Does splanchnic ischemia occur in isolated neurotrauma? A prospective observational study

Objective: To characterize the incidence and severity of splanchnic ischemia, as defined by gastric tonometry, in patients with isolated severe head injury and to examine the relationship between cerebral hemodynamics and splanchnic ischemia, Design: Prospective observational study. Setting: Neurosurgical intensive care unit in a tertiary referral center. Patients: Ten patients with severe neurotrauma. Interventions: None. Measurements and Main Results: The mean arterial pressure, intracranial pressure, and gastric mucosal Pco(2) measurements were recorded at 15-min intervals. Intramucosal pH was calculated every 3 hrs. All patients received stress ulcer prophylaxis. Nine patients received noradrenaline infusions to maintain a target cerebral perfusion pressure of 70 mm Hg. The mean baseline gastric mucosal Pco(2) and intramucosal pH were 38 +/- 10 torr and 7.38 +/- 0.1 pH units, respectively. Nine patients manifested low intramucosal pH during the study period. Gastric mucosal Pco(2) values ranged from 36 to 132 torr. Intramucosal pH measurements ranged from 6.9 to 7.47. The mucosal gap ranged from -12 to +93 torr (mean +/- SD, 17 +/- 17 torr). The pH gap ranged from -0.1 to +0.54 pH units (mean +/- SD, 0.14 +/- 0.11 pH units). There was no statistically significant relationship between cerebral hemodynamics, the use of inotropes, and gastric mucosal Pco(2), or intramucosal pH. Conclusions: Splanchnic ischemia (intramucosal pH, <7.3) occurs commonly in isolated neurotrauma, with a statistically nonsignificant trend toward development of mucosal ischemia with decreased cerebral perfusion.