A best evidence topic in cardiac surgery was written according to a structured protocol. We address whether routine pharmacological stress ulcer prophylaxis is of benefit for patients undergoing cardiac surgery. One hundred and fifty-six papers were found using the reported search, of which 10 represented the best evidence to answer the clinical question. The authors, journal, date, country of publication, patient group, study type, relevant outcomes and results of these papers were tabulated. The results show that the incidence of stress ulcers following cardiac surgery is low (0.45%), but remains associated with significant morbidity and mortality. Five of the 7 studies demonstrated suppression of acid secretion or decreased incidence of gastric complications in patients given pharmacological stress ulcer prophylaxis, with the remaining two suggesting no clinical benefit. One prospective study of 210 patients, randomized equally between a proton pump inhibitor (PPI), histamine antagonist and teprenone, found that PPIs were the most effective at reducing gastric complications after cardiac surgery, including ulcer formation and upper gastrointestinal bleeding (UGIB). However, a separate retrospective study suggested no difference in the outcomes between the use of a PPI and a histamine antagonist. Of the studies focused on histamine antagonists, one randomized control trial (RCT) showed that cimetidine can reduce surgical stress, augment the immune system and reduce the intubation time after cardiac surgery, although no direct association with UGIB was made. A second prospectively randomized study of histamine antagonists demonstrated superior pH control with famotidine and ranitidine, when compared with cimetidine. Furthermore, haematological and neurological side-effects were noted only with the use of cimetidine. A recent meta-analysis and systematic review of the literature associated gastric acid suppression with an increased risk of pneumonia. Two prospective cohort studies that examined the use of PPI in conjunction with clopidogrel in patients with coronary artery disease concluded that there was no association with an increase in major adverse cardiovascular events with the use of PPIs. We conclude that the current evidence is marginally in favour of the use of prophylactic PPIs. However, this is associated with an increased risk of hospital-acquired pneumonia.
Keywords: Stress ulcer, Gastrointestinal haemorrhage, Gastric protection, Cardiac surgery, Pneumonia