From Big Medical Encyclopedia

COUGH ARTIFICIAL — artificial reproduction of tussive pushes by the short-term message of pneumatic ways of lungs with a capacity, pressure in a cut is lower, than in lungs. The difference of pressure creates high speed of the air flow in bronchial tubes which is carrying away towards a trachea a phlegm and other particles from respiratory tracts including from those their sites into which it is impossible to enter a catheter for suction of exudate.

Fig. 1. Roentgenograms of the left lung: 1 — bronchial tubes are filled with sulfoiodolipolum during the carrying out a bronchography; 2 — after use of the device «artificial cough» the amount of contrast medium in bronchial tubes significantly decreased
Fig. 2. The device for artificial cough of «IKAR-3».

To. and. apply when the natural tussive reflex or when is lost in whole or in part To. causes pain, napr, in the postoperative period. At diseases, when the increase in intrathoracic pressure obligatory at natural cough (see), it is undesirable, To. and. has that advantage that it is not connected with increase in intrathoracic pressure. For To. and. use vacuum capacity, in a cut negative pressure from — 50 to — 400 mm of mercury is supported. For elimination of so-called valve effect (a smykaniye of walls of bronchial tubes at slow pressure decrease in their gleam) artificial tussive pushes with the high instantaneous velocity of a flow of air use. At such speed of a wall of bronchial tubes during falling of intra bronchial pressure do not manage to be closed. It is reached by use for the message of respiratory tracts with a vacuum capacity of the high-speed managed valve or a zolotnik (crane), the section through passage to-rogo opens completely for a small time term (usually for 0,05 — 0,1 sec.). Speed of valve crack is the key parameter defining efficiency of a tussive push. As a rule, carry out several artificial tussive pushes at which particles of a phlegm rise in the bronchial tubes available to its suction by means of a catheter. The procedure repeats several times. Drainage effect of the procedure K. and. after filling of bronchial tubes with a contrast agent clearly it is visible on roentgenograms (fig. 1).

For carrying out To. and. various models of special devices are applied. One of such models — the domestic device IKAR-3 is presented in fig. 2. This device is intended for To. and. and suctions of bronchial contents. Vacuum is created by means of the ejector put in action by compressed gas (air or oxygen). The device can be used both at independent breath of the patient, and during artificial ventilation of the lungs and an anesthesia.

Bibliography: Zilber A. P. Artificial ventilation of the lungs at acute respiratory insufficiency, M., 1978; Sykes M. K., Mac Nicol M. U. and Campbell E. D. M. Respiratory insufficiency, the lane with English, M., 1974.

S. A. Glukhov.