696: FACTORS ASSOCIATED WITH SUCCESSFUL ERT IN CHILDREN WITH CONGENITAL HEART DISEASE

Abstract

Introduction: In children with congenital heart disease, extubation readiness testing (ERT) is performed to evaluate mechanical ventilation liberation potential. There are minimal data suggesting what mechanical ventilation parameters are associated with successful ERT. We hypothesized that ERT success would be associated with mechanical ventilator parameters. Methods: Data on daily ERT assessments were recorded as part of an IRB approved QI project. As part of our RT-driven ventilator protocol, patients are assessed daily for ERT eligibility and tested daily, if eligible. Mechanical ventilation parameters were categorized a priori to evaluate differences in ventilator settings. The primary outcome was ERT success. ERT outcome was compared using the chi-square and Mann-Whitney test. Categorical data are reported as n (%), continuous data as median (interquartile range). Logistic regression was performed to evaluate factors associated with successful ERT and reported as odds ratio (OR). Results: We evaluated 780 ERTs from 320 subjects [median age 2.5 (0.6-6.5) months, 4.2 (3.3-6.9) kg]. 528 (68%) of ERTs were passed, 306 (58%) subjects were extubated after successful ERT and 30 (9.4%) were reintubated. There were significantly differences in ERT pass rate for ventilator mode (65% SIMV, 81% pressure support, 53% assist/control), PIP [17 (15-19) vs 19 (17-22) cmH2O], Δ pressure [12 (10-14) vs 14 (12-15) cmH2O], PEEP [5 (5-6) vs 6 (5-6) cmH2O], MAP [9 (8-10) vs 10 (9-11) cmH2O], and VD/VT [0.35 (0.28-0.42) vs 0.40 (0.33-0.46)] (all p< 0.001], but not for FiO2 [0.30 (0.21-0.40) vs 0.30 (0.23-0.35), p=0.14]. ERT success decreased with increases in PIP (87% ≤ 15 cmH2O, 66% 16-20 cmH2O, 50% 21-25 cmH2O, 27% 26-29 cmH2O), Δ pressure (85% ≤ 10 cmH2O, 63% 11-15 cmH2O, 51% 16-19 cmH2O, 22% ≥ 20 cmH2O), PEEP (73% ≤ 5 cmH2O, 63% 6 cmH2O, 42% 7 cmH2O), MAP (81% ≤ 8 cmH2O, 67% 9-10 cmH2O, 40% > 10 cmH2O, and VD/VT (75% < 0.30, 68% 0.31-0.40, 62% 0.41-0.50, 46% >0.50). Logistic regression revealed neonates, Δ pressure ≥11 cmH2O, and MAP > 10 cmH2O were associated with a decreased odds of ERT success while children aged 1-5 and an FiO2 0.31-0.40 had increased odds of ERT success. Conclusions: ERT pass rates decreased as ventilator support increased; however, some subjects passed ERT despite high ventilator support.