title: Combitube: a study for proper use.
abstract: The esophageal-tracheal Combitube((R)) (ETC; Kendall-Sheridan Catheter Corp., Argyle, NY) is a new device designed for difficult airways and emergency intubation. The manufacturer recommends that the ETC model 37F SA be used in patients with a height of between 122 and 152 cm. The aim of this study was to evaluate whether ventilation is effective and reliable in patients taller than 152 cm by using the ETC 37F SA in the esophageal position. Also, we evaluated whether the airway protection is adequate and whether direct intubation of the trachea with the ETC inserted in the esophagus is possible. We studied 25 anesthetized, paralyzed adult patients, 150 to 180 cm in height. Methylene blue was given orally to all patients before anesthesia induction. Under direct vision, a ETC 37F SA was inserted in the esophagus of all patients. The pharyngeal balloon inflation volume was titrated to air leak and cuff pressures were measured. During surgery, a laryngoscope was inserted into the pharynx with the pharyngeal balloon deflated and the laryngoscopic view was evaluated by using the Cormack-Lehane scale. The presence of methylene blue in the hypopharynx was investigated by direct laryngoscopic vision. Ventilation was effective and reliable in all 25 patients who were 150 to 180 cm in height (average 169 +/- 7 cm). In addition, a direct relationship between the pharyngeal balloon volume and patient height was established (P < 0.05), by using linear regression models. The laryngoscopic view of the glottis was adequate to allow direct tracheal intubation. No trace of methylene blue was detected in the hypopharynx. The ETC Model 37F SA may be used in patients from 122 to 185 cm in height. The trachea could be directly intubated with the ETC in the esophageal position in patients with normal airways. The airway protection appears to be adequate.
  
  
  CONCLUSIONS
  The esophageal-tracheal Combitube((R)) Model 37F SA (Kendall-Sheridan Catheter Corp., Argyle, NY) may be used in patients from 122 to 185 cm in height. The trachea could be directly intubated with the Combitube((R)) in esophageal position in patients with normal airways. The airway protection appears to be adequate.
authors.affiliation: Intensive Care and Anesthesia Unit, Mutual de Seguridad Hospital C. CH.C., Santiago, Chile.
authors.forename: R M
authors.initials: RM
authors.lastname: Urtubia
authors.forename: C M
authors.initials: CM
authors.lastname: Aguila
authors.forename: M A
authors.initials: MA
authors.lastname: Cumsille
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001827:Body Height; D005260:Female; D006801:Humans; D007442:Intubation, Intratracheal / Q000295:instrumentation*; D007828:Laryngoscopy; D008297:Male; D008875:Middle Aged