Drug-related problems in patients undergoing elective total joint arthroplasty of the hip or knee.

BACKGROUND Few studies have evaluated drug-related problems in patients undergoing elective total hip or knee arthroplasty. OBJECTIVE To quantify, for patients undergoing elective total joint arthroplasty, drug-related problems arising from medication orders written before or immediately after the surgery. The primary outcome was the proportion of patients with at least one drug-related problem. The secondary outcomes were the total number and descriptions of these problems, according to the patient's age and the category, type, and severity of the drug-related problem. METHODS From among patients who underwent elective total joint arthroplasty in a large Canadian regional health authority in 2005, 150 were randomly selected for this chart audit. Patients were included if they had been taking more than one medication before surgery. The charts were examined for drug-related problems, which were categorized according to whether the problem involved a prescription for a home medication, an order for a postoperative medication, or a potential indication for drug therapy. The problems were further described by type and potential severity. RESULTS Of the 146 patients whose charts were available, 116 (79.5%) had at least one drug-related problem, with a mean of 1.88 drug-related problems per patient. Of the 146 patients, 88 (60.3%) had at least one drug-related problem involving a home medication, 34 (23.3%) had problems related to postoperative orders, and 37 (25.3%) had problems related to a potential indication. The mean number of drug-related problems per patient was 2.03 for those 65 years of age or older and 1.56 for those younger than 65 years (p = 0.09); however, more of the older patients experienced at least one drug-related problem related to home medications (67% [67/100] versus 46% [21/46], p = 0.02). The most common types of problems were medication omissions, illegible drug orders, inappropriate dose or frequency, and drug-allergy interactions. Of the 275 drug-related problems identified, 147 (53.5%) were deemed potentially harmful, 78 (28.4%) required monitoring, and 50 (18.2%) were considered not harmful. CONCLUSIONS In this study, patients who underwent total joint arthroplasty experienced many drug-related problems. Pharmacists may have opportunities to optimize patient care by identifying, resolving, and preventing drug-related problems in this patient population.