Opioid Withdrawal in Critically Ill Adults A Retrospective Study to Identify at Risk Patients

Pharmacy residents have the opportunity to complete a research project during their residency training, which provides them with skills on how to conduct and manage a research project. Projects often represent an area of interest and need that has been recognized by the host institution’s pharmacy department. Projects are presented as a poster at an annual CSHP Ontario Branch Residency Research Night, and many eventually go on to be published in a peer-reviewed journal.Background: The incidence of opioid withdrawal and associated symptoms in critically ill adults has not been adequately studied. The lack of dedicated scales for the detection of iatrogenic opioid withdrawal syndrome (IOWS) in critically ill adults represents a gap in the literature. Objectives: To 1) determine the feasibility of identifying patients at risk of IOWS for a future study evaluating IOWS in critically ill adults 2) determine the frequency of documentation of potential signs and symptoms of IOWS; 3) determine patterns of opioid doses used in critically ill adults. Methods: A retrospective chart review of critically ill adults (aged ≥ 18 years) who received regularly administered opioids for at least 72 hours in the ICU. Patient charts were reviewed for documentation of signs and symptoms of opioid withdrawal using a checklist of 17 symptoms developed from a review of the literature. Feasibility was defined as the ability to include 20 subjects in 1 year. Results: One thousand, one hundred and eighteen subjects were screened between December 2016 and December 2017. Twenty-eight subjects were included. The median age was 65 years. Male sex comprised 61% of subjects. The most common reason for exclusion was not receiving scheduled opioids in ICU for ≥ 72 hours (91.7%.) The most commonly documented symptom was a ≥ 15% variance in respiratory rate (92.5% frequency of documentation). Documentation of the absence of symptoms was rare (< 1%). The symptoms least commonly documented were piloerection and lacrimation (0% frequency of documentation, respectively). Median daily opioid dose changes were + 13%, - 5%, -19% and -22% on days 2, 3, 4 and 5, respectively. The most frequently used opioids were IV Fentanyl, IV Hydromorphone, and Oral Hydromorphone, representing 70.1%, 42.5%, and 21.6% of patient days, respectively. Conclusions: In identifying 28 patients at risk of IOWS, our findings demonstrate the feasibility identifying patients at risk of IOWS for a future study evaluating IOWS in critically ill adults. Data on the frequency of documentation of 17 symptoms suggest a wide range of documentation frequency and may inform the choice of symptoms assessed in future studies of IOWS. Our data identified 20% dose reductions beginning on day 4, which informs a standardized dose reduction to be tested in an interventional study