title: Neopuff T-piece mask resuscitator: is mask leak related to watching the pressure dial?
abstract: OBJECTIVE
  The aim of the study is to compare mask leak and delivered ventilation during Neopuff (NP) mask ventilation in two modes: (i) with NP pressure dial hidden and resuscitator watching chest wall (CW) rise with, (ii) CW movement hidden and resuscitator watching NP pressure dial.
  
  
  METHODS
  Thirty-six participants gave mask ventilation to a modified manikin designed to measure mask leak and delivered ventilation for two minutes in each mode randomly assigned. Paired t-tests were used to analyse differences in mean values. Linear regression was used to determine the association of mask leak with delivered ventilation.
  
  
  RESULTS
  Of 7277 inflations analysed, 3621 were observing chest wall mode (CWM) and 3656 observing NP mode (NPM). Mask leak was similar between the groups; 31.6% for CWM and 31.5% (p = 0.56) for NPM. There were no significant differences in airways pressures and expired tidal volumes (TVe) between modes. Mask leak was strongly associated with TVe (R = -0.86 p < 0.0001) and with peak inspiratory pressure (PIP) (R = -0.51 p < 0.0001). TVe was associated with PIP (R = 0.51 p < 0.0001).
  
  
  CONCLUSIONS
  This study provides reassurance that NP mask leak is not greater when resuscitators watch the NP pressure dial. Mask leak is related to TVe. Mask ventilation training with manikins should include tidal volume measurements.
authors.affiliation: Nepean Hospital Sydney West Area Health Service, Sydney, Australia. mark.tracy@ozemail.com.au
authors.forename: Mark B
authors.initials: MB
authors.lastname: Tracy
authors.forename: J
authors.initials: J
authors.lastname: Klimek
authors.forename: V
authors.initials: V
authors.lastname: Shingde
authors.forename: M
authors.initials: M
authors.lastname: Hinder
authors.forename: R
authors.initials: R
authors.lastname: Maheshwari
authors.forename: S K
authors.initials: SK
authors.lastname: Tracy
mesh_terms: D016887:Cardiopulmonary Resuscitation / Q000295:instrumentation* / Q000379:methods; D018592:Cross-Over Studies; D019544:Equipment Failure Analysis; D006801:Humans; D007231:Infant, Newborn; D016014:Linear Models; D008348:Manikins; D008397:Masks; D011175:Positive-Pressure Respiration / Q000295:instrumentation* / Q000379:methods; D011446:Prospective Studies; D015656:Respiratory Mechanics; D013990:Tidal Volume