title: Endotracheal tube size estimation for children with pathological short stature.
abstract: OBJECTIVE
  To compare length-based estimates of endotracheal tube (ETT) size and age-based estimates with anesthesiologist-selected ideal ETT size in children with medical conditions affecting normal growth, known as pathological short stature (PSS).
  
  
  METHODS
  We conducted a retrospective review of the anesthesia database of all children undergoing tracheal intubation for any surgical procedure during a 3-year period. The anesthesiologist-selected ideal ETT size was defined as that selected and successfully used throughout the case under the supervision of a board-certified pediatric anesthesiologist. Objective criteria, such as leak test and adequate oxygenation/ventilation, were used to validate the appropriateness of the ETT chosen. For analysis, the children were classified as normal length for age versus PSS, defined as less than 5% length for age on the Centers for Disease Control and Prevention growth chart. The proportions of clinically relevant predicted ETTs, within +/-0.5 mm of the anesthesiologist-selected ideal ETT size, based on both age- and length-based formulas for each group were then compared.
  
  
  RESULTS
  Five thousand one hundred seventy-five patient records were analyzed. In children with normal stature, age-predicted ETT size was within the clinically relevant range in 89.8% (95% confidence interval [CI], 88.9%-90.7%), and length-predicted ETT size was within the clinically relevant range in 92.8% (95% CI, 92.0%-93.6%). In children with PSS, age-predicted ETT size was within the clinically relevant range in 86.6% (95% CI, 84.3%-89.0%), and length-predicted ETT size was within the clinically relevant range in 92.2% (95% CI, 90.3%-94.0%). The correlation coefficient for age to anesthesiologist-selected ideal ETT size was strong for both normal and PSS patients (r = 0.91 and r = 0.93, respectively). Length was also highly correlated to actual ETT size used for both groups (r = .91).
  
  
  CONCLUSIONS
  Length-based prediction of ETT size is at least as accurate as age-based estimation in both normal and pathologically short children.
authors.affiliation: Division of Pediatric Emergency Medicine, The Children's Hospital of Philadelphia, Philadelphia, PA, USA. rdaugher@nemours.org
authors.forename: Reza James
authors.initials: RJ
authors.lastname: Daugherty
authors.forename: Vinay
authors.initials: V
authors.lastname: Nadkarni
authors.forename: Bruce Randall
authors.initials: BR
authors.lastname: Brenn
mesh_terms: D000367:Age Factors; D000776:Anesthesiology / Q000295:instrumentation*; D000886:Anthropometry; D001827:Body Height; D002648:Child; D002675:Child, Preschool; D003430:Cross-Sectional Studies; D003625:Data Collection; D004392:Dwarfism / Q000628:therapy*; D004867:Equipment Design; D005260:Female; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D007442:Intubation, Intratracheal / Q000295:instrumentation*; D008297:Male; D010009:Osteochondrodysplasias / Q000628:therapy; D010372:Pediatrics; D012189:Retrospective Studies; D013514:Surgical Procedures, Operative / Q000706:statistics & numerical data