Does the use of non-steroidal anti-inflammatory drugs after cardiac surgery increase the risk of renal failure?

A best evidence topic in cardiac surgery was written according to a structured protocol. The question addressed was whether the use of non-steroidal anti-inflammatory drugs (NSAIDs) for pain relief post-cardiac surgery increases the risk of renal failure. Altogether 53 papers were found using the reported search, of which 11 represented the best evidence to answer the clinical question. The authors, journal, date and country of publication, patient group studied, study type, relevant outcomes and results of these papers are tabulated. We identified 11 studies, comprising one meta-analysis, seven randomised controlled trials (RCTs), and three retrospective studies. The meta-analysis of 1065 patients across 20 RCTs established that the risk of renal failure was not significantly higher with perioperative NSAID usage [odds ratio (OR) 0.95, 95% confidence interval (CI) 0.37-2.46]. Furthermore, there was no statistically significant difference in serum creatinine levels between NSAID and control groups. Six RCTs agreed that postoperative NSAID therapy was not associated with an elevation in serum creatinine levels suggestive of renal failure. One of these RCTs was conducted in a paediatric population undergoing congenital heart surgery, and achieved equivalent results. Another large RCT found a non-significant increase in the incidence of renal failure/dysfunction in patients receiving the cyclo-oxygenase 2 (COX-2) selective drugs parecoxib and valdecoxib vs. placebo (placebo vs. parecoxib and valdecoxib: relative risk (RR) 2.4, 95% CI 0.6-9.2, P=0.20) whilst highlighting the potential adverse vascular effects of this drug class. In contrast, one RCT assessing these COX-2 inhibitors detected a significant increase in the incidence of oliguria in this group compared to controls (parecoxib/valdecoxib: 14.5%, controls: 9.9%, P=0.187) as well as renal dysfunction (parecoxib/valdecoxib: 1.9%, controls: 0%, P=0.184). Three retrospective studies within paediatric populations, including one cohort study and two chart reviews, found various parameters of renal function, such as serum creatinine and blood urea nitrogen, to be similar between ketorolac and control groups. We conclude that NSAIDs are not associated with an increased risk of renal failure after cardiac surgery when administered at optimal 'renal' doses, within early postoperative settings, to patients at low-risk of renal dysfunction in whom NSAIDs are not contraindicated.