Critical Care Medicine-Renal, Electrolyte and Acid Base Disorders>>>>>Drug Dosing in Renal Failure
Question 2#

Which of the following statements is correct with regards to drug dosing in chronic kidney disease (CKD)?

A. The loading dose of vancomycin needs to be decreased in patients with chronic renal failure
B. The induction dose of propofol for intubation in CKD patients must be significantly reduced
C. The dose of tobramycin needs to be reduced in patients with CKD
D. The duration of action of cisatracurium is not prolonged in renal failure because of its Hoffman elimination

Correct Answer is D

Comment:

Correct Answer: D

Vancomycin is nephrotoxic, especially in patients with chronic renal failure. The loading dose is not affected as it is imperative to reach the target concentration as soon as possible. However, reduction in maintenance dose or longer dosing intervals may be necessary in patients in renal insufficiency.

With an initial intravenous bolus of propofol, the termination of central nervous system effects depends primarily on the redistribution of the drug from the central compartment to the peripheral compartments. Therefore, the induction dose of propofol is unchanged in CKD patients. Cisatracurium undergoes degradation by Hoffman elimination and ester hydrolysis, both independent of renal function. Therefore, its dose does not need to be adjusted in renal failure.

References:

1. Barash PG. Clinical Anesthesia. 7th ed. Philadelphia, PA: Wolters Kluwer Health/Lippincott Williams & Wilkins; 2013:1410-1411.
2. Salem MM. “Pathophysiology of hypertension in renal failure.” Semin Nephrol. 2002;22(1):17-26.
3. Thomas R, Kanso A, Sedor JR. “Chronic kidney disease and its complications.” Primary care. 2008;35(2):329, vii.