Reliability of gas sampling from distal end of tracheal tube for PETCO2 monitoring in neonates

Abstract

Objective To evaluate the reliability of gas sampling from the distal end of the tracheal tube for partial pressure of end-tidal CO2(PETCO2)monitoring in neonates. Methods A total of 50 full-term neonates, scheduled for elective abdominal surgery under general anesthesia, aged 1-28 days, weighing 2.55-4.00 kg, of ASA physical status Ⅰ or Ⅱ, were randomly divided into 2 groups(n=25 each)using a random number table: gas samples collected from proximal end of tracheal tube group(group P)and gas samples collected from distal end of tracheal tube group(group D). Epidural catheters of 1 mm in external diameter were used.One end of the catheter was connected to a tube for carbon dioxide sampling, and the other end was inserted into the endotracheal tube and advanced toward the distal hole of the tube.At 15 min of mechanical ventilation, blood samples were collected from the radial artery for record of PETCO2 and for blood gas analysis.Consistency test was performed between PETCO2 and partial pressure of arterial CO2(PaCO2). Results PETCO2 was significantly lower than PaCO2 in the two groups.There was no significant difference in PaCO2between the two groups.PETCO2 was significantly higher in group D than in group P. Kappa was significantly higher in group D than in group P. Conclusion Gas sampling from the distal end of the tracheal tube is more reliable than gas sampling from the proximal end in monitoring PETCO2 in the neonates. Key words: Intubation, intratracheal; Carbon dioxide; Arteries; Monitoring, intraoperative; Infant, newborn