This systematic review evaluated proton-pump inhibitors (PPIs) for stress ulcer prophylaxis in critically ill patients. Twelve trials with 9,533 patients were included. PPIs reduced clinically significant upper gastrointestinal bleeding (RR, 0.51; 95% CI, 0.34 to 0.76; high certainty). PPIs showed little to no effect on mortality (RR, 0.99; 95% CI, 0.93 to 1.05; low certainty). Subgroup analysis indicated possible reduced 90-day mortality in less severely ill patients (RR, 0.89; 95% CI, 0.80 to 0.98) but increased mortality in more severely ill patients (RR, 1.08; 95% CI, 0.96 to 1.20).
