Critically evaluate the strategies for prevention of gastrointestinal bleeding in the critically ill.
Answers should address more than just prevention of gastric erosions/stress ulceration.
Consideration should be given to other causes including patients with known gastro-oesophageal varices (where sclerotherapy/banding, beta-blockers and techniques to lower venous pressure, and avoidance of local trauma should be considered).
With regard to stress ulceration many strategies have been employed, and should be considered in a broad answer. General resuscitation of patients, correction of coagulopathy, early enteral feeding and avoidance of precipitants (eg. NSAIDs) in patients at risk are assumed to be beneficial (but not well studied). Prospective randomised trials have generally compared drug regimens (antacids vs sucralfate vs H2-blockers vs proton pump inhibitors). Other agents include prostaglandin analogs. Controversy surrounds the issues of widespread use of prophylactic agents, value of drugs vs placebo, nosocomial infection rates, and cost-benefit analyses.
"Critically evaluate" demands a certain degree of structure. Contrary to the college answer, banding and sclerotherapy are not usually preventative techniques. If one were to dedicate any time during this ten minute answer to varices and leaking AVMs, one may wish to be very brief about it, as the meat is clearly in gastric ulceration.
Gastrointestinal bleeding in the critically ill patient may be due to a variety of causes; these include bleeding from stress ulceration, oesophageal varices, and colonic polyps. Exacerbating causes include antiplatelet and anticoagulant medications, as well as poor perfusion of gastrointestinal mucosa in the context of shock. Given that in the ICU GI bleeding is combined with a series of other major organ dysfunction syndromes, it tends to have a castarophic mortality rate and it is important to be able to protect at-risk patients from this complication.
Evidence for the routine use of ulcer prophylaxis
Evidence to support one drug class over another
PPIs are indicated in at-risk patient in ICU who are intolerant of eneteral feeding, and who are otherwise at risk of gastrointestinal bleeding. Further research is required to discriminated between different classes of drugs in terms of efficacy, and to identify the at-risk population.
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Krag, Mette, et al. "Stress ulcer prophylaxis versus placebo or no prophylaxis in critically ill patients." Intensive care medicine 40.1 (2014): 11-22.
Madsen, Kristian Rørbæk, et al. "Guideline for Stress Ulcer Prophylaxis in the Intensive Care Unit." Danish medical journal 61.3 (2014): 1-4.
Alshamsi, Fayez, et al. "Efficacy and safety of proton pump inhibitors for stress ulcer prophylaxis in critically ill patients: a systematic review and meta-analysis of randomized trials." Critical Care 20.1 (2016): 120.
Barletta, Jeffrey F., et al. "Stress ulcer prophylaxis." Critical care medicine44.7 (2016): 1395-1405.