Objective: Opioids are commonly used in pediatric intensive care units for analgesia, sedation and to minimize the stress response during mechanical ventilation (MV) in critical illness. Prolonged and increasing opioid dose exposure for patients can result in tolerance complicating the therapeutic effect and increasing the risk of dangerous iatrogenic withdrawal syndrome. Optimizing management with the least effective dosing is beneficial. Clinicians have used a strategy of rotating agents within the class of opioids to lessen dose exposure and mediate tolerance thus improving outcomes. This study seeks to identify the dose exposure for those patients using that strategy.
Methods: A retrospective review of a quaternary pediatric ICU from June 2018 to July 2020. All patients admitted with the primary diagnosis of acute respiratory failure requiring MV for ≥ 5 days and receiving opioids. Those patients with tracheostomy or extracorporeal circulatory or renal support were excluded. Medical complexity was defined as pre-hospital co-morbidities that may complicate ICU stay. Logistic analysis was performed.
Results: A total of 218 patients had 243 MV events within 227 hospitalizations in the study period. The majority were previously healthy (97%). Assessment of sedation management revealed that 17% (n=37) had opioid rotation as part of the sedation strategy. Median age and weight were 2.7 years (IQR 2, 4.9) and 8.3kg (IQR 4.8, 13.3) respectively with MV median of 8 days (IQR 6,11) and PRISM scores were not different between groups (p =0.05). Patients with opioid rotation as compared to those that did not were older (p = 0.001), heavier (p < 0.001), had longer MV (p < 0.001) and were more medically complex (p < 0.001). Rotation patients had increased total opioid dose vs. non-rotators, 211 vs. 70 morphine milligram equivalents (MME)/kg, (p < 0.001). After adjusting for medical complexity, race, MV days, weight, age, and sex, the rotation group remained significant with a higher total opioid dose (p = 0.023), 136% higher than those without.
Conclusion: Although thought to alleviate high opioid dose exposure, sedation strategies using opioid rotation for pediatric patients with respiratory failure on MV increase the total opioid dose exposure by greater than 100% as compared to those without opioid rotation.
