Urinary catheter

definition

A Urinary catheter is a plastic hose that is used in the bladder lies and over which urine can be diverted. This can be done through the urethra (transurethral) or through the Abdominal wall through (suprapubic) into the urinary bladder. Such a urinary catheter can serve both therapeutic (for example in the case of acute urinary retention) and diagnostic purposes.

Catheter assembly

A Urinary catheter consists of a plastic tube that nowadays consists of PVC, latex, polyurethane or silicone is built. The urine is removed through this tube bladder diverted and collected in a vessel.

Depending on the intended use, the catheters also differ in the Shape of the catheter tip, from which the various naming of the catheter is derived, such as "Foley"Or"Nelaton“, the catheter size, the length measured in centimeters, the thickness in “charrière”, and the Additional integrated hoses are added (2-way or 3-way catheter) either for fixing in the bladder or for flushing the same.

Disposable catheter

This transurethral catheter are not designed to last longer in the bladder to linger are accordingly not blockable and usually consist of only one tube. Disposable catheters are the method of choice for emptying the bladder Voiding disorders muscular or neurogenic in nature. Disposable catheters for diagnostic purposes are suitable because of possible minor injuries to the urethra not for use several times a day. They are used to collect urine for laboratory tests or for a single urination acute urinary retention used.

Disposable catheter for the "Intermittent Sterile Disposable Catheterization“ (ISEK), however, are through a very smooth surface with especially lubricious coatings built in such a way that they do not cause any damage to the urethra, which is why they can be introduced into the bladder several times a day to empty them They are used primarily for neurogenic voiding disorders, whereby patients can learn to deal with them themselves.
Sterile gloves are not necessary for this, as the sterile catheter can be inserted directly from the packaging into the urethra using a lubricant. Before doing this, however, the hands and the urethral entrance should be carefully disinfected. The catheter is then pushed through the urethra until urine drains out. There are now also special systems with an integrated collection bag, so that patients are more mobile.

However, the prerequisite for this variant is that the patient is ready to catheterize 4-6 times a day, that there are no urethral constrictions and that the urinary bladder can still hold a volume of at least 400 ml.

To avoid infections, careful disinfection, a sufficient amount of water to drink (at least 1.5 l) and possibly acidification of the urine using lingonberry or cranberry juice.

There are also special ones Disposable catheter for different urological examinations, such as for measuring bladder pressure or installing certain fluids, such as a chemotherapeutic agent Bladder cancer.

Indwelling transurethral catheters

This Catheter shape is used to monitor the fluid balance, for example in the intensive care unit perioperative urine drainage and used after operations to immobilize the bladder and safely drain urine, for constriction of the lower urinary tract or injuries to the urinary tract.
These catheters are mostly called 2-way catheter, often called 3-way catheter created. Via this other tube, a special solution is injected into a bulge in the catheter tip, which fills it up like a balloon and thus prevents the catheter from slipping out of the bladder again. This process is called "Block". The bladder can be flushed through the third tube, if present, for example after an operation on the urinary tract, so that the blood does not clot in the bladder.
Indwelling latex catheters should be left on for less than a week, urinary catheters off silicone however, are suitable for use up to 6 weeks.

The introduction of the catheter is done in a similar way to a single-use catheter under sterile conditions, but a local anesthetic is used in addition to the lubricant.
This catheterization should not be carried out in the case of existing injuries to the urethra with possible Torn urethra, a severe narrowing or existing infections, for example the prostate.

Complications

The catheter system can lead to catheter-induced infections of the urinary tract, which can lead to kidney inflammation and, in the worst case, to sepsis (blood poisoning). In addition, the urethra can be injured, which can lead to bleeding and, in the long-term, scarring of the urethra. In the case of an indwelling catheter, the opening can also become blocked over time, which necessitates a change. After ten years of continuous use of a urinary catheter, squamous cell carcinomas were observed in less than 10 percent.

Suprapubic catheter: In view of the problems that a transurethral catheter can cause, a suprapubic catheter is now often used for long-term urine drainage. With the urinary bladder full, under ultrasound control and local anesthesia, a needle is inserted into the urinary bladder just above the pubic bone and a silicone catheter is inserted at this point, which is then fixed and connected in a sterile manner. However, such a catheter must not be placed if there is a severe tendency to bleed, a proven bladder tumor or a shrinkable bladder; strict indications should also be given in the event of pregnancy.

A dreaded complication is injury to the intestine during puncture, but this only occurs in less than 1% of cases. In addition, infections, slipping of the urinary catheter or bleeding can also occur here.

However, this form of indwelling catheter has the great advantage that it is better tolerated by most patients, especially since the risk of injury and infection is significantly reduced compared to the transurethral route.

Read about this too Urinary tract infection