Postoperative Respiratory Events in Surgical Patients Exposed to Opioid Analgesic Shortages Compared to Fully Matched Patients Non-exposed to Shortages.

Abstract

Shortages of opioid analgesics critically disrupt clinical practice and are detrimental to patient safety. There is a dearth of studies assessing the safety implications of drug shortages. We aimed to assess perioperative opioid analgesic use and related postoperative hypoxemia (oxygen saturation less than 90%) in surgical patients exposed to prescription opioid shortages compared to propensity score-matched patients non-exposed to opioid shortages. We conducted a retrospective study including adult patients who underwent elective surgery at The University of California San Francisco in the period August 2018-December 2019. We conducted a Gamma log-link generalized linear model to assess the effect of shortages on perioperative use of opioids and a weighted logistic regression to assess the likelihood of experiencing postoperative hypoxemia. There were 1119 patients exposed to opioid shortages and 2787 matched non-exposed patients. After full matching, patients exposed to shortages used a greater mean of morphine milligram equivalents/day (146.94; 95% confidence interval 123.96-174.16) than non-exposed patients (117.92; 95% confidence interval 100.48-138.38; p=0.0001). The estimated effect was a 1.25 (95% confidence interval 1.12-1.40; p=0.0001) times greater use of opioids in patients exposed to opioid shortages than non-exposed patients. After full matching, a greater proportion of patients exposed to shortages (19.06%) experienced hypoxemia compared with non-exposed patients (16.91%). In addition, a greater proportion of patients exposed to opioid shortages (1.20%) experienced hypoxemia reversed by intravenous naloxone administration compared with non-exposed patients (0.44%). Given the shortage prevalence, reliance on opioid medications, and related risk of respiratory depression, harm prevention measures remain critical to prevent postoperative complications that may compromise patients' safety.