Carbapenem Renal Dose Discordance and Acute Kidney Injury in the Intensive Care Unit: A Retrospective Cohort Study

Background: Renal function changes rapidly in the intensive care unit (ICU), and carbapenem dosing above renal-adjusted recommendations is a potentially preventable medication safety issue. Objective: To evaluate the association between carbapenem renal dose discordance and acute kidney injury (AKI); treatment failure was exploratory. Methods: This ethics-approved retrospective cohort included adults receiving carbapenems for at least 48 hours in a Vietnamese hospital ICU (January 2024-April 2026). Discordance was at least 1 day above renal-adjusted recommendations based on estimated Cockcroft-Gault creatinine clearance and clinical indication. Kidney Disease: Improving Global Outcomes criteria defined AKI. Robust Poisson regression estimated adjusted risk ratios (aRRs). Matched outcome models additionally adjusted for Glasgow Coma Scale category and septic shock. A post hoc Bonferroni threshold of α = .003125 was applied. Results: Of 490 patients, 78 (15.9%) had discordant dosing. Acute kidney injury occurred in 28/78 (35.9%) with discordant dosing versus 18/412 (4.4%) with concordant dosing. Discordance was associated with AKI in the primary analysis (aRR, 8.061; 95% confidence interval [CI], 4.135-15.714; P < .001) and among 68 matched pairs (aRR, 5.937; 95% CI, 2.112-16.694; P = .001). Associations with treatment failure did not meet the corrected threshold in the primary analysis (aRR, 1.586; 95% CI, 1.023-2.458; P = .039) or among matched pairs (aRR, 1.164; 95% CI, 0.723-1.875; P = .532). Conclusions: Carbapenem renal dose discordance was associated with AKI, although causation cannot be established. Daily renal dose review by pharmacists is a practical medication safety target that warrants prospective evaluation.