title: The effect of cisatracurium and rocuronium on lung function in anesthetized children.
abstract: BACKGROUND
  Neuromuscular blocking drugs have been implicated in intraoperative bronchoconstrictive episodes. We examined the effects of clinically relevant doses of cisatracurium and rocuronium on the lung mechanics of pediatric subjects. We hypothesized that cisatracurium and rocuronium would have bronchoconstrictive effects.
  
  
  METHODS
  We studied ASA physical status I and II pediatric subjects having elective dental or urological procedures, requiring general anesthesia with endotracheal intubations with either cisatracurium or rocuronium. Pulmonary function tests were performed before and after neuromuscular blocking drug dosing and again after albuterol administration. Using forced deflation and passive deflation techniques, forced vital capacity (FVC) and maximum expiratory flow rate at 10% (MEF10) of FVC were obtained. Fractional changes from the baseline were used to compare subjects. Changes in MEF10 of >30% were considered clinically significant. A Shapiro-Wilk test, paired t test, and Wilcoxon rank sum test were used to analyze the data.
  
  
  RESULTS
  Twenty-five subjects (median age = 5.25 years; range = 9 months-9.9 years) were studied; 12 subjects received cisatracurium and 13 subjects received rocuronium. Data are shown as mean proportional change ± SD or, in the case of not normally distributed, median proportional change (first, third quartile) with P values. In the cisatracurium group, there were no differences between baseline and postneuromuscular blocker administration in the fractional change from the baselines of FVC (1.00 ± 0.04, P = 0.5), but there was a significant decrease in MEF10 (0.80 ± 0.18, P = 0.002). In the rocuronium group, there were small yet significant decreases of FVC (0.99 [first quartile 0.97, third quartile 1], P = 0.02) and significant decreases in MEF10 (0.78 ± 0.26, P = 0.008). After administration of albuterol in the cisatracurium group, FVC increased slightly but significantly from baseline values (1.02 ± 0.02, P = 0.005). MEF10 increased significantly beyond baseline values (1.24 ± 0.43, P =0.04). In the rocuronium group, there were also significant differences between baseline and postalbuterol administration from the baseline value of FVC (1.02 ± 0.02, P = 0.004) and MEF10 (1.23 ± 0.29, P = 0.01).
  
  
  CONCLUSIONS
  At clinically relevant doses, both cisatracurium and rocuronium caused changes in lung function, indicating constriction of smaller airways. In general, these changes were mild and not clinically detectable. However, in the rocuronium group, 3 of 13 patients showed more noticeable decreases in MEF10 (≤50%), demonstrating the potential for significant broncho-bronchiolar constriction in susceptible patients.
authors.affiliation: From the *Department of Anesthesiology, University of Pittsburgh School of Medicine, Children's Hospital of Pittsburgh of UPMC, Pittsburgh, Pennsylvania; †Department of Anesthesiology, Duke Children's Hospital, Duke University Medical Center, Durham, North Carolina; and ‡Department of Pediatrics, University of Pittsburgh School of Medicine Division of Pulmonology, Children's Hospital of Pittsburgh, Pittsburgh, Pennsylvania.
authors.forename: Charles I
authors.initials: CI
authors.lastname: Yang
authors.forename: Gavin F
authors.initials: GF
authors.lastname: Fine
authors.forename: Edmund H
authors.initials: EH
authors.lastname: Jooste
authors.forename: Rebecca
authors.initials: R
authors.lastname: Mutich
authors.forename: Stephen A
authors.initials: SA
authors.lastname: Walczak
authors.forename: Etsuro K
authors.initials: EK
authors.lastname: Motoyama
mesh_terms: D000367:Age Factors; D000732:Androstanols / Q000009:adverse effects*; D000768:Anesthesia, General; D001279:Atracurium / Q000009:adverse effects / Q000031:analogs & derivatives*; D016084:Bronchoconstriction / Q000187:drug effects*; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D007442:Intubation, Intratracheal; D008168:Lung / Q000187:drug effects* / Q000503:physiopathology; D008297:Male; D008448:Maximal Expiratory Flow Rate / Q000187:drug effects; D003473:Neuromuscular Nondepolarizing Agents / Q000009:adverse effects*; D010414:Pennsylvania; D012307:Risk Factors; D000077123:Rocuronium; D014797:Vital Capacity / Q000187:drug effects
chemical_list: D000732:Androstanols; D003473:Neuromuscular Nondepolarizing Agents; D001279:Atracurium; C101584:cisatracurium; D000077123:Rocuronium