Antibiotic dosing matters….especially while your patient is on dialysis!
- Inappropriate antimicrobial dosing is associated with higher mortality and the addition of continuous renal replacement therapy (CRRT) complicates matters further.
- The addition of CRRT requires further dosage adjustments to account for additional volume and interaction with the dialysis filter; however, specific medication data to make these adjustments is limited.
- After utilizing your local pharmacist and discussing dosing with them, here are some questions to consider while your patient is receiving CRRT:
- What is the pharmacologic properties of the medication and how they will alter the interaction with the CRRT
- Is the medication renally or hepatically cleared?
- Is the medication highly protein bound or free and active and is the medication hydrophilic or lipophilic?
- What is the molecular size of the medication (i.e., how readily dialysable it will be)?
- Is the antimicrobial time dependent (requiring an adequate concentration over the dosing period) or concentration dependent (requiring an adequate peak level) in its action?
- Can you send a drug level to assess the dosing strategy (e.g., gentamicin, vancomycin, etc.)?
References
- Fissell WH. Antimicrobial Dosing in Acute Renal Replacement. Advances in Chronic Kidney Disease. 2013;20(1):85-93.
- Lewis SJ, Mueller BA. Antibiotic Dosing in Patients With Acute Kidney Injury. Journal of Intensive Care Medicine. 2016;31(3):164-176.
- Scoville BA, Mueller BA. Medication dosing in critically ill patients with acute kidney injury treated with renal replacement therapy. Am J Kidney Dis. 2013;61(3):490-500.