Background: Augmented renal clearance refers to increased renal elimination of circulating solutes as compared with normal baseline and could lead to underexposure of frequently used renally eliminated antimicrobials. The primary objective was to assess the prevalence of augmented renal clearance in an adult non-critically ill surgery population. Besides, predictors for augmented renal clearance were investigated. A prospective observational single-center point prevalence study was conducted.
Methods: The measured creatinine clearance based on an 8-hour urinary collection was used as primary method for determining kidney function. Augmented renal clearance was defined as measured creatinine clearance of 130 mL/min per 1.73m² or greater. A Poisson regression model was applied to identify predictors for augmented renal clearance.
Results: Augmented renal clearance prevalence was 30% and 35% in 103 abdominal and 129 trauma surgery patients, respectively. Younger age (abdominal cohort: relative risk, 0.963 (95% CI, 0.949-0.978); trauma cohort: relative risk, 0.971 [95% CI, 0.960-0.983]) and also for trauma surgery patients, male sex (relative risk, 1.808 [95% CI, 1.026-3.185]) were found to be independent predictors for augmented renal clearance.
Conclusions: Augmented renal clearance is an underestimated phenomenon in adult non-critically ill surgery patients. Especially younger patients, and, in the subset of trauma surgery, males are prone to exhibit augmented renal clearance. Since augmented renal clearance is a risk factor for lower antimicrobial exposure, the impact of augmented renal clearance in relation to antimicrobial underexposure should be investigated in this population.
Level of evidence: Prognostic/epidemiological study, level III.