M Uhart1, B Leroy, P Maire, L Bourguignon. 1. Hospices Civils de Lyon, Groupement Hospitalier de Gériatrie, Service Pharmaceutique, Hôpital Antoine-Charial, 40 Avenue de la Table-de-Pierre, 69340 Francheville, France. mathieu.uhart@chu-lyon.fr
Abstract
OBJECTIVES: The authors had for objective to evaluate the applicability of AFSSAPS guidelines for aminoglycoside use to geriatric patients. METHODS: Theoretical doses and dosing regimens allowing reaching target concentrations in this population were calculated by applying a pharmacokinetic model to 30 geriatric patients treated by amikacin. RESULTS: The dose allowing reaching a maximum concentration of 60 mg/L was 1.217 mg on average. The time required to reach a blood concentration lower than or equal to 2.5mg/L was 62.5±70.4 hours. Forty-six percent of patients had a trough concentration greater than 2.5 mg/L, 48 hours after administration. For these patients, the time between critical minimum inhibitory concentration (MIC) and toxicity threshold concentration was 21.9±14.9 hours. CONCLUSION: Reaching a target concentration can be problematic in geriatric patients. It is frequently necessary to use dosing intervals greater than 48 hours. The effectiveness and safety of these regimens remain uncertain.
OBJECTIVES: The authors had for objective to evaluate the applicability of AFSSAPS guidelines for aminoglycoside use to geriatric patients. METHODS: Theoretical doses and dosing regimens allowing reaching target concentrations in this population were calculated by applying a pharmacokinetic model to 30 geriatric patients treated by amikacin. RESULTS: The dose allowing reaching a maximum concentration of 60 mg/L was 1.217 mg on average. The time required to reach a blood concentration lower than or equal to 2.5mg/L was 62.5±70.4 hours. Forty-six percent of patients had a trough concentration greater than 2.5 mg/L, 48 hours after administration. For these patients, the time between critical minimum inhibitory concentration (MIC) and toxicity threshold concentration was 21.9±14.9 hours. CONCLUSION: Reaching a target concentration can be problematic in geriatric patients. It is frequently necessary to use dosing intervals greater than 48 hours. The effectiveness and safety of these regimens remain uncertain.