CATHETERS (Greek. katheter the probe) — the tools in the form of tubes intended for introduction to natural channels and cavities of a human body, circulatory and absorbent vessels of medicinal and X-ray contrast means and removal of contents from them with the diagnostic and medical purpose. In some cases catheters can be used as probes, drainages and Bougie. To. are divided into two groups: metal and elastic.
Metal To. are made of brass with protective a covering (usually nickel), or of stainless steel; their surface is processed to high degree of smoothness. Metal To. is more long-lasting, will reliably be sterilized by a thermal or chemical method, however because of rigidity it is difficult to enter them on the twisting or narrowed channels.
Elastic To. make the most numerous group. They are produced from rubber and polyvinyl chloride plastic compound of a special compounding or polyethylene, and also other plastic compounds allowed for use by M3 of the USSR. These materials maintain, as a rule, numerous sterilization by boiling. Sometimes elastic To. spin from silk threads and impregnate with a special varnish.
In addition to odnoprosvetny elastic To., widely use To. dvukhprosvetny which tube is divided by a partition into two channels; each channel comes to an end with a bell for connection of the syringe, for example the intestinal catheter intended for an enteroclysis and other hollow bodies (fig., 3).
For the purpose of giving elastic To. necessary rigidity special wire conductors — mandrins (fig., 4) — a curved two-millimetric wire from stainless steel with the toddler holder who can be fixed in any place of a straight section of a wire core by means of the screw which is available on it are applied.
The catheters applied in otorhinolaryngology
Ear metal To. (fig., 1) for blowing off of an acoustical (eustachian) pipe in Nov one end curved, and another (outside) — executed in the form of a small bell has, diameter to-rogo on 0,5 mm exceeds the size of diameter of a tube To. (2,5 and 3 mm); it is supplied with mandrin.
For bougieurage and blowing off of an acoustical pipe, and also apply a thin catheter No. 4 to administration of medicines (fig., 5). On a surface To. through 10 mm one from another ring risks are caused. In the postoperative period apply to long inhalation of oxygen nasopharyngeal To. (fig., 6) considerable length. They have openings at a spherical end face and eight openings on a cylindrical surface; on the opposite end there is a special adapter which the rubber tube is put on. In need of simultaneous suction of a secret from a nasopharynx apply To. with the adapter having by-pass the branch pipe (fig., 7) connected to the sucking-away device.
For suction of slime from a trachea and bronchial tubes, and also amniotic waters from a throat and a trachea of newborns are issued rubber To. direct and curved (fig., 8 — 10) with a bell and a conical opening under the syringe.
Catheters for blood vessels
To. for exchange hemotransfusion at newborns at incompatibility of blood of mother and the newborn (Rhesus factor conflict) represents the tube from transparent plastic compound pasted in a cannula with a bell (fig., 11). It has on the end oval openings, and a bell of a cannula — a conical opening under a tip of the syringe «Record». This opening can be stoppered, edges is located on a shoot of a bell and attached to it by a thin thong. At distance of 80 and 100 mm from the end To. risks which limit part K are caused two., entered into a vein. To. is issued two numbers (No. 8 and 10 on Sharryera) and has length of 300 mm.
For long intravenous injection of blood and various solutions found application intravenous To. one-time use, having as well a stopper for closing of a bell (fig., 12). These To. are produced three numbers (No. 3, 4 and 5) and are delivered in sterile packaging.
To. for veno-and arteriography represent a tube from X-ray contrast plastic compound; they are led to vessels on the directing conductor from stainless steel. The ends of the conductor are rounded off. Such conductor to dia. 1 (No. 3) and 1,33 mm (No. 4) is flexible and rather elastic, is easily entered into a vessel with the subsequent carrying out on it To. (see. Catheterization of veins puncture , Catheterization of heart ).
The catheters applied in gynecology
Metal ginekol. To. (fig., 2) serves for syringing of a vagina and irrigation of a cavity of the uterus, consists of two tubes connected by the nut having a ridge outer surface. The tube entered into a cavity has oblong openings through which wash liquid arrives. On the opposite end To. there is an olivoobrazny cannula for accession of an elastic hose.
The catheters applied in urology
In urology To. apply to introduction to an urethra, a bladder, ureters and a renal pelvis with to lay down. and the diagnostic purpose (see. Catheterization of uric ways ).
From urethral To. rubber are most common. The simplest is Nelaton's catheter representing a rubber tube of one diameter throughout, length apprx. 250 mm with the rounded-off blind end and one side opening (fig., 13).
In the presence of an obstacle on the course of an urethra (adenoma of a prostate, etc.) it is more preferable to use Timann's catheter having narrowed, dense and klyuvovidno the curved blind end, and on the opposite, expanded in the form of a bell end — a comb (fig., 14). For long drainage of a bladder use bulbous rubber catheters of Pezzer with 2 — 3 roundish openings in a head or Maleko with a head from the rubber crossing strips (fig., 15 — 16). They are entered into a bladder or through an urethra (at women), or through suprapubic vesical fistula (at men) by means of metal mandrin, on Krom To. stretch; at the same time its head stretches in length, decreases in the diameter and To. passes in a bladder. After removal of mandrin a head To. takes the former form and interferes with loss To. from a bladder.
For long drainage of a bladder use rubber To. with Pomerantsev's cylinder — Foul (fig., 17) which has klyuvovidno the curved rounded-off blind end with two openings, and at distance of 20 — 30 mm from it — an inflatable rubber bulb. The cylinder is connected by the additional narrow channel in a wall to a side branch pipe on its outside end. After introduction To. on an urethra in a bladder the cylinder is inflated, entering into it through a side branch pipe a certain amount of liquid. For fixing To. in a bladder it is enough to enter into a cylinder 10 — 15 ml of liquid; for a stop of bleeding from a bed of a prostate after an adenomectomy the cylinder is stretched introduction of 30 — 40 ml of liquid and established To. in the tense state. Similar To. use also for drainage of kidneys (through nefrosty, piyelosty); in this case enter 4 — 6 ml of liquid into a cylinder. For convenience of the subsequent rentgenol, control of correctness of situation K. in a bladder or in a renal pelvis the cylinder can be filled with solution of radiopaque substance (see. Drainage, drainage in urology ). When attempt to carry out through an urethra rubber To. it is not possible, it is necessary to apply elastic and plastic To. They have the narrowed and slightly bent coronoid blind end with side openings and a bell on the outside end — Mercier's catheter (fig., 18). Big density elastic To. allows to lead sometimes him to a bladder when the gleam of an urethra is squeezed from the outside (adenoma, a prostate cancer), but is not narrowed by cicatricial process in a wall of the urethra (stricture). One of types elastic To. the installer — thin is To. with a small club-shaped head (fig., 19), serving for administration (instillation) of medicinal substances in an urethra.
At impossibility to carry out to a bladder rubber and plastic To. use metal K. Muzhska metal To. of 250 mm has dugoobrazno the curved blind end, curvature to-rogo corresponds to a bend of an urethra at men; at distance of 10 — 20 mm from the blind end are available 1 — 2 side a window (fig., 20). Women's metal To. much well men's (150 mm), slightly curved blind end with side openings has (fig., 21). Caliber metal Urals. To. is defined by length of a circle of a tube, in mm (Sharryer's scale). The figure designating number (caliber) To., it is beaten out on its outside end.
Men's urethral To. are issued seven numbers (No. 8, 11, 12, 14, 17, 18, 20), women's — four (No. 8, 11, 14, 17); nurseries metal urethral To. (fig., 22) four numbers (No. 5, 6, 8, I). (After lithotripsy) use the tow truck to removal from a bladder of clots, splinters of a stone — a version men's metal To., but larger sizes with big openings. In order to avoid an injury of a mucous membrane of an urethra edges of openings of the tow truck or splinters of a stone which remained in them enter and take the tow truck with the mandrin filling its gleam.
For orientation metal To. (the directions of his beak) and for convenience of manipulations with it on the outside end To. there are one or two metal rings.
Ureteric catheters have the big length (600 — 700 mm) and small caliber (from No. 3 to 10 on Sharryer's scale); they are done of plastic materials or spun from the silk threads impregnated with a special varnish. On all length ureteric To. are marked by the color strips put through each centimeter: wider strip is applied at distance of 50 mm from its blind end with one side opening (fig., 23), a dual wide strip — on 100 mm, 3 such strips — on 150 mm, 4 — on 200 mm, 1 again — on 250 mm etc. It allows to control depth of introduction To. to an ureter. If ureteric To. it is made of X-ray impenetrable material, he is well visible on survey Urogramum and allows to define the provision of an ureter and the relation to it of shadows, suspicious on a stone. There are options ureteric To., intended for a removing calculus from an ureter by expansion of its gleam below a stone — To. with olivoobrazny expansion on the end, To. with a barrel (Durmashkin's catheter), and also catheters extractors (looplike Tseyssa, korzinchaty Dormia and Pashkovsky).
Sterilization of catheters depends on material, from to-rogo they are made. Metal and rubber To. will sterilize boiling in a distilled water within 30 — 40 min., previously washout by their warm water with soap (hot water is not recommended since leads to coagulation of the remains of blood, pus, slime on To.). Elastic To. will sterilize in disinfecting solution (oxymercuric cyanide 1:1000, Diocidum 1:5000, etc.) within 30 min. Ureteric To. will sterilize vapors of formalin in a special locker, in Krom with openings stack on shelves To., and on a bottom fill paraformaldehyde. For the period of sterilization in a gleam ureteric To. leave thin metal mandrins in order to avoid obstruction of a gleam crystals of paraformaldehyde. After sterilization ureteric To. place in sterile gauze covers which protect them from a touch of fingers and promote aseptic introduction to uric ways. Enter into practice to lay down. institutions elastic To. disposable, undergone sterilization by gamma-rays and released in polyethylene cases.
Yu. F. Kabatov, A. L. Shabad.