Concentration of rocuronium in cerebrospinal fluid of patients undergoing cerebral aneurysm clipping

Background. This study assessed the concentration of rocuroniumin the cerebrospinal fluid (CSF) of patients undergoing cerebralaneurysm clipping, and investigated whether the mode of administration(single bolus vs continuous infusion) influenced the CSF concentration. Methods. Twenty patients with subarachnoid haemorrhage wererandomly allocated to receive a bolus dose (bolus group), ora bolus followed by a continuous infusion of rocuronium (infusiongroup) (n=10 for each group). Arterial blood and ventricularCSF were sampled 2 h after the rocuronium bolus. Samples wereanalysed by liquid chromatography electrospray ionization-tandemmass spectrometry. Results. Rocuronium could be detected in all the CSF samples.The mean (range) CSF concentration was 2.2 (0.9–4.6) ngml^–1 in the bolus group and 12.4 (2.4–34.6) ng ml^–1in the infusion group; P<0.01. Conclusions. This study demonstrated that rocuronium, normallynot considered to cross the blood–brain barrier, is regularlyfound in the CSF of patients undergoing cerebral clipping; continuousinfusion of the drug led to higher plasma and CSF concentrationsthan after a single bolus dose. Br J Anaesth 2004; 92: 419–21