Patient selection for serum gentamicin levels

This article describes a set of criteria that can be used to select appropriate patients for serum gentamicin level (SGL) determinations. The set was generated through a critical review of the literature relevant to gentamicin pharmacokinetics and specific patient factors that can influence gentamicin elimination. Gentamicin was chosen because it has been widely used, and a large portion of the body of knowledge concerning aminoglycosides involves gentamicin. Using these criteria, we prospectively evaluated 73 Medical University Hospital patients for appropriateness of sampling. Forty-nine patients (67.2%) were appropriately selected for SGL measurement. This included patients who conformed to at least one criterion and received SGL determination(s), as well as patients who did not conform to any criterion and did not receive a SGL determination. Forty patients (54.8%) conformed to at least one criterion. Although the majority of patients were appropriately selected, only 40% of patients who met at least one criterion received SGL measurement(s). These data suggest the need for greater awareness by the clinician of factors that predispose patients to toxic or subtherapeutic gentamicin therapy.