title: Rocuronium attenuates oculocardiac reflex during squint surgery in children anesthetized with halothane and nitrous oxide.
abstract: BACKGROUND
  The oculocardiac reflex (OCR) may be activated during squint surgery. The aim of this study was to test whether rocuronium 0.4 mg kg(-1) could reduce the frequency of OCR, and also whether a single dose of succinylcholine 1 mg kg(-1) could affect the frequency of OCR during anesthesia with halothane in a nitrous oxide/oxygen mixture.
  
  
  METHODS
  A total of 161 ASA I children, 3-10 years old, undergoing elective surgery of the medial rectus muscle (MRM) were randomly assigned to three groups. Group R (n = 51), received 0.4 mg kg(-1) of rocuronium intravenously before endotracheal intubation. Group S (n = 58) received 1 mg kg(-1) of succinylcholine. Group C (controls, n = 52) received no relaxant. Oculocardiac reflex was defined as a reduction in heart rate (HR) > or = 15% and/or the appearance of any other arrhythmias, during manipulation of the MRM. Analysis of variance (anova), chi-squared, Kruskal-Wallis, and Student's t-tests were used for statistical analysis; P< 0.05 was considered statistically significant.
  
  
  RESULTS
  In group R, OCR occurred in 15/51 (29%) of children, in group S in 31/58 (53%), and in group C in 23/52 (44%) (chi2 = 6.46, P = 0.049). In group R, the incidence of arrhythmias such as nodal rhythms, supraventricular and ventricular premature beats was 6%, compared with 22% in group S and 19% in group C (chi2 = 6.01, P = 0.040). However, there was no reduction in the occurrence of bradycardia (chi2 = 0.16, P = 0.924).
  
  
  CONCLUSIONS
  Rocuronium reduced the frequency of OCR, mainly by reducing the incidence of supraventricular and ventricular premature beats.
authors.affiliation: Department of Anesthesiology and Intensive Care, University Hospital Split, Split, Croatia.
authors.forename: N
authors.initials: N
authors.lastname: Karanovic
authors.forename: M
authors.initials: M
authors.lastname: Jukic
authors.forename: M
authors.initials: M
authors.lastname: Carev
authors.forename: G
authors.initials: G
authors.lastname: Kardum
authors.forename: Z
authors.initials: Z
authors.lastname: Dogas
mesh_terms: D000732:Androstanols / Q000627:therapeutic use*; D000769:Anesthesia, Inhalation; D018685:Anesthetics, Inhalation; D001145:Arrhythmias, Cardiac / Q000139:chemically induced / Q000503:physiopathology; D002648:Child; D002675:Child, Preschool; D004562:Electrocardiography / Q000187:drug effects; D005260:Female; D006221:Halothane; D006339:Heart Rate / Q000187:drug effects; D006801:Humans; D007431:Intraoperative Complications / Q000139:chemically induced / Q000453:epidemiology / Q000503:physiopathology / Q000517:prevention & control*; D008297:Male; D009467:Neuromuscular Depolarizing Agents / Q000494:pharmacology; D003473:Neuromuscular Nondepolarizing Agents / Q000627:therapeutic use*; D009609:Nitrous Oxide; D009801:Oculomotor Muscles / Q000601:surgery; D013508:Ophthalmologic Surgical Procedures; D012024:Reflex, Oculocardiac / Q000187:drug effects*; D000077123:Rocuronium; D013285:Strabismus / Q000601:surgery*; D013390:Succinylcholine / Q000494:pharmacology
chemical_list: D000732:Androstanols; D018685:Anesthetics, Inhalation; D009467:Neuromuscular Depolarizing Agents; D003473:Neuromuscular Nondepolarizing Agents; D013390:Succinylcholine; D009609:Nitrous Oxide; D006221:Halothane; D000077123:Rocuronium