Drug usage evaluation of aminoglycoside-induced nephrotoxicity in a community hospital

A DUE was conducted at this institution to determine the incidence of aminoglycoside-induced nephrotoxicity. The charts of all patients (113) who received an aminoglycoside during the first quarter of 1989 were reviewed. Information gathered included patient age, aminoglycoside used, loading and maintenance doses, serum peak and trough concentrations, changes in serum creatinine during aminoglycoside administration, and culture and sensitivity results. Physicians were inconsistent in prescribing loading doses, while all patients dosed by the pharmacy received an initial dose of 1.5 to 1.75 mg/kg of ideal body weight for gentamicin and tobramycin. Ninety percent of maintenance doses were calculated by the pharmacy. All patients had serum peak concentrations between 3 and 10 micrograms/ml, and only three patients had serum trough concentrations greater than 2 micrograms/ml. No patient demonstrated changes in serum creatinine suggestive of clinically apparent nephrotoxicity. This study suggests that with routine pharmacist intervention (via a pharmacist-managed dosing service), aminoglycosides can be prescribed with a low incidence of nephrotoxicity.