Early fnteral nutrition may have detrimental effects in patients with gastrointestinal hypoperfusion

Despite widespread acceptance that patients sustaining major trauma benefit from early enterai nutrition, relatively little is known regarding the safety and tolerance of enterai nutrition in the most severely injured patients. Traumatic shock results in disproportionate splanchnic vasoconstriction which may cause persistent intestinal ischémie injury despite adequate systemic resuscitation. Gastrointestinal tonometry is a relatively noninvasive method that appears capable of identifying intestinal hypoperfusion that may result in critical intestinal ischemia. This study was designed to test the hypothesis that during intestinal hypoperfusion, the provision of enterai nutrients may increase the oxygen demand beyond that which can be satisfied by available delivery, thus causing critical gut ischemia. In a prospective manner, six patients (30+6 years) received gastric tonometers and were subjected to a standard early enterai feeding protocol within 24 hours of admission. Severely injured trauma patients, who required aggressive shock resuscitation and were thus likely to experience intestinal hypoperfusion, were compared to control trauma patients, who were not subjected to a shock resuscitation protocol. Intramucosal gastric pH was determined every 12 hours in all patients. Intramucosal gastric pH decreased (p<0.05) over time with enterai nutrition in the severely injured patients and 1 patient developed nonocclusive small bowel necrosis. In contrast, intramucosal gastric pH did not change over time during the provision of early enterai nutrition in the control patients. These results suggest that the provision of enterai nutrients in severely injured trauma patients should proceed with caution to ensure that intestinal perfusion is adequate to allow nutrient metabolism. Further studies examining the use of gastric tonomelry as an objective monitoring tool of gastrointestinal lolerance to enterai nutrition are warranted.