(1015) Sedation and Withdrawal in Infants Who Required Mechanical Ventilation for Bronchiolitis

Introduction: Children who require mechanical ventilation for acute respiratory failure associated with bronchiolitis are often sedated with opioids, alpha 2-agonists, and benzodiazepines. This study adds insight into withdrawal risk factors and prevention techniques by assessing withdrawal in a single disease process.

Methods: Patients admitted between 1/1/12 and 1/1/22 with bronchiolitis (ICD code J21 or 466.1, under two years) who required mechanical ventilation and were extubated successfully were included in the analysis (N = 430). The opioid infusion wean was divided into 8-hour epochs for each patient, starting with the first 10% wean sustained for 24 hours. Cumulative opioid, benzodiazepine, and alpha 2-agonist exposure were quantified at the start of each epoch; change in exposure between epochs was quantified as well. Patient-specific variables included the presence of two or more complex chronic conditions (CCCV2), heart disease, prematurity, and trisomy 21. Withdrawal was defined as a withdrawal assessment tool (WAT-1) score greater than or equal to 3. Withdrawal events and withdrawal-range WAT-1 score values were simultaneously modeled using a zero-inflated model with autoregressive and random effects per patient.

Results: Patients had a median age of 5.5 months and were 58% male. Patients who developed withdrawal had a median of 8.3 days of opioid exposure (N = 367); patients who did not develop withdrawal had a median of 5.2 days of opioid exposure (N = 63). Both groups received a median of 0.2mg/kg/hour of morphine equivalents. Increased odds of withdrawal were associated with cumulative opioid exposure (OR 1.03 95% CI 1.02-1.03) and use of morphine as the primary opioid (1.98, 1.45-2.71). Decreased odds of withdrawal were associated with methadone exposure (0.67, 0.63-0.72) and trisomy 21 (0.35, 0.14-0.89). For withdrawal-range WAT-1 scores, cumulative opioid exposure was associated with higher WAT-1 scores and cumulative methadone, midazolam, and dexmedetomidine exposure were associated with lower WAT-1 scores.

Conclusions: Cumulative opioid exposure and use of morphine as a primary opioid are associated with an increase in both withdrawal risk and severity in infants with bronchiolitis who required mechanical ventilation.