Effects of feeding on gastric tonometric measurements in critically ill children.
OBJECTIVE
To determine the effect of gastric feeding on the measurement of gastric intramucosal PCO2 (PiCO2) and its derived gastric intramucosal PCO2-arterial PCO2 difference (PiCO2-PaCO2 difference) and gastric intramucosal pH (pHi) in a group of critically ill children using recirculating gas tonometry.


METHODS
Prospective clinical pilot study.


METHODS
Sixteen bed pediatric intensive care unit.


METHODS
Ten mechanically ventilated and hemodynamically stable children (median age, 20.1 months [interquartile range (IQR), 9.7-47.6 months] and median weight, 10.2 kg [IQR, 10-16.5 kg]).


METHODS
A 7-French recirculating gas tonometer was placed in the stomach via the orogastric route.


METHODS
In each patient, baseline fasted/unfed PiCO2, PiCO2-PaCO2 difference, and pHi were determined hourly over a 5-hr period. Gastric feeding was then reestablished (3 mL/kg/hr) within a median time of 3 hrs and a further 5 hourly measurements were determined. Concurrent arterial blood gas and lactate measurements were taken. Blood pressure and heart rate was monitored throughout.


RESULTS
Hemodynamic parameters remained stable throughout the study period. When compared with the unfed/fasting state, PiCO2 measurements and PiCO2-PaCO2 difference were consistently lower and pHi values higher than when the patients were fed (two-way analysis of variance for repeated measures: all p <.001 between groups). Measurements did not vary over time.


CONCLUSIONS
In our patient group, gastric feeding decreased the PiCO2 and PiCO2-PaCO2 difference and increased pHi compared with the unfed state. These findings are in contrast to those found in adult studies.
Thorburn
Kentigern
K
Department of Paediatric Intensive Care, Royal Liverpool Children's Hospital-Alder Hey, UK.
Durward
Andrew
A
Tibby
Shane M
SM
Murdoch
Ian A
IA
D001784:Blood Gas Analysis; D002245:Carbon Dioxide / Q000032:analysis / Q000378:metabolism*; D002675:Child, Preschool; D003422:Critical Care / Q000379:methods; D016638:Critical Illness / Q000628:therapy*; D004750:Enteral Nutrition / Q000379:methods*; D005260:Female; D005746:Gastric Emptying / Q000502:physiology*; D005753:Gastric Mucosa / Q000098:blood supply; D005774:Gastrostomy; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007223:Infant; D015278:Intensive Care Units, Pediatric; D008297:Male; D008365:Manometry / Q000379:methods; D008991:Monitoring, Physiologic / Q000295:instrumentation*; D015999:Multivariate Analysis; D010865:Pilot Projects; D011336:Probability; D011379:Prognosis; D011446:Prospective Studies; D018570:Risk Assessment; D012680:Sensitivity and Specificity
D002245:Carbon Dioxide