Ventilator-delivered mask ventilation compared with three standard methods of mask ventilation in a manikin model.
BACKGROUND
Little is known regarding the variations in effective ventilation during bag and mask resuscitation with standard methods compared with that delivered by ventilator-delivered mask ventilation (VDMV).


OBJECTIVE
To measure the variations in delivered airway pressure, tidal volume (TV), minute ventilation (MV) and inspiratory time during a 3-min period of mask ventilation comparing VDMV with three commonly used hand-delivered methods of bag and mask ventilation: Laerdal self-inflating bag (SIB); anaesthetic bag and T-piece Neopuff.


METHODS
A modified resuscitation manikin was used to measure variation in mechanical ventilation during 3-min periods of mask ventilation. Thirty-six experienced practitioners gave positive pressure mask ventilation targeting acceptable chest wall movement with a rate of 60 inflations/min and when pressures could be targeted or set, a peak inspiratory pressure (PIP) of 18 cm water, positive end-expiratory pressure (PEEP) of 5 cm water, for 3 min with each of the four mask ventilation methods. Each mode was randomly sequenced.


RESULTS
A total of 21 136 inflations were recorded and analysed. VDMV achieved PIP and PEEP closest to that targeted and significantly lower variation in all measured parameters (p<0.001) other than with PIP. SIB delivered TV and MV over twice that delivered by VDMV and Neopuff.


CONCLUSIONS
During 3-min periods of mask ventilation on a manikin, VDMV produced the least variation in delivered ventilation. SIB produced wide variation and unacceptably high TV and MV in experienced hands.
Department of Neonatology, Nepean Neonatal Intensive Care Unit, Nepean Hospital SWAHS, Derby Street Kingswood 2747, Sydney, Australia. mark.tracy@ozemail.com.au
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MB
Tracy
J
J
Klimek
H
H
Coughtrey
V
V
Shingde
G
G
Ponnampalam
M
M
Hinder
R
R
Maheshwari
S K
SK
Tracy
D000403:Airway Resistance / Q000502:physiology; D006801:Humans; D007231:Infant, Newborn; D001239:Inhalation / Q000502:physiology; D015931:Intensive Care, Neonatal / Q000379:methods*; D008348:Manikins; D008397:Masks; D011175:Positive-Pressure Respiration; D012121:Respiration, Artificial / Q000295:instrumentation / Q000379:methods*; D013990:Tidal Volume / Q000502:physiology; D012122:Ventilators, Mechanical