ABSTRACT
To determine the accuracy of end-tidal PCO2(PetCO2) measurement analysed with Ohmeda 5210 capnometer in the pediatric patients whose jung were ventilated with Ohio infant Circle Absorber and Ohio Ventilatior 7200, we compared PetCO2, measurements sampled from the proximal(PetCO2-p) and distal(PetCO2-d) ends of the tracheal tube to arterial PCO2(PaCO2) in 22 healthy pediatric patients between 6.8 to 18.5kg. The results were as follow: 1) Proximal PetCO2 and distal PetCO2 correlated with PaCO2(r=0.76%, SEE=2.79, r=0.70:SEE=3.01, respectively)(p<0.05). 2)Arterial to end-tidal PCO2 difference(delta(a-et)PCO2) was significantyly greater with distal(3.53+/-4.68 mmhg) than proximal(0.35+/-2.72 mmhg) sampling(p<0.05). 3) In subgroup of patients whose proximal to distal concentration of nitrous oxide difference was more than 2%, the delta(a-et)PCO2 using distal sampling(7.90+/-5.15 mmhg) was also significantly greater then it was using proximal sampling(-1.73+/-2.39 mmhg)(p<0.05).. We conclude that distal estimates of PetCO2-P can not provide accepatbale estimate of PaCO2 in healthy pediatric patients who are intubated with pediatric uncuffed tracheal tube.