[Stress bleeding. 2. Prophylaxis]

Preventive strategies aim to reduce gastric acidity (H2-antagonists, antacids), to strengthen mucosal defence mechanisms (sucralfate, antacids, pirenzepine) and to normalize gastric mucosal microcirculation (sucralfate, pirenzepine). Thus, the most important prophylactic measure is an optimized emergency and ICU regime aiming to improve oxygenation and microcirculation. All specific drugs used for stress ulcer prophylaxis have been shown to be effective in prospective controlled studies. Furthermore, pirenzepine has been found to be superior to H2-antagonists, at least in neurosurgical patients. Insufficient or no data exist to support the use of prostaglandins or omeprazole for stress ulcer prophylaxis. The most important adverse effect of stress ulcer prophylaxis is nosocomial pneumonia due to gastric alkalinization. This may occur in long-term ventilated patients with a gastric pH > 4 and may account for up to 50% of all nosocomial pneumonias in certain groups of patients. Mortality is not influenced by antacids or H2-antagonists, while sucralfate has been shown to reduce mortality, most probably by inhibition of bacterial translocation.