A new infant ventilator for normal and high-frequency ventilation: influence of tracheal tube on distal airway pressure during high-frequency ventilation.
A new infant ventilator for both normal and high-frequency ventilation is described. High pressure gas delivered via a jet in the breathing limb of a T-piece, in which there are no valves, drives respiratory fresh gas (RFG), supplied to the tracheal tube from any low pressure source, into the lungs. Observations on anesthetized rabbits showed that after setting up for a PaCO2 of 36 torr at 30 cycle/min, it remained around 36 torr when the ventilation frequency was progressively increased to 200 cycle/min. The mean peak proximal airway and tracheal pressures were 13 and 12, 11 and 7, and 13 cm H2O (PEEP 2.1 cm H2O) and 7.4 cm H2O (PEEP 3.1 cm H2O) at 30, 100 and 200 cycle/min, respectively. In this open valveless breathing system, desynchronized spontaneous and artificial ventilation occurred quietly without any marked variation in the airway pressures. This preliminary study on a new pneumatic system shows its potential for simplifying and improving infant ventilation.
Chakrabarti
M K
MK
Department of Anaesthetics, Royal Postgraduate Medical School, London, UK.
Whitwam
J G
JG
D000818:Animals; D004867:Equipment Design; D005069:Evaluation Studies as Topic; D006611:High-Frequency Jet Ventilation / Q000295:instrumentation*; D006801:Humans; D007223:Infant; D007442:Intubation, Intratracheal / Q000295:instrumentation*; D008168:Lung / Q000502:physiology*; D008176:Lung Volume Measurements; D011817:Rabbits; D012122:Ventilators, Mechanical