Reducing gastric secretions-a role for histamine 2 antagonists or proton pump inhibitors in malignant bowel obstruction?

Inoperable bowel obstructions are not uncommon in advanced cancer and are associated with a very poor prognosis. Symptom control includes reducing the frequency of vomiting by prescription of antisecretory medications. The most commonly used agents for this are either hyoscine butylbromide or octreotide. Either histamine 2 antagonists or proton pump inhibitors are sometimes recommended as adjuvants to reduce gastric secretions. The aim of this study was to examine the effects of histamine 2 antagonists and proton pump inhibitors and to objectively compare the effects of one agent over another. Previously, electronic databases were searched for trials that compared ranitidine versus proton pump inhibitors in their effect on volume of gastric aspirates. Seven trials were included in a meta-analysis. Pooled outcomes suggest that both proton pump inhibitors and ranitidine reduce gastric volumes, but the most superior agent is ranitidine, which reduces the volume of gastric secretions by an average of 0.22 ml.kg(-1); 95% confidence interval 0.04 to 0.41. Based on well-conducted studies, objective evidence exists that confirms ranitidine will decrease the volume of gastric aspirates. This forms a sound basis from which to develop further research aimed at improving the care of people with malignant bowel obstructions.