(From catheterus).

The introduction of the catheter into the bladder; an appellation given by P. AEgineta to this operation, which is required in the following cases.

1. When a stone lies internally on the neck of the bladder, and stops the discharge of the urine.

When a preternatural weakness of the bladder hinders the urine from being discharged in the usual manner; and when other remedies fail, which often happens in women weakened with labour, or when the head of the child presses on the urethra.

3. When, by long retention of urine, the bladder is so. distended and weakened as not to be able to discharge its contents.

4. When mucus, blood, pus, or other matter, sticks in the neck of the bladder, from ulcers, or wounds of the kidneys, or from discharges of bloody urine.

5. When the urethra, or the neck of the bladder, is contracted or obstructed; but in this case bougies are preferred; or when the prostate is scirrhous and prevents the passage of the urine.

6. In the last months of pregnancy it is sometimes useful to introduce the catheter, to draw off the urine, as the weight of the uterus obstructs its discharge.

7. When a prolapsus uteri produces an ischury.

8. When a liquor is to be injected into the bladder; in which case a bladder, or an elastic bottle, may be filled with the liquor to be injected, fastened to the catheter, and, by gentle pressure, conveyed through it.

It is easy to introduce the catheter into the female bladder, since the direction of the urethra is nearly straight; but in males there is some difficulty. Heister directs the man to lie on his back, and the operator to take the penis in his left hand, as he stands on the patient's left side, reclining the penis towards the navel; then he is to introduce the catheter, with its concave part to the belly, into the urethra, so far as the os pubis; and so thrusting it under the symphysis of those bones, and moving the hands gently outwards, forces it into the bladder.

If the catheter is too small, it is the more apt to stop in the corrugations and foldings of the urethra, which often occur in elderly men. Dr. Hunter adds, that some impediments are often met with at the caput gallinaginis, in which case he advises to draw the catheter a little back, and press the end of the catheter a little higher, and then it will slip in; but he cautions against using any force. If a difficulty is still found, he advises the operator to put a finger into the anus, at the same time draw the perinaeum forward, and therewith endeavour to assist the catheter in its introduction.

Mr. Ware, in a paper expressly written on this subject. says, "The mode in which I pass the instrument is as follows: being first thoroughly oiled, I introduce it into the urethra, with its convex part uppermost, and carry it as far as it will pass without using force; then I turn it slowly round, so as to bring its concave side uppermost; and in doing this, I make a large sweep with the handle of the instrument, and at the same time keep my attention fixed steadily on its apex, or inner termination, which I take particular care neither to retract, nor to remove from its first line of direction. When the catheter is turned, it must still be pressed onward, and its handle at the same time gently depressed: by this method it will be made to enter the bladder."

The catheter made use of by Mr. Ware is twelve inches long, which is more than an inch above the ordinary length; and the curvature larger than common, as represented in the plate he has annexed; and with which he has succeeded often, where others of a different size and curvature had failed.

Those catheters are the best that are made with small holes at their ends, instead of long rhomboidal apertures.

In the following cases this instrument cannot be used:

1. When the neck of the bladder is greatly inflamed, for then the urethra is much contracted, and force in this case would endanger a sphacelus. 2. When a caruncle, cicatrix, or hard tubercle, obstructs the passage. 3. In old men, sometimes from the stricture shrinking, or from wrinkles in the urethra. 4. From the distention of the spongy substance of the urethra with blood. 5. From a scirrhosity or preternatural tumour of the prostate gland. 6. From a stone lodged in the neck of the bladder. 7. When the uterus is remarkably prominent and pendulous over the ossa pubis, the neck of the bladder, then forming an angle with the body of the bladder, hinders the passage of the catheter. S. When the uterus is retroverted, in which state it drags the bladder upwards and backwards.