title: Bench study of a new device to display and maintain stable artificial airway cuff pressure.
abstract: BACKGROUND
  Artificial airway cuff pressure should be maintained within a narrow range. Excessive cuff pressure presents a risk of tracheal damage and stenosis. Insufficient cuff pressure adds the risk of secretion leak past the cuff, tidal-volume leakage, and accidental extubation.  The available cuff-inflation devices do not address these problems.
  
  
  OBJECTIVE
  In the laboratory I developed and evaluated a new cuff-inflation device that continuously displays the cuff pressure and maintains stable cuff pressure.
  
  
  METHODS
  The cuff-inflation device evaluation included: test  the manometer accuracy; compare the displayed pressure to the pressure delivered to the pilot balloon; determine the device's response to cuff-pressure changes with the addition of 5 mL or 10 mL of air after achieving a 30 cm H(2)O baseline; measure the V(T) leak in an intubated  artificial trachea by comparing the device results to benchmark measurements; and determine the stability of baseline cuff pressure during routine cuff checks.
  
  
  RESULTS
  The mean ± SD bias and precision of device's display, compared to the calibration analyzer, was 1.3 ± 2.6 cm  H(2)O. The pressure delivered by the cuff-inflation device's gas-sampling line to the pilot balloon was equal to the pressure displayed by the cuff-inflation device. With the cuff-inflation device the cuff pressure was unchanged, compared to baseline, after adding 5 mL or 10 mL of  air. With 2 current cuff methods, cuff pressure increased to means exceeding 160 cm H(2)O and 300 cm H(2)O, respectively. Compared to the benchmark, the difference in exhaled V(T) mean ± SD bias and precision were: cuff-inflation device 1.4 ± 4.8 mL,  and syringe-inflation method 2.4 ± 6.2 mL. Representing a single cuff pressure check, disconnecting the endotracheal-tube pilot balloon from the cuff-inflation device's gas-sampling line and then reconnecting it had no effect on baseline cuff pressure at 2 seconds or 60 seconds.
  
  
  CONCLUSIONS
  The cuff-inflation device demonstrated possible improvements over available cuff-inflation devices and cuff-pressure-control methods.
authors.affiliation: Department of Respiratory Care, Tufts Medical Center, Boston, Massachusetts 02111, USA. whoward@tuftsmedicalcenter.org
authors.forename: William R
authors.initials: WR
authors.lastname: Howard
mesh_terms: D003251:Constriction, Pathologic; D003626:Data Display; D004867:Equipment Design; D006801:Humans; D007442:Intubation, Intratracheal / Q000295:instrumentation*; D008422:Materials Testing; D011312:Pressure; D012121:Respiration, Artificial; D014132:Trachea / Q000293:injuries / Q000473:pathology