Indwelling catheterisation in adults – Urethral and suprapubic (2024)

7. CATHETER COMPLICATIONS

7.1 Catheter-associated urinary tract infection (CAUTI)

The urinary tract is the most common source of nosocomial infection, particularly when the bladder is catheterised [14, 129], accounting for nearly 40% of all hospital-acquired infections [18, 130-133], with the duration of catheterisation being a significant risk factor. [130, 132-135]. Other risk factors are female sex and neurological issues such as paraplegia. [136, 137] The risk of CAUTI can be reduced with greater access to nurses with specialist knowledge, skills and experience in catheter care, and infection avoidance. [138]

CAUTI is present when patients have: (1) had an indwelling urinary catheter for > 2 days, with day 1 being the day of catheter insertion; (2) one sign or symptom including fever, suprapubic tenderness, costovertebral angle tenderness, urinary frequency or urgency or dysuria; and (3) urine culture with > 105 CFU/ml of one bacterial species.

It is estimated that 69% of CAUTI events are avoidable by following guidelines. [136]

It is accepted that bacterial colonisation with catheterisation is inevitable, with some reports estimating the risk of asymptomatic bacteriuria to be around 5% per day, with almost 100% colonisation risk at 7–10 days of catheterisation. Bacteriuria is therefore an almost universal feature of urinalysis and does not require therapy in asymptomatic individuals. [13, 14]

A large cohort study estimated that 12% of patients who have a catheter inserted for 30 days will develop a CAUTI. [136]

Prolonged urinary catheterisation is common among people in long-term care and this carries a high risk of developing CAUTI and associated problems. [43, 137, 139]

Suprapubic catheters are less prone to cause symptomatic infection compared to urethral catheters and are preferable in appropriate patients. [49]

Urinary drainage systems are often reservoirs for multidrug-resistant bacteria, a source of transmission to other patients, and the main risk factor for nosocomial UTI, because they allow microorganisms to bypass host defences and reach the bladder. Extra-luminal contamination may occur when the catheter is inserted, or later by microorganisms ascending from the perineum. Intra-luminal contamination occurs by reflux, which is prevented when closed urinary systems are used. [18, 55, 140]

Antibiotic prophylaxis when changing catheters should only be used for patients with a history of CAUTI following catheter change. There is limited evidence that receiving prophylactic antibiotics reduced the rate of bacteriuria and other signs of infection, such as pyuria, febrile morbidity and gram‐negative isolates in patients’ urine, in surgical patients who undergo bladder drainage for at least 24 hours post-operatively.

There was also limited evidence that prophylactic antibiotics reduced bacteriuria in non‐surgical patients. [141]

The following have been shown to reduce the risk of CAUTI:

There is now good evidence that the following do not reduce the risk of developing CAUTI and therefore such practices are not recommended but may be utilised according to local policy and protocol:

Infection may also occur at the site of suprapubic catheter insertion which may present as cellulitis, requiring oral or intravenous antimicrobial pharmacotherapy depending upon severity, or a subcutaneous abscess requiring formal incision and drainage. Such infections are more common in patients who are immunocompromised.

Prevention

The best way to prevent CAUTI is to remove the catheter as soon as possible and to use alternative methods of bladder drainage, see Section 4.1.

Treatment

Only patients with symptoms and a positive urine culture should receive treatment for CAUTI. [154]

A urine specimen for culture should be obtained prior to initiating antimicrobial therapy for presumed CAUTI due to the wide spectrum of potential infecting organisms and the increased likelihood of antimicrobial resistance. The urine culture should be obtained from the freshly placed catheter prior to the initiation of antimicrobial therapy. [39] If an indwelling catheter has been in place for two weeks at the onset of CAUTI and is still indicated, the catheter should be replaced to hasten resolution of symptoms and to reduce the risk of subsequent catheter-associated bacteriuria and CAUTI. If use of the catheter can be discontinued, a culture of a voided mid-stream urine specimen should be obtained prior to the initiation of antimicrobial therapy to help guide treatment. [39] Long-term indwelling catheters should not be changed routinely. Follow appropriate practices for catheter insertion and care. [39]

7.2 Epididymitis

Epididymitis is inflammation of the epididymis. The condition causes pain and swelling and is almost always unilateral and acute in onset. In older patients, epididymitis is usually due to common urinary pathogens. [14] Epididymitis as a complication of urethral catheterisation is seen significantly more often in patients with indwelling compared to intermittent catheterisation. One study observed epididymitis in almost 5% of spinal cord injury patients with long-term indwelling catheters. The author of the study points out that patient-related factors such as personal hygiene, fluid intake and catheter care should be remembered.[155] (LE: 2a)

7.3 Prostatitis

Prostatitis is a common diagnosis and can be induced with manipulation of the lower urinary tract, such as urethral catheterisation. However, acute bacterial prostatitis is a rare condition and comprises only 5% of all prostatitis. The aetiology of acute bacterial prostatitis includes ascending urethral infection and intraprostatic reflux. Risk factors for the development of acute bacterial prostatitis include unprotected sexual intercourse, phimosis, indwelling urethral catheters, and urinary tract instrumentation; all of which can provide a source for ascending infection. [156] Urethral catheterisation also increases the risk of developing chronic prostatitis. In patients with prostatitis, use of suprapubic catheters can reduce this risk and reduce discomfort compared to urethral catheterisation. [14, 156]

7.4 Catheter blockage

People requiring long-term bladder drainage with an indwelling catheter can experience catheter blockage. The most common problem of long-term indwelling catheters is the formation of encrustations on the luminal and outer surfaces, with consequent blockage and bypassing of urine resulting in urinary leakage. [157]

Around 40–50% of patients with indwelling catheters experience problems with lumen blockage [154, 158-160] (LE: 2b) because of debris or encrustation, due to kinks in a tube or adhesion of catheter to bladder wall.

Catheter encrustation

Encrustation is a result of bacteria in the urine, most commonly Proteus mirabilis, that produce an enzyme called urease, which splits urinary urea into ammonia and carbon dioxide. This results in an increase in alkalinity, providing ideal conditions for the development of crystals; e.g. magnesium ammonium phosphate (struvite) or calcium phosphate. The crystals develop around the eyelets, balloon and internal lumen of the catheter. [157] About 50% of long-term catheterised patients develop encrustations. [161, 162]

Debris

Debris are accumulated tiny pieces of biological matter that originates from urothelial cells from the bladder or tumours shedding cells, blood from infection, disease, urological surgery or trauma, or from mucus.

Biofilm

A thin layer of microorganisms adhering to the surface of a structure, which may be organic or inorganic, together with the polymers that they secrete. [163-165]

Over 70% of blocked catheters are encrusted, and of these, > 60% are associated with bladder stones. [159, 166, 167] The time it takes for catheters to block can vary from 2 to 98 days. [13]

Therefore, it is important to diagnose the exact reason for the blockage to decide the correct course of treatment. Understanding the causes of blockage, and awareness of appropriate management may reduce frequency of blockage and reduce unnecessary washouts that interrupt the closed urinary drainage system.

Prevention and treatment

The evidence base for prevention of catheter blockage is weak with some studies suggesting that potassium citrate supplementation, increased fluid intake and lemon juice supplements all reduce the incidence and severity of catheter encrustation [168] (LE: 2a) Wilde has tested the effect of an educational intervention focusing on optimal fluid intake to decrease blockage, and found that educating the patient resulted in lower frequency of catheter blockage. [169] A Cochrane review based on different washout methods compared saline versus acidic solutions and found no high-level evidence studies on prevention. [157] (LE: 1a)

Bladder washout and instillation seem to be more frequent in clinical practice than other solutions are, despite limited evidence of their effectiveness and concern that washout can damage the bladder mucosa and increase infection due to opening the closed catheter system. [101, 157] (See Chapter 8: Bladder washout)

Further studies have shown that intermittent drainage every 2–4 hours reduces the rate of catheter blockage compared to continuous flow. [58] (LE: 2b)

A dependent-free draining catheter bag may exert significant syphoning pressure, resulting in severe catheter reaction within the bladder urothelium. This polypoidal inflammation in turn may block the catheter holes and result in blockage. (LE: 4) Elevation of the catheter bag to eliminate such pressure may alleviate this risk.

Larger catheter lumina also reduce blockage. Silicone catheters appear to be affected by blockage less often than other catheters, which may be explained by the larger lumen, but the material may also be a contributing factor. [39, 154, 159] (LE: 3)

For Bladder washout – procedure and troubleshooting, see Appendix O

7.5 Catheter bypassing

Catheter bypassing (sometimes called peri-catheter leakage), occurs in 40–67% of patients with indwelling catheters [160, 162], and may have several causes including catheter blockage (see Section 7.4 above), bladder spasm (see Section 7.8 below), constipation, pulling on the catheter, or a too large catheter diameter. Catheter bypassing is not a diagnosis but rather a symptom, and treatment should be aimed at the underlying cause.

7.6 Iatrogenic trauma in indwelling catheterisation

Iatrogenic trauma during urethral catheterisation may, besides causing pain, result in either the formation of a false passage, usually at the level of the prostate or bladder neck, urethral stricture, or traumatic cleaving in men [170, 171] and sphincteric disruption in women. (LE: 3) Such trauma prompting an intervention, accounts for as great a proportion (0.5%) as did symptomatic UTI (0.3%). [172, 173] Iatrogenic trauma can be decreased by medical and nursing personnel education by up to 78%. [174] (LE: 3)

Traumatic cleaving and sphincteric disruption can be avoided by preventing catheter traction [175] or preferably conversion to suprapubic catheterisation. (LE: 4) Paraphimosis may occur when an uncircumcised man is catheterised and the prepuce is not replaced. Care and continued patient and carer education will reduce the incidence of such a complication. (LE: 4)

Eleven percent of urethral strictures requiring urethroplasty arise following urethral catheterisation. [176] (LE: 3)

Suprapubic catheterisation has the potential to cause visceral injury, which although difficult to reliably quantify due to under-reporting, is in the region of 2.5% risk of bowel injury with a 30-day mortality rate of around 1.3% [177-179] (LE: 3) A meta-analysis (Hall et al, 2019) showed a bowel injury rate of 0.7% (11/1490). [180] Visceral trauma is more common among patients with previous lower abdominal surgery and in those with neurological disease. [177] (LE: 3)

Prevention

The incidence of visceral trauma during suprapubic catheter insertion may be reduced by the use of ultrasound to ensure an unhindered route from the skin into the bladder. With training it is possible to detect bowel interposed in the intended path of insertion. (LE: 4) Trauma is also prevented by promoting adequate hydration prior to catheter change, ensuring that there is adequate urine (300 ml) in the bladder. If in doubt, check with bladder scan. If there is insufficient urine in the bladder, try to enlarge the volume in the bladder with saline 0.9% via the transurethral or oral route. [181] (LE: 3)

7.7 Urinary extravasation

Extravasation of urine refers to the condition where an interruption of the urethra or injury of the bladder leads to a collection of urine in other cavities. Injury of the urethra leads to extravasation of urine into the scrotum or penis in males.

Bladder rupture with resultant urinary extravasation can be caused when catheterising with the aid of a catheter introducer although it is almost exclusively related to suprapubic catheter. (LE4)

If the extravasation is intraperitoneal, i.e., the bladder perforation is in a location that causes urine leakage into the peritoneal cavity -- this happens when the injury is in the dome, then laparotomy and primary bladder repair is necessary.

If the leakage is extraperitoneal, i.e., in the pelvic cavity surrounding the bladder but outside the peritoneum, maintaining a urinary catheter that is draining well and insertion of a pelvic drain is sufficient.

7.8 Bladder spasm

Bladder spasm is common in patients with indwelling catheters and is best managed with anticholinergic medication that may be given orally, transdermally or intravesically. Bladder spasms can be related to CAUTI and chronic constipation. Maintaining regular bowel function with a high-fibre and high-fluid intake helps prevent constipation. [124, 125, 162] Sometimes a different catheter (smaller lumen and balloon size) can reduce the spasm caused by constipation. (LE: 4)

Should this fail, intradetrusor injections of botulinum toxin A may be administered. [182] (LE: 3)

7.9 Bladder pain

Bladder pain is experienced in about 25% of patients [185] and may be an extreme form of urgency as a consequence of detrusor spasm, or may be a distinct entity without an associated urge to void.

Catheter-associated bladder pain is exacerbated by constipation, which therefore should be treated as a priority in affected individuals. [186] (LE: 3). Catheter-associated bladder pain is mentioned here as a possible complication of catheterisation. Other aspects of bladder pain and painful bladder syndrome fall outside the remit of these guidelines.

7.10 Haematuria

Haematuria may occur following catheterisation and is usually self-limiting. During urethral catheterisation, prostatic trauma may be the underlying cause, although decompression of high-pressure chronic retention may also result in haematuria.

If such haematuria fails to settle, irrigation through a 3-way catheter may be required or in more severe cases, formal bladder washout under general anaesthesia may be necessary. (LE: 4)

Haematuria following suprapubic catheterisation may be resolved by irrigation through the catheter or via an additional, urethral catheter. (LE: 4)

The frequency of gross haematuria is significantly higher with a longer duration of catheterisation and is seen in about 40% of patients. [188] In neuro-urological patients, gross haematuria was one of the presenting symptoms in 31.6% of patients diagnosed with squamous cell carcinoma of the bladder. [189]

7.11 Granuloma formation

This complication is limited to suprapubic catheterisation and merely requires application of silver nitrate in most cases. Rarely, if this is ineffective, surgical excision of the granuloma may be required with or without re-siting the catheter. (LE: 4)

7.12 Inability to remove catheter

Catheters may occasionally prove impossible to remove via balloon deflation. This may be as a consequence of balloon calcific encrustation or a faulty deflation mechanism.

Cutting the catheter below the bifurcation may result in deflation and allow catheter removal but if this fails, ultrasound-guided transabdominal balloon puncture may be required. (LE: 4)

Please be aware that cutting the catheter will invalidate product liability.

An alternative method in the event of being unable to remove a suprapubic catheter is to utilise a flexible cystoscope and attempt balloon perforation with a metal guide wire of fine-gauge needle. Evacuation of all catheter matter is essential. (LE: 4)

Transrectal perforation of catheter balloons should be avoided because of the risk of sepsis. (LE: 4) Formation of a catheter knot in the bladder is a rare cause of catheter retention, and usually requires endoscopic removal. [190]

7.13 Squamous cell carcinoma

Long-term catheterisation, in common with other forms of long-term urothelial irritation, may increase the risk of squamous cell carcinoma formation.

Long-term catheterisation in patients with spinal cord injury is the greatest predisposing factor for the development of non-schistosomiasis-induced squamous cell carcinoma of the bladder. [191] The only potential way of reducing this risk is to promote intermittent catheterisation as first choice for patients with neuro-urological disease. [189] (LE: 3)