Miller D M
Department of Anesthesiology, Tygerberg Hospital, University of Stellenbosch, South Africa.
Anaesthesia. 1992 Jul;47(7):594-6. doi: 10.1111/j.1365-2044.1992.tb02332.x.
A regulator is described for the maintenance of a constant pressure difference above airway pressure during positive pressure ventilation in a cuffed tracheal tube. It comprises a tubular threshold valve which is powered by the anaesthetic gas supply source to a breathing system. The valve is interposed between the anaesthetic gas supply machine and the breathing system creating a pressure differential. The upstream pressure is transmitted to the pilot tube supplying the cuff of a tracheal tube via an upstream connection. The valve is suitable only for breathing systems that require a constant gas supply. The regulator was evaluated during anaesthesia, using a modified Mallinkrodt Hi-Lo jet ventilation tube to obtain simultaneous pressure measurements within the cuff and the lumen of the tracheal tube. A greater pressure was demonstrated in the cuff than in the airway and the two traces were approximately parallel throughout the respiratory cycle. The device should prevent excessive cuff inflation pressure and solves the problem of forgetting to let the cuff down before extubation.
描述了一种用于在带套囊气管导管进行正压通气期间维持高于气道压力的恒定压差的调节器。它包括一个管状阈值阀，该阀由麻醉气体供应源向呼吸系统提供动力。该阀置于麻醉气体供应机和呼吸系统之间，产生压差。上游压力通过上游连接传递到供应气管导管套囊的先导管。该调节器仅适用于需要恒定气体供应的呼吸系统。在麻醉期间对该调节器进行了评估，使用改良的 Mallinkrodt Hi-Lo 喷射通气管在套囊和气管导管管腔内同时进行压力测量。结果表明套囊内的压力高于气道压力，并且在整个呼吸周期中两条曲线大致平行。该装置应能防止套囊过度充气压力，并解决拔管前忘记放气的问题。
