Objective To determine the immediate effect of open endotracheal suction (ETS) to remove obstructive secretions on spirometry (TVexp, Pw, Compliance, PEEP, PIP, RR), VO2 – VCO2 measurements and calculated respiratory quotient (RQ) and resting energy expenditure (REE) in mechanically ventilated (MV) critically ill children by means of a prospective observational clinical study.
Methods A total of 650 pulmonary 1-min gas exchange measurements were recorded for 50 consecutive minutes before (B) and 50 after (A) the standardised suctioning procedure in 13 children without lung pathology, MV for sepsis or head injury. The patients were well sedated but not paralysed and were able to breathe spontaneously.
Results There was no difference between the A and B set of measurements in VO2 (121±15 ml/min vs. 119±15 ml/min) or VCO2 (104.8±17 ml/min vs. 105.3±18 ml/min) or calculated RQ (0.87±0.008 vs. 0.88±0.009) or REE (847±106 kcal vs. 838±108 kcal). Ratio differences of A and B means after Bland & Altman were kept within the clinically acceptable limits of 10% (VO2 −1.8%, VCO2 0.5%, RQ 1.6%, REE −1.2%). Ratio differences between the 25-first and 25-second sets of measurements did not differ in either group. Similarly, FiO2, SaO2, Spirometric (TVexp, Pw, compliance, PEEP, PIP, RR) and hemodynamic measurements did not differ between groups.
Conclusions Accuracy of VO2 and VCO2 measured by E-COVX is not influenced by endotracheal suction in MV children without lung pathology.