Impact of the PK/PD Approach in Therapeutic Drug Monitoring of Gentamicin

Abstract

Gentamicin, a commonly used hospital aminoglycoside, exhibits a narrow therapeutic index, necessitating careful administration to prevent serious adverse effects. Our study aimed to assess the impact of Therapeutic drug Monitoring (TDM) by integrating Minimum Inhibitory Concentration (MIC) to customize dosage based on bacterial sensitivity. This was prospective study, conducted on a sample of 35 adult patients hospitalized in three university hospital centers in Eastern Algeria. Included patients underwent Therapeutic Drug Monitoring (TDM) of gentamicin based on the determination of Maximum concentration (Cmax), considering the determination of the MIC and achieving a Cmax/CMI ratio ≥ 8 to 10. Pharmaceutical interventions were suggested to clinicians to improve patient care. The mean age of our patients was 51.66 ± 16.72 years. All patients had Cmax values below the therapeutic range. Pathogenic microorganisms were identified in 64% of cases, and only two patients achieved the Cmax/CMI target of 8 to 10 prior to our interventions. In 41% of cases, clinicians heeded our guidance on regular therapeutic monitoring and dose adjustments. The therapeutic target was achieved in 66.6% of cases, with a Cmax/CMI target attainment rate of 44.4%.The use of individualized initial doses of gentamicin, combined with Therapeutic Drug Monitoring based on PK/PD parameters, enhances the chances of therapeutic success and restricts the emergence of bacterial resistance.