Urinary catheterisation

In urinary catheterization a latex, polyurethane, or silicone tube known as a urinary catheter is inserted into a patient's bladder via the urethra. Catheterization allows the patient's urine to drain freely from the bladder for collection. It may be used to inject liquids used for treatment or diagnosis of bladder conditions. A clinician, often a nurse, usually performs the procedure, but self-catheterization is also possible. The catheter may be a permanent one (indwelling catheter), or an intermittent catheter removed after each catheterization.Foley catheterCondom catheterMale Self-CatheterizationFemale Self-CatheterizationHow to properly drain a condom catheter.How to properly drain a Foley catheter.Illustration of a closed urinary drainage method.Illustration of how to empty a urinary drainage bag. In urinary catheterization a latex, polyurethane, or silicone tube known as a urinary catheter is inserted into a patient's bladder via the urethra. Catheterization allows the patient's urine to drain freely from the bladder for collection. It may be used to inject liquids used for treatment or diagnosis of bladder conditions. A clinician, often a nurse, usually performs the procedure, but self-catheterization is also possible. The catheter may be a permanent one (indwelling catheter), or an intermittent catheter removed after each catheterization. Catheters come in several basic designs: Catheter diameters are sized by the French catheter scale (F). The most common sizes are 10 F (3.3mm) to 28 F (9.3mm). The clinician selects a size large enough to allow free flow of urine, and large enough to control leakage of urine around the catheter. A larger size is necessary when the urine is thick, bloody, or contains large amounts of sediment. Larger catheters, however, are more likely to damage the urethra. Some people develop allergies or sensitivities to latex after long-term latex catheter use making it necessary to use silicone or Teflon types. Evidence does not support an important decrease in the risk of urinary tract infections when silver-alloy catheters are used. In males, the catheter tube is inserted into the urinary tract through the penis. A condom-type catheter (also known as a 'Texas catheter'), if used, fits around the tip of the penis, rather than being inserted. In females, the catheter is inserted into the urethral meatus, after a cleansing using povidone-iodine or Dakin solution. 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 would rely on anatomical landmarks and patience when dealing with such a patient. In the UK it is generally accepted that cleaning the area surrounding the urethral meatus with 0.9% sodium chloride solution is sufficient for both male and female patients as there is no reliable evidence to suggest that the use of antiseptic agents reduces the risk of urinary tract infection. Males may have a slightly higher incidence of bladder spasms. If bladder spasms occur, or there is no urine in the drainage bag, the catheter may be blocked by blood, thick sediment, or a kink in the catheter or drainage tubing. Sometimes spasms are caused by the catheter irritating the bladder, prostate, or penis. Such spasms can be controlled with medication such as butylscopolamine, although most patients eventually adjust to the irritation and the spasms go away. Common indications to catheterize a patient include acute or chronic urinary retention (which can damage the kidneys), orthopaedic procedures that may limit a patient's movement, the need for accurate monitoring of input and output (such as in an ICU), benign prostatic hyperplasia, incontinence, and the effects of various surgical interventions involving the bladder and prostate. For some patients, the insertion and removal of a catheter may cause excruciating pain, so a topical anaesthetic is used. Catheterization would be performed as a sterile medical procedure by trained, qualified personnel, using equipment designed for this purpose, except in the case of intermittent self-catheterization where patients have been trained to perform the procedure themselves. Intermittent self-catheterization is performed by the patient four to six times a day, using a clean technique in most cases. Nurses use a sterile technique to perform intermittent catheterization in hospital settings. Incorrect technique may cause trauma to the urethra or prostate (male), urinary tract infection, or a paraphimosis in the uncircumcised male. For patients with spinal cord lesions and neurogenic bladder dysfunction, intermittent catheterisation (IC) is a standard method for bladder emptying. The technique is safe and effective and results in improved kidney and upper urinary tract status, lessening of vesicoureteral reflux and amelioration of continence. In addition to the clinical benefits, patient quality of life is enhanced by the increased independence and security offered by self-catheterization.