Validity of gastric intramucosal pH (pHi) for circulatory evaluation in pediatric patients

Abstract

Objective: To determine if the measurement of gastric intramucosal pH (pHi) is useful for evaluation of circulatory status of critically ill pediatric patients.

Design: Prospective clinical study.

Setting: General intensive care unit in a university hospital.

Patients: Seven pediatric patients (mean age: 2 y.o.); six post-cardiac surgery, one receiving barbiturate therapy.

Interventions: Tonometric catheters were placed via nasogastric approach. pHi was measured after confirmation of the catheter position by X-ray.

Measurements and main results: Saturation of venous blood oxygen (SvO2), arterial keton body ratio (AKBR), serum lactate level and pHi were evaluated simultaneously. No patients survived with pHi below 7.22; pHi above 7.11 significantly correlated with SvO2 values (r = 0.814, p < 0.001); pHi below 7.11 did not show any significant correlation with SvO2. Whereas SvO2 values of under 40% were distributed in the pHi range from 7.11 to 7.19, pHi below 7.11 occurred when SvO2 values were more than 40%. AKBR and serum lactate level did not correlate with pHi.

Conclusion: pHi can be a useful parameter for evaluating the circulatory status of critically ill pediatric patients; it allows reliable evaluation of splanchnic and peripheral perfusion.