title: Comparison of age-based and height-based formula for tracheal tube size in cardiac children.
abstract: OBJECTIVE
  To compare the effectiveness of age-based formula (ABF) and height-based formula (HBF) for pediatric cardiac patients, including patients with failure to thrive (FTT).
  
  
  METHODS
  In a retrospective study of 260 cardiac patients that included those with failure to thrive, aged 2 to 7 years was done. The actual uncuffed endotracheal tube (ETT) size was compared with the predicted one, using both the ABF [ID (mm) = age (years)/4 + 4] and the HBF [ID (mm) = height (cm)/30 + 2].
  
  
  RESULTS
  ABF and HBF correctly predicted 50.8% and 50.4% of ETT sizes (p = 1.0), whereas three sizes of tubes (one above and one below the predicted size) cover 95.8% and 93.5% of the patients, respectively (p = 0.24). In patients with FTT, both the ABF and HBF correctly predicted 56.6% of ETT sizes.
  
  
  CONCLUSIONS
  Age- and height-based formula for estimating tube size in cardio-surgical children is equivalent and independent of physical development. Age-based formula as the simple method can be recommended. The availability of three tube sizes (one smaller one larger than estimated) should be ensured.
authors.affiliation: * Department ofAnesthesiology, Faculty of Medicine Siriraj Hospital, Mahidol University, Bangkok, Thailand. siscu@mahidol.ac.th
authors.forename: Saowapark
authors.initials: S
authors.lastname: Chumpathong
authors.forename: Saipin
authors.initials: S
authors.lastname: Muangman
authors.forename: Benno
authors.initials: B
authors.lastname: von Bormann
authors.forename: Kamheang
authors.initials: K
authors.lastname: Vacharaksa
mesh_terms: D000367:Age Factors; D000465:Algorithms; D001827:Body Height; D002648:Child; D002675:Child, Preschool; D005260:Female; D006331:Heart Diseases / Q000628:therapy*; D006801:Humans; D007442:Intubation, Intratracheal / Q000295:instrumentation*; D008297:Male; D012189:Retrospective Studies