The effect of ranitidine versus proton pump inhibitors on gastric secretions: a meta-analysis of randomised control trials

Aspiration of acid into the lungs is an infrequent but potentially devastating complication of general anaesthesia. Routine practice often includes use of pharmacological agents to reduce gastric volume and increase gastric pH. The aim of this study was to compare the net benefit of proton pump inhibitors with histamine 2 blockers in a meta-analysis. Electronic databases were searched for trials that compared ranitidine vs proton pump inhibitors in their effect on volume and pH of gastric fluid aspirates. We identified nine trials of which seven were suitable for meta-analysis. Pooled outcomes suggest that premedication with ranitidine is more effective than proton pump inhibitors in reducing the volume of gastric secretions (by an average of 0.22 ml.kg(-1); 95% confidence interval 0.04-0.41) and increasing gastric pH (by an average of 0.85 pH units; 95% confidence interval -1.14 to -0.28).