| 摘要 |
1,182,436. Tracheal catheters. V. N. F. LOMHOLT. 12 June, 1967 [16 June, 1966], No. 27021/67. Headings A5R and A5T. A catheter for introducing air into the lungs of a patient and comprising a tube 1 having a sealing bladder 5 to be inflated through a separate duct 6, is provided with a valve 8 which controls gas flow to the bladder 5 in dependance on the pressure of the respiratory gas in the tube 1. The catheter may be inserted into the trachea through the mouth or nose or by tracheotomy and, as shown, the valve 8 comprises a flexible wall which is moved so as to close the gas supply tube 7, 9 when the respiratory gas pressure, which is supplied as positive pressure pulses, in the inlet 4 is at a maximum. With the valve 8 closed the respiratory gas pressure which is in the lungs is said to act on the outside of the bladder 5 so as to increase its seal against the trachea wall. With the respiratory gas at a pressure less than maximum the seal between the bladder 5 and the trachea wall is momentarily broken so that phlegm &c is ejected. |
