Am. J. Respir. Crit. Care Med., Vol 154, No. 1, 07 1996, 82-90.
Benefits of the low pressure multichannel endotracheal ventilation
D Pinquier, D Pavlovic, G Boussignac, M Aubier and F Beaufils
Service de Reanimation Pediatrique, Hopital Robert Debre, Paris, France.
Mechanical ventilation using a modified endotracheal tube, allowing bypass
and washout of the endotracheal dead space (McETV), was compared with
conventional controlled mechanical ventilation (CMV) in healthy and in
surfactant-depleted rabbits. In healthy animals, shifting from CMV to McETV
led to an increase in PaO2 (89 +/- 16 versus 104 +/- 13 mm Hg; p < 0.05)
and a decrease in PaCO2 (41.5 +/- 3 versus 30 +/- 3 mm Hg; p < 0.05). As
a result of reducing the peak inspiratory pressure (PIP) from 21 +/- 2 to
12 +/- 2 cm H2O (p < 0.05), it was possible in McETV mode to maintain
comparable ventilation to that achieved by CMV. In surfactant-depleted
animals, compared with CMV, McETV produced a rise in PaO2 without change in
thoracic volume (from 100 +/- 40 to 150 +/- 60 mm Hg, p < 0.05) and a
fall in PaCO2 (from 46 +/- 5 to 37 +/- 4 mm Hg, p < 0.05). After 4 h of
ventilation, the surfactant-depleted animals from the CMV group developed
thoracic overdistension quicker (at hour 1, p < 0.05) and, consequently,
more animals died from pneumothorax compared with the McETV group (five
versus two). We concluded that McETV ensured adequate gas exchanges with
lower insufflation pressures and could diminish positive pressure
ventilation- induced injury.
