Evaluation of a computer-assisted antibiotic-dose monitor

OBJECTIVE: To examine the effect of a computer-assisted antibiotic-dose mon itor used to reduce the number of days that patients receive excessive dosa ges of antibiotics and the number of adverse drug events (ADEs) secondary t o antibiotics. DESIGN: Descriptive epidemiologic study of a two-year preintervention perio d and one-year intervention period. SETTING: The LDS Hospital, a tertiary care center iu Salt Lake City, UT. PATIENTS: All patients aged greater than or equal to 18 years, admitted to LDS Hospital from April 1, 1993, to March 31, 1996, who received at least o ne of five targeted antibiotics (vancomycin, gentamicin, imipenem, cefazoli n, cefuroxime), who had a serum creatinine or a urine creatinine clearance test result before antibiotic therapy, and who were never admitted or trans ferred to the shock/trauma/respiratory intensive care unit. METHODS: Each morning during the 12-month intervention period, the antibiot ic-dose monitor checked the renal function of all patients who were receivi ng any of the five antibiotics. Pharmacists received a computer listing of patients who may have been receiving excessive dosages. The antibiotic-dose monitor suggested an alternate dosage and a pharmacist contacted the patie nt's physician if the suggested change in the dosage was appropriate. RESULTS: During the intervention period, 4483 patients received at least on e of the five study antibiotics and 1974 (44%) were identifed as receiving an excessive dosage, compared with 4494 (50%) of 8901 patients during the p reintervention period (p < 0.001). The patients receiving excessive dosages received an excessive dosage for an average of 2.9 days during the interve ntion period, compared with 4.7 days (p < 0.001) during the preintervention period. in addition, these same patients during the intervention period re ceived fewer doses of antibiotics (10.9 vs. 13.4; p < 0.001), fewer grams o f antibiotics (10.4 vs. 12.0; p < 0.02), at less cost ($98 vs. $128; p < 0. 004) than the patients during the preintervention period. Moreover, there w ere 14 ADEs (0.3%) secondary to the five study antibiotics during the inter vention period, compared with 82 (0.9%; p < 0.001) for the two-year preinte rvention period. The study also found that significantly more patients iden tified as receiving excessive dosages had experienced decreases in renal fu nction, compared with patients who were not identified as receiving excessi ve dosages (25% vs. 12% during preintervention period and 23% vs. 16% durin g intervention period; p < 0.001). CONCLUSIONS: Many patients experience decreases in renal function after ant ibiotics are ordered. The use of the computer-assisted antibiotic-dose moni tor appears to be a promising method to help reduce the excessive use and c ost of antibiotic therapy and reduce the number of ADEs secondary to antibi otics.