The pharmacy cost of delivering postoperative analgesia to patients undergoing joint replacement surgery☆

Few data exist on the distribution of pharmaceutical costs for inpatient surgical procedures across different drug categories (eg, analgesia, anti-infectives). The goals of this study were to categorize pharmaceuticals administered to patients after joint replacement surgery and then to take the hospital[apos ]s perspective and quantify the pharmacy cost of delivering postoperative analgesia to these patients. Two hundred ninety-eight patients undergoing unilateral hip replacement (n [equals] 145), unilateral knee replacement (n [equals] 121), or bilateral knee replacement (n [equals] 32) were studied retrospectively. For each patient, we determined what hospital resources (eg, supplies) were utilized by each patient in each of 12 different hospital departments. This was done to determine what fraction of overall hospital costs was incurred as a result of pharmacy. Then, we classified the hundreds of items (from acetaminophen to warfarin) included as pharmacy costs into 1 of the following categories: postoperative epidural analgesia, opioids, nonopioids, respiratory, gastrointestinal, naloxone, anti-infective, anticoagulant/antiplatelets, miscellaneous, cardiovascular, pharmacist clinical intervention, intravenous fluids, and benzodiazepines. The pharmacy costs for epidural analgesia, opioids, and nonopioids were summed to compute the fraction of pharmacy costs attributed to postoperative analgesia. The results showed that 3.3% (95% confidence interval [lsqb ]CI[rsqb ], 2.7% to 3.6%) of total hospitalization costs were pharmacy costs, which averaged $560 (95% CI, $500 to $620) for hip replacement, $595 (95% CI, $551 to $639) for knee replacement, and $922 (95% CI, $588 to $1256) for bilateral knee replacement surgery. An average of 9.9% (95% CI, 7.37% to 12.43%) of total pharmacy costs for the 3 surgery types were for postoperative epidural analgesia, whereas opioids averaged 19.9% (95% CI, 18.67% to 21.13%), and nonopioids averaged 0.8% (95% CI 0.65% to 0.95%) of pharmacy costs. Thus, analgesics accounted for approximately 31% of pharmacy costs. The pharmacy cost of delivering postoperative analgesia to patients undergoing joint replacement surgery represents 1% of the total costs of surgery. Almost two thirds of the analgesic costs were for opioids. [copy ] 2003 by the American Pain Society