CANNULA (fr. canule) — the medical tool in the form of a straight line or a curved short tube.
Cannulas, as well as catheters (see), are intended for carrying out diagnostic and to lay down. manipulations in natural superficial perigastriums and the fistular courses. They are produced by hl. obr. from metal. Just as needles, they are supplied with mandrin. There are several types K., used in various areas a wedge, medicine (fig).
In ophthalmology for washing of the lacrimal channel, suction of lenticular weight, and also in an anterior chamber of an eye apply to administration of air and wash liquid cylindrical or flattened To. (fig., 1 — 5).
Various type K. use in otorhinolaryngology (fig., 6 — 13): ear To. to dia. 0,9 and 1,2 mm for suction of blood from a cavity of an outside and middle ear (fig., 6), To. with an olive to dia. 1,6 and 2 mm for bougieurage of a channel of a parotid gland (fig., 7 and 8) and strongly curved To. to dia. 0,8 and 1 mm for bougieurage of a channel of submaxillary gland (fig., 9), To. for blowing off of ears (fig., 11) the bell to dia has on the end. 5 mm, will screw an adapter with an olive in it, on to-ruyu put on a rubber tube; for washing of a maxillary (Highmore's) cavity and an attic use special To. (fig., 12 and 13). At a sialografiya (a X-ray analysis of channels of sialadens) apply set K. to dia. 0,4; 0,6; 0,8 and 1 mm; one of them is shown in the drawing (fig., 10).
To., applied to introduction to a vein of contrast agents, has the conductor entering a gleam of a tube and the speaker on 2 mm from the end of a tube (fig., 14). Such To. it can be used for bougieurage of an umbilical vein and introduction to it of contrast or medicinal agents. For introduction of radioactive granules to a tumor of a brain use a cannula trocar. Unlike usual troakar which core represents an acute stylet, at this To. the end of a core of a trocar is rounded off (fig., 15).
Carry also various nozzles to syringes released by set on five pieces to cannulas: three direct 32, 45 and 50 mm long and two bent — one at an angle 90 °, the second at an angle 120 ° (fig., 16 — 18). They are used at administration of contrast and medicinal agents in outside fistulas of bilious channels, fistulas of a rectum and an anus, and also for washing of various fistulas and wounds.
Special To. are included in the package of an artificial kidney and the cardiopulmonary bypass. From bronchial tubes apply to suction of a secret tracheotomic To. (fig., 19). These are the same tracheotomic tubes, but with a special by-pass branch pipe for a secret.
Exist also so-called transitional To. They allow to use syringe needles with any syringes — Lyuer's syringe and «Record» (fig., 20 and 21).
In animal experiments find application various fiziol. To., produced usually from glass in relation to experimental conditions.
Yu. F. Kabatov.