Urinary catheterization

In urinary catheterization, a urinary catheter (such as a Foley catheter) is a plastic tube which is either inserted through a patient's urinary tract into their bladder or attached to a male patient's penis. A balloon located at the end of the catheter is usually inflated with sterile water to prevent the catheter from slipping out. In this manner, the patient's urine is collected and contained for various medical purposes. The procedure of catheterization will usually be done by a clinician, often a nurse, although self-catheterization is possible as well.

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Types of catheterization

  Catheters come in a large variety of sizes; materials (latex, silicone, PVC, or Teflon); and types (Foley catheter, straight catheter, or coude tip catheter). In the case of internal catheters, those inserted into the urethra, the smallest size is usually recommended, although a larger size is sometimes needed to control leakage of urine around the catheter. A large size can also become necessary when the urine is thick, bloody or contains large amounts of sediment. Larger internal catheters, however, are more likely to cause damage to the urethra. Some people have developed allergies or sensitivities to latex after long-term latex catheter use. In such cases, silicone or Teflon types should be used.

Proper catheter use can also often be determined by the length of time for which the process is necessary: long-term (often called indwelling) or short-term use:

Short-term use

In some situations, incontinent patients are catheterized to reduce their cost of care. A condom catheter, which fits on the outside of the penis using adhesive, can be used for short-term cathaterization in males. However, long-term catheterization is not recommended because chronic use carries a significant risk of urinary tract infection..

Long-term use

A catheter that is left in place for a period of time may be attached to a drainage bag to collect the urine. There are two types of drainage bags: The first is a leg bag, a smaller drainage device that attaches by elastic bands to the leg. A leg bag is usually worn during the day, as it fits discreetly under pants or skirts, and is easily emptied into a toilet. The second type of drainage bag is a larger device called a down drain that may be used during the night. This device is usually hung on the patient's bed or placed on the floor nearby.

During long-term use, the catheter may be left in place during the entire time, or a patient may be instructed on a procedure for placing a catheter just long enough to empty the bladder and then removing it (known as clean intermittent self-catheterization). Patients undergoing major surgery are often catheterized and may remain so for some time.

Long-term catheterization can expose patients to an increased risk of infection. Long-term catheterization as a remedy for incontinence is not appropriate, as the risks outweigh the benefits.

Sex differences

In males, the catheter tube is inserted into the urinary tract through the penis. A condom catheter can also be used. In females, the catheter is inserted into the urethral meatus, after a cleansing using betadine. The procedure can be complicated in females due to varying layouts of the genitalia (due to age, obesity, Female genital cutting, childbirth, or other factors), but a good clinician should rely on anatomical landmarks and patience when dealing with such a patient.

Possible causes and effects

Common indications to catheterize a patient include acute or chronic urinary retention, orthopedic procedures that may limit a patient's movement, the need for accurate monitoring of input and output (such as in an ICU), benign prostatic hypertrophy, incontinence, and the effects of various surgical interventions involving the bladder and prostate.

For many patients the insertion and removal of a catheter can cause severe pain, so a topical anesthetic can be used. Catherization should be performed as a sterile medical procedure and should only be done by trained, qualified personnel, using equipment designed for this purpose.

Complications of catheter use may include: urinary tract or kidney infections, blood infections (sepsis), urethral injury, skin breakdown, bladder stones, and blood in the urine (hematuria). After many years of catheter use, bladder cancer may also develop.

See also

• Foley catheter
• French catheter scale