We aimed to investigate the effect of a basal opioid infusion in fentanyl-based intravenous patient-controlled analgesia (IV-PCA) on postoperative opioid consumption, pain intensity, and occurrence of opioid-related side effects. Patients and Methods: We retrospectively reviewed 2097 consecutive patients who received IV-PCA after elective general, thoracic, urologic, and plastic surgery under general anesthesia between June 2019 and October 2019. The patients were divided into two groups: IV-PCA with basal infusion (basal group) and IV-PCA without basal infusion (no basal group). We performed a propensity score matching (PSM) analysis to adjust for baseline differences between both groups. We compared the fentanyl PCA consumption (mcg), pain intensity, rescue analgesic administration, and occurrence of opioid-related side effects (nausea, vomiting, somnolence or dizziness, and overall side effects) during the first 48 hours postoperatively between the two groups before and after PSM. Results: We analyzed 1317 eligible patients. Of these, 757 (57.5%) patients received IV-PCA without basal infusion. The PSM of the total cohort yielded 539 pairs of cases. After PSM, the fentanyl PCA consumption was significantly lower in the no basal group at 48 hours postoperatively as compared to the basal group (at 24 hours, the median difference: −80 mcg, P<0.001, 95% CI=−112-−45 mcg; at 48 hours, the median difference: −286 mcg, P<0.001, 95% CI=−380-−190 mcg), without significantly increasing pain intensity and administration of rescue analgesia. The occurrence of overall opioid-related side effects was also significantly lower in the no basal group (at 24 hours: 31.0% vs 23.0%, OR=0.67, P=0.003, 95% CI=0.51-0.87; at 48 hours: 18.9% vs 11.0%, OR=0.48, P<0.001, 95% CI=0.31-0.75). Conclusion: Basal infusion of fentanyl-based IV-PCA was significantly associated with an increase in fentanyl consumption and the occurrence of opioid-related side effects in postsurgical patients.

Purpose: Although the use of opioids is increasing in South Korea, there have been no studies on the serious complications caused by the opioids. The aim of this study was to investigate the rare but serious complications through medicolegal analysis. Materials and Methods: From January 1994 to December 2019, we retrospectively reviewed the closed cases of lawsuits involving the complications of opioids using the database of judgments of the Supreme Court of Korea. General characteristics, opioidinduced complications, and judicial characteristics were analyzed. Results: Of the 46 cases, 31 cases of complications were finally included in the analysis. There were 28 (90.3%) cases of opioid administration for acute pain and 3 (9.7%) cases for chronic pain. The most commonly prescribed opioid was pethidine (n = 13, 41.9%), and the most common complication was respiratory depression (n = 17, 54.8%). All except two cases were associated with permanent injuries, including 18 (58%) deaths. Twelve (38.7%) cases were ruled in favor of the plaintiff in the claims for damages, with a median payment of United States dollar (USD) 126,346 (IQR: USD 77,275-379,219). Of these cases, the most frequently admitted complaint by the court was the neglect of observation (n = 10, 32.3%), followed by the inappropriate drug choice (n = 4, 12.9%). Eleven (36.7%) cases were plaintiffs' claims for violating explanation obligations, of which 2 (6.7%) were recognized in the court. Conclusion: Our results suggest that physicians must be aware of the serious complications related to opioids and health policies to prevent such complications and malpractice should be adopted.