Catherine Moore, PharmD
Neurocritical Care Clinical Pharmacy Specialist
Oklahoma University Health
Oklahoma City
Disclosure information not submitted.
G. Morgan Jones, BCPS, PharmD
Clinical Pharmacy Specialist - Neurocritical Care
Methodist LeBonheur Healthcare
Germantown, Tennessee, United States
Disclosure information not submitted.
Lauren Kimmons, BCCCP, BCPS, PharmD
Clinical Pharmacy Specialist
Methodist Healthcare Memphis Hospitals, United States
Disclosure information not submitted.
Title: Impact of Chronic Clonidine Use on Dexmedetomidine Dose Requirements
INTRODUCTION/HYPOTHESIS:
Chronic use of clonidine, a central alpha-2a agonist, may lead to downregulation of receptors. Based on this concept, it is hypothesized that critically ill patients treated with dexmedetomidine, a sedative that exerts its effects through a similar mechanism as clonidine, may require higher doses to reach the targeted effect if the patient was taking clonidine prior to arrival. However, no studies to date have tested this hypothesis. The purpose of this study is to determine the impact of chronic clonidine use on dexmedetomidine dosing requirements.
Methods:
We conducted a retrospective analysis of adult mechanically ventilated patients admitted to the medical or surgical intensive care unit (ICU) from January 2017 to December 2020 who received dexmedetomidine for sedation. Patients were excluded if duration of dexmedetomidine was less than 24 hours, if they had a history of alcohol abuse, and if the titrations were inadequately charted. Patients meeting inclusion criteria were divided into those that were taking clonidine prior to admission and those that were not. The co-primary endpoints were the differences in average and maximum hourly dexmedetomidine rates (microgram per kilogram per hour [mcg/kg/hr]) when comparing those on chronic clonidine versus those not on chronic clonidine.
Results:
A total of 273 patients were screened, and 75 patients met inclusion criteria (clonidine = 25, no clonidine = 50). No statistical differences in baseline characteristics were identified. The majority (76%) of patients included were admitted to the medical ICU. There was no difference in the average hourly (0.6 ± 0.3 vs. 0.5 ± 0.3, p = 0.27) or the median maximum hourly rate (1 [0.6-1.4] vs 1 [0.6-1.4], p=0.86) of demedetomidine. No differences existed between the two groups in duration of ventilation or length of stay in the critical care area. Rates of concomitant continuous sedation were also similar between the two groups.
Conclusions:
Chronic clonidine use was not associated with higher average or maximum hourly rates of dexmedetomidine.