Prescriber adherence to pharmacokinetic monitoring service recommendations for aminoglycoside dosing and the risk of acute kidney injury

The importance of adherence to aminoglycoside dosing recommendations by a pharmacokinetic monitoring service for preventing acute kidney injury (AKI) is unknown. We aimed to examine the association between AKI and discordance in aminoglycoside dosing between physician orders and recommendations by a pharmacokinetic monitoring service. We utilized 2000 - 2003 data from a large quaternary care academic medical center, including: hand-written pharmacokinetic monitoring service recommendations; computerized physician order entry inpatient medication orders; and electronic inpatient laboratory orders and results. We conducted a case-control study, nested within users of intravenous aminoglycosides. Outcomes of interest were cases of AKI, as determined by changes in serum creatinine. Exposures of interest were discordances between pharmacokinetic monitoring service recommendations and physician orders in the past 2 days with regard to total daily aminoglycoside dose. Most patients received once-daily or less frequent aminoglycoside dosing. In 1,414 evaluable aminoglycoside courses, 220 patients developed AKI, for a cumulative incidence of 15.6%. We identified 690 controls, matched these to 220 cases, and found adjusted odds ratios of 0.72 (95% CI: 0.37 - 1.39) for overdose discordance and of 0.83 (0.51 - 1.34) for underdose discordance, suggesting that discordance in dosing is not associated with AKI. Non-adherence to dosing recommendations for aminoglycosides was not associated with risk of AKI in a setting primarily of once-daily aminoglycoside administration.