A retrospective cohort Study Exploring Existing Sedation, Analgesia and Withdrawal management in a Paediatric Intensive Care Unit (PICU): The SEESAW study

Abstract

PURPOSE Paediatric Intensive Care Unit (PICU) patients are at risk of developing withdrawal when high doses of opioid analgesics and sedatives are stopped or tapered too rapidly. The primary aim of the study was to explore the factors associated with the increased incidence of withdrawal in order to better understand the extent of the problem. The secondary aim was to analyse if the presence of withdrawal syndrome was associated with clinical complications or delayed recovery. METHODS The retrospective chart audit examined the medical records of 120 mechanically ventilated infants and children that were admitted to the PICU within a tertiary children’s hospital from 2015 to 2017. The patients were selected if exposed to at least 24 hours of continuous opioid or sedative infusion. The presence of withdrawal syndrome was assessed retrospectively using the Sophia Observation of withdrawal Symptoms (SOS) scale. The retrospective cohort study provided a means to report on the natural course of untreated and under-treated withdrawal. A multivariate regression model analysed variables associated with withdrawal. RESULTS Overall, the incidence of withdrawal in the study cohort was 61% (73/120). This included 45 patients that had been diagnosed with withdrawal by the clinical team and 28 that were undiagnosed. Patients that received fentanyl were more likely to develop withdrawal compared to patients that received morphine (RR 1.5, 95% CI 0.96-2.20). However, the mean infusion rate was significantly (3.4 times) higher for fentanyl, accounting for the difference. The mean opioid infusion rate and infusion duration were both associated with withdrawal to varying degrees. High mean infusion rates of 3 mcg/kg/hr fentanyl and 80 mcg/kg/hr morphine were 80% predictive of precipitating withdrawal. Dose tapering characteristics were analysed and demonstrated that the patients that developed withdrawal were typically tapered from a dose of 3 mcg/kg/hr fentanyl over 0-24 hours. Patients with withdrawal symptoms had significantly higher rates (24/73 vs 4/47) of severe clinical deterioration within 72 hours of opioid dose tapering (OR 5.8, 95% CI 1.8-18.5, p = 0.003). Severe clinical deterioration included seizures, aspiration events, life-threatening arrhythmias, hypoglycaemia, and respiratory failure that required intubation or mechanical ventilation. Comparing outcomes, patients with withdrawal had prolonged PICU (8.0 vs 4.7 days, p = 0.001) and hospital (23 vs 14 days, p = 0.003) length of stay. CONCLUSION The SEESAW study demonstrated that significantly higher mean infusion rates of fentanyl were administered to patients in PICU, compared to morphine. The incidence of withdrawal was predominantly fentanyl dose-driven. Using the retrospective SOS scale results, the presence of withdrawal was associated with increased clinical complications and delayed recovery.