COMPUTERIZED DETERMINATION OF SPONTANEOUS INSPIRATORY AND EXPIRATORY TIMES IN PREMATURE NEONATES DURING INTERMITTENT POSITIVE PRESSURE VENTILATION .1. A NEW TECHNIQUE

A pneumatic capsule applied to the sub-xiphisternum provides a signal of spontaneous respiratory effort. Purpose-written software analyses t his waveform to determine spontaneous inspiratory and expiratory times . Algorithms reject artefacts. The computerised system allows continuo us measurement of spontaneous inspiratory and expiratory times to be m ade during intermittent positive pressure ventilation. The accuracy of the system was measured in 17 infants ventilated for respiratory dist ress syndrome: median (range) gestation and birth weight were 31 (25-3 8) weeks and 1195 (506-3260) g. The new technique can measure inspirat ory time of individual breaths with a mean error of 5.4% and expirator y time with a mean error of 1.6%.