Impact of Dexmedetomidine Infusion on Opioid and Benzodiazepine Doses in Ventilated Pediatric Patients in the Cardiac Intensive Care Unit.

INTRODUCTION: Dexmedetomidine (DEX) is frequently used as an adjunct agent for prolonged sedation in the intensive care unit (ICU), though its effect on concomitant opioids or benzodiazepines infusions is unclear. We explored the impact of DEX on concomitant analgosedation in a cohort of ventilated pediatric patients in a cardiac ICU, with stratification of patients according to duration of ventilation (< 5 versus ≥ 5 days) following DEX initiation. METHODS: We conducted a retrospective analysis on ventilated patients receiving a DEX infusion ≥ 24 h and at least one other sedative/analgesic infusion (January 2011-June 2021). We evaluated trends of daily doses of opioids and benzodiazepines from 24 h before to 72 h following DEX initiation, stratifying patients based on ventilation duration after DEX initiation (< 5 versus ≥ 5 days). RESULTS: After excluding 1146 patients receiving DEX only, 1073 patients were included [median age 234 days (interquartile range 90, 879)]. DEX was associated with an opioid infusion in 99% of patients and a benzodiazepine infusion in 62%. Among patients ventilated for < 5 days (N = 761), opioids increased in the first 24 h following DEX initiation [+ 1.12 mg/kg/day (95% CI 0.96, 1.23), P < 0.001], then decreased [- 0.90 mg/kg/day (95% CI - 0.89, - 0.71), P < 0.001]; benzodiazepines slowly decreased [- 0.20 mg/kg/day (95% CI - 0.21, - 0.19), P < 0.001]. Among patients ventilated for ≥ 5 days (N = 312), opioid administration doubled [+ 2.09 mg/kg/day (95% CI 1.82, 2.36), P < 0.001] in the first 24 h, then diminished minimally [- 0.18 mg/kg/day (95% CI - 0.32, - 0.04), P = 0.015] without returning to baseline; benzodiazepine administration decreased minimally [- 0.03 mg/kg/day (95% CI - 0.05, - 0.01), P = 0.010]. Similar trends were confirmed when adjusting for age, gender, surgical complexity, recent major invasive procedures, duration of mechanical ventilation before DEX initiation, extubation within 72 h following DEX initiation, mean hourly DEX dose, and use of neuromuscular blocking infusion. CONCLUSION: While in patients ventilated < 5 days opioids initially increased and then quickly decreased in the 72 h following DEX initiation, among patients ventilated ≥ 5 days opioids doubled, then decreased only minimally; benzodiazepines decreased minimally in both groups, although more slowly in the long-ventilation cohort. These findings may inform decision-making on timing of DEX initiation in ventilated patients already being treated with opioid or benzodiazepine infusions.