Pupillary light response after used neuromuscular blockade agents of succinylcholine or rocuronium

Recently, the researchers investigated whether Succinylcholine or Rocuronium (short-acting neuromuscular blocking agents) affected pupillary response or dilation of the pupil to the light, because theoretically this agents could impairs pupillary response.

The researchers concern about this possibility, because pupillary response is mediated by ganglionic nicotinic receptors which are subject to inhibition by depolarizing and nondepolarizing neuromuscular blockers.

Reported in Annals of Emergency Medicine on January 8, 2011, the authors of the study, Dr. David A. Caro from University of Florida College of Medicine-Jacksonville, Jacksonville, Florid, and colleagues found that succinylcholine or rocuronium do not impair pupillary response to light.

The study involved 67 patients which were 91% (67 patients) received succinylcholine and remain received rocuronium had preserved pupillary responses to light after neuromuscular blocakde.

Despite the limitations of the study included small and lack of sample size, different design of the study between two neuromuscular blocking agents, lack of randomization, and lack of physician blinding to the medication used, the authors conclude, “Our study supports the clinical utility of pupillary after rapid sequence intubation. The absence of pupillary response may indicate the presence of a significant neurologic lesion.”

However, the authors add, “Clinicians should verify the presence of pupillary response after rapid sequence intubation. The absence of pupillary response may indicate the presence of a significant neurologic lesion.”