GASTRIC TONOMETRY SUPPLEMENTS INFORMATION PROVIDED BY SYSTEMIC INDICATORS OF OXYGEN-TRANSPORT

Hypothesis. Assessment of splanchnic perfusion by gastric intramucosal pH (pHi) adds to the information provided by systemic indicators of o xygen transport. Setting. University Hospital level I trauma center. D esign. Prospective study in 20 critically ill trauma patients comparin g pHi with base deficit, lactate, oxygen delivery, and oxygen consumpt ion (indexed to body surface area), mixed venous oxygen saturation (SV O2), oxygen utilization coefficient, and arterial pH. All measurements were obtained at admission, 1, 2, 4, 8, 16, and 24 hours, or at death . Main Outcome Measures. Correlation of pHi with the measured systemic variables, prediction of organ dysfunction, development of multiple o rgan dysfunction syndrome, and mortality. Results. There was a poor co rrelation between pHi and the systemic hemodynamic and oxygen transpor t variables. Patients with a low pHi (<7.32) on admission who did not correct within the initial 24 hours had a higher mortality (50% vs. 0. 0%, p = 0.03) and incidence of organ dysfunction (2.6 organs/patient v s. 0.62 organs/patient, p = 0.02) than those who did. Using logistic r egression analysis, only pHi, base deficit, and SVO2 were significantl y associated with mortality during the study period. At 24 hours, only pHi was different between patients who developed multiple organ dysfu nction syndrome and those who did not. There was a threshold value for pHi (7.10) which identified those patients who would go on to develop multiple organ dysfunction syndrome. Conclusions. Uncorrected splanch nic malperfusion is associated with a higher incidence of organ dysfun ction and mortality. Gastric tonometry supplements information provide d by systemic indicators of oxygen transport during resuscitation of c ritically ill trauma patients.