A pressure curve monitor for intratracheal jet ventilation

Abstract Most of the complications during intratracheal jet ventilation for laryngomicroscopy are due to the unnoticed wearing off of laryngeal muscle relaxation. Recovering laryngeal muscle function will, by slightly narrowing the size of the glottis, influence the slope of the quickly rising part of the pressure curve, when influences on maximum airway pressure are still not detectable. An electronic device incorporating the window comparator technique monitors the pressure curve and sets off an alarm before changes in maximum airway pressure or recovery of muscle strength in the forearm are detectable. The pressure curve monitor could be useful also with intratracheal jet ventilation for treating adult respiratory deficiency and with conventional ventilators during anaesthesia to detect the wearing off of muscle relaxation.