Gastrointestinal (GI) prophylaxis in the intensive care unit (ICU) is important in the prevention of stress gastritis. The incidence of clinically significant bleeding in critically ill patients is 2% to 15%. However, it is important to understand the actual indications for prophylaxis. Most experienced clinicians feel it should be limited to patients at high risk for stress-related mucosal diseases, which include the following conditions: mechanical ventilation longer than 48 hours; coagulopathy; endoscopic or radiographic diagnosis of peptic ulcer or gastritis; history of an upper GI bleed less than 6 weeks prior to admission; significant burns (greater than 15% of total body surface area); traumatic brain injury; and large doses of glucocorticoids (e.g., >50mg hydrocortisone/day).

Prophylactic medications to prevent stress gastritis include antacids, sucralfate, histamine-2 receptor antagonists (H2-blockers), and proton pump inhibitors (PPIs). Cook et al., in a multicenter randomized double-blind controlled trial, demonstrated that H2-blockers (ranitidine) compared with sucralfate decreased clinically significant bleeding with no difference in ventilator-associated pneumonia. To date there are no studies that have prospectively evaluated the ability of intravenous PPIs to reduce clinically significant bleeding in high-risk critically ill patients; however, PPIs have been shown to raise and maintain an elevated gastric pH. When deciding between H2-blockers and PPIs, side effects and cost should be considered. If the patient requires intravenous medications, H2-blockers are the most cost-effective. However, if the patient is able to tolerate oral medications, PPIs are a good choice given their ability to maintain gastric pH for a sustained period of time. The overall need for prophylaxis should be assessed when patients are able to meet their nutritional requirements by mouth.