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

Objective.To determine if the measurement of gastricintramucosal pH (pHi) is useful for evaluation of circulatory status ofcritically ill pediatric patients. Design.Prospective clinicalstudy. Setting.General intensive care unit in a universityhospital. Patients.Seven pediatric patients (mean age: 2 y.o.);six post-cardiac surgery, one receiving barbiturate therapy.Interventions.Tonometric catheters were placed via nasogastricapproach. pHi was measured after confirmation of the catheter positionby X-ray. Measurements and main results.Saturation of venousblood oxygen (SvO₂), arterial keton body ratio (AKBR), serumlactate level and pHi were evaluated simultaneously. No patientssurvived with pHi below 7.22; pHi above 7.11 significantly correlatedwith SvO₂ values (r= 0.814, p< 0.001);pHi below 7.11 did not show any significant correlation withSvO₂. Whereas SvO₂ values of under 40% weredistributed in the pHi range from 7.11 to 7.19, pHi below 7.11 occurredwhen SvO₂ values were more than 40%. AKBR and serumlactate level did not correlate with pHi. Conclusion.pHi can bea useful parameter for evaluating the circulatory status of criticallyill pediatric patients; it allows reliable evaluation of splanchnic andperipheral perfusion.