title: [Neostigmine-induced neuromuscular blockade in the corrugator supercilii muscle].
abstract: OBJECTIVE
  To investigate whether a single dose of neostigmine, administered when the adductor pollicis muscle presents 2 twitches in train-of-four (TOF) stimulation, can reduce the TOF ratio in the corrugator supercilii muscle.
  
  
  METHODS
  We designed a case-control study of patients between 18 and 65 years of age classified ASA 1-2. We used 2 accelerometers--1 for the cubital nerve/thumb adductor muscle and 1 for the facial nerve/corrugator supercilii muscle. Neuromuscular blockade was induced with 0.6 mg x kg(-1) of rocuronium, and 40 microg x kg(-1) of neostigmine was administered at the third twitch in the TOF in the thumb adductor. If the TOF ratio in the corrugator supercilii fell by 10% or more at that time, the patient was classified as a case. We recorded the age, sex, weight, height, body mass index, duration of the procedure, and TOF ratio in the corrugator supercilii muscle when the neostigmine was administered.
  
  
  RESULTS
  Ten cases and 10 controls were enrolled. No significant differences between cases and controls were found in any variables except the mean (SD) TOF ratio in the corrugator supercilii muscle: 70.9% (17.8%) in cases and 35.3% (7.8%) in controls (P < .001).
  
  
  CONCLUSIONS
  In our patients, administration of neostigmine after the appearance of the third twitch in TOF stimulation of the thumb adductor was associated with a reduction in the TOF ratio in the corrugator supercilii. The similarity between blockades of the corrugator muscle, the diaphragm, and the larynx is of clinical interest.
authors.affiliation: Servicio de Anestesiología y Reanimación, Hospital Universitario 12 de Octubre. Madrid. fmartinezt.hdoc@salud.madrid.org
authors.forename: F
authors.initials: F
authors.lastname: Martínez Torrente
authors.forename: A J
authors.initials: AJ
authors.lastname: Carrascosa Fernández
authors.forename: M C
authors.initials: MC
authors.lastname: García Miranda
authors.forename: F
authors.initials: F
authors.lastname: Pérez-Cerdá Silvestre
authors.forename: F
authors.initials: F
authors.lastname: Gilsanz Rodríguez
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D016022:Case-Control Studies; D002800:Cholinesterase Inhibitors / Q000494:pharmacology*; D005152:Facial Muscles / Q000187:drug effects*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009388:Neostigmine / Q000494:pharmacology*; D019148:Neuromuscular Blockade; D055815:Young Adult
chemical_list: D002800:Cholinesterase Inhibitors; D009388:Neostigmine