Erika Zarfoss, PharmD, BCPS, BCCCP,
Clinical Pharmacy Specialist, Critical Care and Emergency Medicine
West Virginia University Medicine J.W. Ruby Memorial Hospital
Morgantown, West Virginia
Disclosure information not submitted.
Jeffery Garavaglia, PharmD, BCCCP
Clinical Pharmacy Specialist, Neurocritical Care
West Virginia University Medicine, United States
Disclosure information not submitted.
Jeremiah Hayanga, MD, MPH, MHL
Professor, Department of Cardiovascular & Thoracic Surgery; Director, WVU ECMO Program
West Virginia University Medicine, United States
Disclosure information not submitted.
Galen Kabulski, PharmD, BCPS, BCCP
Clinical Pharmacy Specialist, Cardiothoracic Critical Care
West Virginia University Medicine, United States
Disclosure information not submitted.
Title: Comparison of Standard Versus High Dose Dexmedetomidine in Extracorporeal Membrane Oxygenation
Introduction:
Dexmedetomidine (DEX) is an α-2 adrenergic agonist which provides light sedation with recommended doses of 0.2-1.5mcg/kg/hr. Extracorporeal membrane oxygenation (ECMO) circuits have been shown to sequester DEX through in-vitro studies, which may alter pharmacokinetics and clinically impact dosing. In-vivo data assessing DEX in ECMO patients is currently lacking. The purpose of this study was to compare safety and efficacy of DEX at standard (≤1.5mcg/kg/hr) vs high doses ( >1.5mcg/kg/hr) in ECMO.
Methods:
A single-center retrospective analysis of ECMO patients from January 2014 to June 2020 was performed. Included patients were ≥ 18 years of age and received continuous infusion DEX for at least 24 hours while on ECMO. Patients were compared as receiving either standard (≤1.5mcg/kg/hr) or high ( >1.5mcg/kg/hr) dose DEX, defined by the highest rate of DEX given at any time during therapy. Safety outcomes included new onset bradycardia (HR < 60 BPM or need for pacing), or hypotension (MAP < 60mmHg or addition of vasoactive medications). Efficacy was compared by the addition of concomitant sedative and analgesic agents.
Results:
Of the 105 patients evaluated, 20% received DEX at rates higher than 1.5 mcg/kg/hr. Comparing standard and high dosing, no significant differences were seen in primary safety outcomes including bradycardia (49 vs 38%, p=0.46), hypotension (79 vs 71%, p=0.56), or addition of vasopressors (75 vs 71%, p=0.78). No significant difference was seen in the addition of any analgesic (77% vs 86%, p=0.55) or the total fentanyl equivalents per day. Similar rates of concomitant sedative agents including propofol (43% vs 30%) and antipsychotic agents (62% vs 39%) were observed. Higher rates of continuous infusion ketamine (20% vs 48%, p=0.02) and benzodiazepines (4% vs 19%, p=0.03) were seen in the high dose DEX group.
Conclusions:
Rates of DEX higher than 1.5 mcg/kg/hr are commonly used in patients on ECMO, with similar rates of adverse effects and need for additional sedation and analgesia. While high dose DEX may be as safe as standard dose, no additional efficacy was found. To our knowledge, this is the first study evaluating the in-vivo use of DEX in patients on ECMO support.