Andrew Robinson, PharmD, BCCCP,
Community Health South
Indianapolis, Indiana
Disclosure information not submitted.
Whitney Chaney, PharmD, BCPS, BCCCP
Surgical/Trauma Intensive Care Unit Clinical Pharmacist
Loyola University Medical Center, United States
Disclosure information not submitted.
Title: Weight based continuous infusion fentanyl is associated with higher rates of fentanyl exposure
INTRODUCTION/HYPOTHESIS: According to the 2018 SCCM Pain, Agitation, Delirium, Immobility, and Sleep (PADIS) guidelines, fentanyl is a first line agent for pain control in the ICU. In pharmacokinetic studies in critically ill patients on fentanyl continuous infusions (CI), fentanyl serum concentrations were elevated in patients with body mass index (BMI) < 20 and accumulation of fentanyl was found in patients with BMI >30, indicating that a weight based dosing (WBD) approach may not be optimal. The goal of this study is to determine if fentanyl CI dosed in mcg/hour as compared to mcg/kg/hr is associated with any differences in total fentanyl exposure.
Methods: This was a retrospective, single-centered, cohort study of mechanically ventilated (MV) adult patients who received CI fentanyl from January 2015- March 2017. The primary endpoint was the cumulative CI fentanyl dose. Secondary endpoints included duration of MV, time Richmond Agitation and Sedation Scale (RASS) scores were in goal range, ICU and hospital lengths of stay, total opioid exposure, failed extubations, and adverse events.
Results: A total of 63 patients in the WBD group and 65 patients in the non-WBD group were analyzed. Baseline characteristics were similar between groups in regards to age and BMI. There were significantly lower total CI fentanyl doses in the non-WBD fentanyl group, median (IQR) 4450 mcg (2190-11016.25) vs. 10132.5 mcg (4310-28682.5), p< 0.001. Secondary outcomes showed significantly lower total opioid use during hospital stay expressed in morphine milligram equivalents (MME) in the non-WBD group, median (IQR) 696 MME (341.73-1605.38) vs. 1465.12 MME (647-3512.25), p=0.003. There was no observed difference in MV free days at 28 days in the non-WBD fentanyl group compared to the WBD group, mean (SD) 20.6 (7.39) days vs. 19.7 (7.21) days, p=0.46. Time in goal RASS was similar with 76.9% in the WBD group and 75.5% in the non-WBD group. Rates of ileus were similar between groups with 20.6% in the WBD group and 20% in the non-WBD group.
Conclusions: This study demonstrated a significant reduction in total fentanyl exposure and overall opioid use with a non-WBD fentanyl infusion dosing strategy in comparison to WBD fentanyl dosing. Duration of MV and time in RASS goal remained similar for both dosing strategies.