1262: Lung Compliance Immediately After Tracheal Intubation in the Pediatric Icu

Introduction: The degree of de-recruitment during BMV and laryngoscopy for tracheal intubation has not been quantified. We aimed to describe the degree of lung de-recruitment after successful tracheal intubation, hypothesizing that lung compliance would increase over time after intubation. Methods: Retrospective observational study from a convenience sample of prospectively collected pilot data at an academic pediatric ICU. A quantitative respiratory function monitor recorded pressure and volume metrics immediately after tracheal intubation in children. Post-intubation compliance was calculated using expiratory tidal volume (VTe)/driving pressure (dP: peak inspiratory pressure minus positive end expiratory pressure). Compliance was averaged over 3 ventilation breaths at 6 time points (immediately after intubation [C1], after 10, 20, 30, 40, and 50 [C50] breaths). Post-intubation lung de-recruitment was calculated by (C50 – C1)/C50. The association between post-intubation lung de-recruitment and age and respiratory pathology (i.e., respiratory tract disease or anatomy affecting pulmonary resistance or compliance) was evaluated with Wilcoxon rank-sum tests. Results: Among 79 patients with post-intubation ventilation data, 24% were infants (< 1 year), 49% were 1-7 years, and 27% were 38 years; 35% had respiratory disease. The median apneic time for laryngoscopy was 53 [IQR 43, 81] seconds. The median 3-ventilation averaged lung compliance immediately after intubation was 2.1 [1.3, 4.3] mL/cmH2O, and was 3.4 [1.6, 6.0], 4.1 [2.0, 6.6], 3.9 [2.6, 7.1], 4.0 [2.5, 7.0], and 4.9 [3.0, 7.6] mL/cmH2O at 10, 20, 30, 40, and 50 breaths. Median post-intubation de-recruitment was 49% [25%, 74%]. Infant vs non-infant age category (28% [0.5%, 60%] vs 54% [28%, 79%], p=0.02) was associated with lung de-recruitment, whereas respiratory pathology was not (p=0.67). Conclusions: Substantial lung de-recruitment was common after tracheal intubation in the PICU. Post-intubation lung compliance gradually increases with ventilation after intubation. Further exploration is needed to understand why infants had less lung de-recruitment.