Gastric colonization and pneumonia in intubated critically ill patients receiving stress ulcer prophylaxis: a...

To study the effects of pharmacologically increasing gastric pH on gastric colonization and the development of pneumonia in intubated critically ill patients.

Randomized, controlled trial.

Medical ICU in a university hospital.

Thirty-four tracheotomized patients with tetanus.

Sixteen patients received iv ranitidine to increase gastric pH greater than 4 (ranitidine group), while 18 patients received no prophylaxis for upper gastrointestinal bleeding (control group).

Mean gastric pH was higher in the ranitidine group (median 4.7, range 3.6 to 6.1) than in the control group (median 2.1, range 1.2 to 4.9; p less than .05). Gastric colonization occurred in 15 (94%) of 16 patients who received ranitidine, 2 days (median; range 1 to 5) after intubation; gastric colonization also occurred in all control patients (median 4 days, range 1 to 9; p less than .05). Pneumonia occurred in 13 (81%) of 16 patients who received ranitidine, 3 days (median, range 1 to 5) after intubation and in nine (50%) of 18 control patients (p less than .01) 5 days after tracheal intubation (median, range 3 to 14; p less than .01). Prior gastric colonization by the pathogen that caused pneumonia was demonstrable in nine (56%) of 16 patients who received ranitidine vs. eight (44%) of 18 control patients (p greater than .05). The risk for developing pneumonia in the ranitidine-treated group was highest in the first 4 days after tracheal intubation. There was no difference in the frequency of upper gastrointestinal hemorrhage in the two groups.

Pharmacologically increasing gastric pH increases the risk for developing pneumonia in intubated critically ill patients. The pneumonia occurs earlier than in untreated control patients.