title: The Microcuff tube allows a longer time interval until unsafe cuff pressures are reached in children.
abstract: OBJECTIVE
  To compare cuff pressures during nitrous oxide exposure in the new Microcuff pediatric tracheal tube (MPT) with ultrathin high volume - low pressure polyurethane cuff to a tube with a standard polyvinyl chloride (PVC) cuff.
  
  
  METHODS
  With approval of the local Ethics Committee, 30 pediatric patients requiring tracheal intubation [tube size internal diameter (ID) 4.0 mm, or ID 7.0 mm) were included. Patients were randomly divided in three groups: A) MPT, baseline cuff pressure 20 cm H(2)O; B) PVC, baseline cuff pressure 20 cm H(2)O; and C) MPT, baseline cuff pressure set to sealing pressure. Anesthesia technique and ventilator settings were standardized. The time required for cuff pressure to increase to 25 cm H(2)O was recorded and pressure reduced to baseline. The number of gas removals required during the first hour was noted. Data are median (range). Groups were compared by the Kruskal-Wallis test (P < 0.05).
  
  
  RESULTS
  There were no differences between groups in patient characteristics. PVC and MPT cuffs inflated to a baseline pressure of 20 cm H(2)O were similar regarding the time to first removal of gas [A: nine minutes (4-24), B: eight minutes (4-46)], and number of removals required [A: four (2-6), B: three (1-5)]. In MPT with baseline pressure set to sealing pressure [10 cm H(2)O (8-14)] time to first gas removal and number of removals were significantly less (P < 0.05).
  
  
  CONCLUSIONS
  When baseline inflation pressure was set at 20 cm H(2)O, cuff pressure increased similarly in MPT and PVC tubes. When inflated just to sealing pressure, the MPT allowed a longer time interval until the upper limit of 25 cm H(2)O was reached.
authors.affiliation: Department of Anesthesia, University Children's Hospital, Steinwiesstrasse 75, CH-8032 Zurich, Switzerland. alex.dullenkopf@kispi.unizh.ch
authors.forename: Alexander
authors.initials: A
authors.lastname: Dullenkopf
authors.forename: Andreas
authors.initials: A
authors.lastname: Gerber
authors.forename: Markus
authors.initials: M
authors.lastname: Weiss
mesh_terms: D000293:Adolescent; D018685:Anesthetics, Inhalation / Q000008:administration & dosage; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D007442:Intubation, Intratracheal / Q000009:adverse effects* / Q000295:instrumentation*; D008297:Male; D009609:Nitrous Oxide / Q000008:administration & dosage; D011140:Polyurethanes; D011143:Polyvinyl Chloride; D011312:Pressure / Q000009:adverse effects; D018709:Statistics, Nonparametric; D013997:Time Factors
chemical_list: D018685:Anesthetics, Inhalation; D011140:Polyurethanes; D011143:Polyvinyl Chloride; D009609:Nitrous Oxide