of steroids for cardiopulmonary bypass is cautioned. Future studies should elucidate the mechanism of myocardial injury associated with the administration of steroids at the time of cardiac surgery with cardiopulmonary bypass.