OBJECTIVE: To establish the effect of an audible airleak (around an endotracheal tube) on oxygen consumption (VO2) measurements in pediatric ICU patients. DESIGN: Prospective trial comparing VO2 measurements before and after deflation of the endotracheal tube cuff. SETTING: Pediatric ICU in a large pediatric tertiary care center. PATIENTS: Twenty critically ill infants and children receiving mechanical ventilatory support via cuffed endotracheal tube. INTERVENTIONS: Deflation of endotracheal tube cuff. MEASUREMENTS AND MAIN RESULTS: The presence (group 1, n = 9) or absence (group 2, n = 11) of an audible airleak with the cuff deflated was confirmed by two independent observers. The percent difference in VO2 was calculated for both groups using the following formula: ([VO2 cuff up - VO2 cuff down]/VO2 cuff up) x 100. An audible airleak associated with cuff deflation (group 1) caused a significant (p = .0012) reduction of VO2 by 45.6% (mean difference in VO2 = 45.6%). In contrast, with no audible airleak after cuff deflation (group 2), only minimal changes in VO2 (mean difference in VO2 = -0.4%) were observed. CONCLUSIONS: These data suggest that if no audible airleak is detected, VO2 determined by indirect calorimetry may be reliably measured in infants and children with a noncuffed endotracheal tube.
OBJECTIVE: To establish the effect of an audible airleak (around an endotracheal tube) on oxygen consumption (VO2) measurements in pediatric ICU patients. DESIGN: Prospective trial comparing VO2 measurements before and after deflation of the endotracheal tube cuff. SETTING: Pediatric ICU in a large pediatric tertiary care center. PATIENTS: Twenty critically ill infants and children receiving mechanical ventilatory support via cuffed endotracheal tube. INTERVENTIONS: Deflation of endotracheal tube cuff. MEASUREMENTS AND MAIN RESULTS: The presence (group 1, n = 9) or absence (group 2, n = 11) of an audible airleak with the cuff deflated was confirmed by two independent observers. The percent difference in VO2 was calculated for both groups using the following formula: ([VO2 cuff up - VO2 cuff down]/VO2 cuff up) x 100. An audible airleak associated with cuff deflation (group 1) caused a significant (p = .0012) reduction of VO2 by 45.6% (mean difference in VO2 = 45.6%). In contrast, with no audible airleak after cuff deflation (group 2), only minimal changes in VO2 (mean difference in VO2 = -0.4%) were observed. CONCLUSIONS: These data suggest that if no audible airleak is detected, VO2 determined by indirect calorimetry may be reliably measured in infants and children with a noncuffed endotracheal tube.