Neuromuscular blocking agents in CRF
Clinical - Renal/Urine/Electrolytes, Pharmacology
Rocuronium: elimination half-time increased by 37%. Both volume of distribution and plasma clearance are increased. That said,according to Miller, “the duration of action of single and repeated doses, though, is not significantly affected .
Vecuronium: elimination half-time increased by 24-56%. Vecuronium is primarily eliminated via hepatic mechanisms, however, its elimination half-life is still increased in patients with renal failure. Duration of action appears to be both longer and more variable in patients with renal failure. Note that 3-desacetylvecuronium, the principal metabolite of vecuronium, has 80% of the neuromuscular blocking activity of its parent compound and may prolong paralysis.
Pancuronium: elimination half-time increased by 97%. Duration of action prolonged.
Atracurium: duration of action unaffected by renal failure. Hofmann elimination and ester hydrolysis account for 50% of total clearance. Elimination half-life of neurotoxic metabolite laudanosine increases in renal failure, although this may not be clinically relevant
cis-Atracurium: duration of action is not prolonged. Hofmann elimination accounts for 77% of total clearance, renal excretion accounts for 16%
Paralytics in Setting of Renal Failure
- Rocuronium: t 1/2 increased 37%, may not translate into increased duration
- Vecuronium: t 1/2 increased 24-56%, duration longer and more variable
- Pancuronium: t 1/2 increased 97%, prolonged duration of action