Abstract
Purpose
The aim of this study was to investigate whether monitoring neuromuscular block at the masseter muscle (MM) would allow faster tracheal intubation when compared with that at the adductor pollicis muscle (APM).
Methods
Twenty female patients undergoing gynecological surgery were enrolled into this study. Immediately after inducing anesthesia with fentanyl and propofol, both the left masseter and ulnar nerves were stimulated in a 2 Hz train-of-four (TOF) mode using peripheral nerve stimulators. Contractions of the MM were felt with the anesthesiologist’s left hand lifting the patient’s jaw and holding an anesthesia facemask, while those of the APM were visually observed. Immediately after the contracting responses of the muscles were confirmed, all of the patients received an iv bolus of vecuronium 0.1 mg kg−1. Onset times after vecuronium were defined as the duration until the contractions became impalpable at the MM or invisible at the APM. When the contraction of the MM could no longer be felt, the conditions for laryngoscopy and tracheal intubation were assessed.
Results
Onset time evaluated tactually at the MM (mean ± SD, 108.4 ± 27.7 s) was significantly shorter than that evaluated visually at the APM (181.2 ± 32.1 s, P < 0.0001). The intubating conditions for all patients were graded as either excellent or good.
Conclusion
Tactual evaluation of muscle paralysis of the MM during induction of anesthesia is clinically useful since it leads to faster tracheal intubation.
This is a preview of subscription content, log in via an institution to check access.
Similar content being viewed by others
References
Meistelman C, Plaud B, Donati F. Rocuronium (ORG 9426) neuromuscular blockade at the adductor muscles of the larynx and adductor pollicis in humans. Can J Anaesth. 1992;39:665–9.
Cantineau JP, Porte F, d’Honneur G, Duvaldestin P. Neuromuscular effects of rocuronium on the diaphragm and adductor pollicis muscles in anesthetized patients. Anesthesiology. 1994;81:585–90.
Chauvin M, Lebrault C, Duvaldestin P. The neuromuscular blocking effect of vecuronium on the human diaphragm. Anesth Analg. 1987;66:117–22.
De Mey JC, De Baerdemaeker L, De Latt M, Rolly G. The onset of neuromuscular block at the masseter muscle as a predictor of optimal intubating conditions with rocuronium. Eur J Anaesthesiol. 1999;16:387–9.
de Rossi L, Preußler NP, Pühringer FK, Klein U. Onset of neuromuscular block at the masseter and adductor pollicis muscles following rocuronium or succinylcholine. Can J Anaesth. 1999;46:1133–7.
Smith CE, Donati F, Bevan DR. Differential effects of pancuronium on masseter and adductor pollicis muscles in humans. Anesthesiology. 1989;71:57–61.
Hemmerling TM, Donati F. Neuromuscular blockade at the larynx, the diaphragm and the corrugator supercilli muscle: a review. Can J Anaesth. 2003;50:779–94.
Fuchs-Buder T, Claudius C, Skovgaard LT, Eriksson LI, Mirakhur RK, Viby-Mogensen J. Good clinical research practice in pharmacodynamic studies of neuromuscular blocking agents II: the Stockholm revision. Acta Anaesthesiol Scand. 2007;51:789–808.
Plaud B, Proost JH, Wierda MKH, Barre J, Debaene B, Meistelman C. Pharmacokinetics and pharmacodynamics of rocuronium at the vocal cords and the adductor pollicis in humans. Clin Pharmacol Ther. 1995;58:185–91.
Nakamura Y, Torisu T, Noguchi K, Fujii H. Changes in masseter muscle blood flow during voluntary isometric contraction in humans. J Oral Rehabil. 2005;32:545–51.
Abdulatif M, El-Sanabary M. Blood flow and mivacurium-induced neuromuscular block at the orbicularis oculi and adductor pollicis muscles. Br J Anaesth. 1997;79:24–8.
Choi WW, Gergis SD, Sokoll MD. The effects of d-tubocurarine, pancuronium and atracurium on the responses of gastrocnemius and soleus muscles in the cat. Acta Anaesthesiol Scand. 1984;28:608–11.
Ibebunjo C, Srikant CB, Donati F. Morphological correlates of the differential responses of muscles to vecuronium. Br J Anaesth. 1999;83:284–91.
Rowlerson A, Raoul G, Daniel Y, Close J, Maurage CA, Ferri J, et al. Fiber-type differences in masseter muscle associated with different facial morphologies. Am J Orthod Dentofacial Orthop. 2005;127:37–46.
Helbo-Hansen HS, Bang U, Nielsen HK, Skovgaard LT. The accuracy of train-of-four monitoring at varying stimulating currents. Anesthesiology. 1992;76:199–203.
Acknowledgments
This study was performed using the institutional fund.
Author information
Authors and Affiliations
Corresponding author
About this article
Cite this article
Kitajima, O., Suzuki, T., Watanabe, N. et al. Monitoring masseter muscle evoked responses enables faster tracheal intubation. J Anesth 24, 173–176 (2010). https://doi.org/10.1007/s00540-009-0848-y
Received:
Accepted:
Published:
Issue Date:
DOI: https://doi.org/10.1007/s00540-009-0848-y