REVIEW฀ARTICLE฀ Stress฀ulcer฀prophylaxis฀in฀critically฀ill฀patients... 107 Introduction Stress ulcer‑related gastrointes‑ tinal (GI) bleeding was irst described in1969. 1 Subsequently, a large case series that described this condition in further details was published. 2,3 Over the last few decades, the use of stress ulcer prophylaxis (SUP) has been a controversial topic in the care of critically ill patients. here are still questions concerning diagnosis, risk factors for bleeding, and need for and choice of prophylactic agents. he aim of this review was to explore cur‑ rent controversies and questions. Do we need to use SUP in critically ill patients? Which patients will beneit from SUP? Are there diferences in the eicacy of various drug classes? Definitions Several deinitions have been used to describe diferent forms of stress ulcer bleed‑ ing; we present those that are used in the pub‑ lished literature. Occult bleeding is usually de‑ ined as a positive guaiac test on fecal sample without overt GI bleeding; overt bleeding is de‑ ined as hematemesis, cofee ground emesis, me‑ lena, or bloody nasogastric aspirate; clinically im‑ portant bleeding (CIB) is usually deined as overt bleeding plus one of the following 4 features in the absence of other causes: a spontaneous drop of systolic or diastolic blood pressure of 20 mmHg or more within 24 hours of upper GI bleeding, an orthostatic increase in pulse rate of 20 beats per minute and a decrease in systolic blood pres‑ sure of 10 mmHg, a decrease in hemoglobin of at least 2 g/dl (20 g/l) in 24 hours or transfusion of 2 U packed red blood cells within 24 hours of bleeding. 3 Incidence and clinical implications of gastrointestinal bleeding in critically ill patients here is a varia‑ tion in the estimates of incidence due to a lack of standardization of the deinition of stress ulcer‑ ‑related GI bleeding and the heterogeneity of risk of bleeding among patients. he incidence of “mu‑ cosal injury” based on endoscopic studies was as high as 75%–100%, frequently observed within 24 hours of admission to the intensive care unit (ICU). 2,4 Occult bleeding incidence ranges from 15% to 50%. 5 he incidence of overt bleeding is 5% to 25% among critically ill patients who do not receive prophylaxis. 6,7 However, overt bleeding does not necessarily translate into CIB. 8 In the 2 large prospective cohort studies, the incidence of CIB was observed to be 1.5% and 3.5%. 3,9 he mor‑ tality in those patients was signiicantly higher when compared with patients who did not bleed (48.5% vs. 9.1%). 9 he incidence of bleeding was also recorded in other populations. In a retrospective review of REVIEW ARTICLE Stress ulcer prophylaxis in critically ill patients: review of the evidence Waleed Alhazzani 1 , Mohammed Alshahrani 2 , Paul Moayyedi 1,3 , Roman Jaeschke 1,3 1 Department of Medicine, McMaster University, Hamilton, Canada 2 Department of Critical Care and Emergency Medicine, King Fahad Hospital, Dammam University, Saudi Arabia 3 Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, Canada Correspondence to: Waleed Alhazzani, MD, FRCPC, Department of Medicine, McMaster University, 1200 Main Street West, Hamilton, Ontario, Canada, L8N 3Z5, phone: +1‑905‑902‑2572, fax: +1‑905‑521‑6068, e‑mail: waleed.al‑ ‑hazzani@medportal.ca Received: December 2, 2011. Revision accepted: January 25, 2012. Published online: February 17, 2012. Conflict of interest: P. Moayyedi has been a member of the advisory board for AstraZeneca and Johnson & Johnson and has received speaker fees from AstraZeneca, Abbott, Nycomed, and Johnson & Johnson. He has received research support from AstraZeneca and Axcan. His chair is funded in part by an unrestricted donation to McMaster University from AstraZeneca. Pol Arch Med Wewn. 2012; 122 (3): 107‑114 Copyright by Medycyna Praktyczna, Kraków 2012 AbsTRACT Critically ill patients are at risk of developing stress ulcers in the upper digestive tract. Multiple risk factors have been associated with the development of this condition, with variable risk of association. Decades of research have suggested the benefit of using pharmacologic prophylaxis to reduce the incidence of clinically important upper gastrointestinal bleeding, with no reduction in overall mortality. It has been the standard of care to provide prophylaxis to patients at risk. Options for prophylaxis include: proton‑pump inhibitors, histamine 2 ‑receptor antagonists, or sucralfate. The choice of prophylaxis depends on multiple factors including the presence of risk factors, risk for nosocomial pneumonia, and possibly cost. KEy WoRDs acid suppression, critically ill patients, gastrointestinal bleeding prophylaxis, stress ulcer bleeding