Thursday 18 November 2010

TWOC

Procedure to undertake a trial without catheter

An indwelling urinary catheter is a commonly used medical device but its use is associated with complications

An indwelling urinary catheter is a commonly used medical device but its use is associated with complications (DH, 2005; 2003). Any patient with a catheter should be reviewed regularly (NICE, 2003) and a planned trial without catheter (TWOC) should take place when an assessment indicates that it can be removed.

Wareing (2001) describes a TWOC or voiding trial as a common procedure carried out in many clinical settings. The purpose of the trial is to assess patients’ ability to empty their bladder successfully following the removal of their indwelling urinary catheter.

A clinical procedure should be followed in order to achieve optimum outcomes and to ensure that patient safety is maintained. A TWOC may fail and practitioners must be able to monitor and assess their patients for complications and manage these if they occur.

Rationale for a TWOC

To reduce the risk of catheter-associated complications

Indwelling urinary catheters are widely used in clinical practice for a variety of reasons and may be short to medium term (7-28 days) or long term ((gt)28days), depending on the rationale for catheterisation (Box 1). Urinary tract infections account for 23% of all healthcare-associated infections (Emmerson et al, 1996) and 80% of these are related to urinary catheters (DH, 2003). The risk of infection increases the longer the catheter is in place (DH, 2005). It is therefore necessary to remove a catheter as soon as possible because timely removal reduces the risk of complications.

Other complications include pain, tissue trauma, bleeding, inflammation, stricture formation, meatal and bladder neck erosion, and altered body image (Getliffe, 2003).

To end an episode of careA catheter may be inserted following clinical or surgical procedures and removed within a predetermined timeframe, for example following major surgery. An indwelling catheter is sometimes inserted to facilitate the healing of wounds or skin excoriation if these are caused or exacerbated by urinary incontinence. Once healing is complete, the catheter should be removed.To review the outcome of treatment A TWOC may be performed to assess whether a patient’s urinary problems have improved or need further management. A voiding problem may have been spontaneously resolved or medical treatment may have been successful. For example, alpha-blocking drugs such as tamsulosin hydrochloride may have been prescribed to relax the smooth muscle of the prostate. Prostatic enlargement is the most common cause of an outflow obstruction in men (Manikandan et al, 2004) and alpha-blocking drugs can help men with prostate enlargement to void following an episode of urinary retention (Lucas et al, 2005).Current practice

Recent guidelines (NICE, 2003; DH, 2005; 2003) have suggested that urinary catheters often remain in place for longer than necessary, particularly in continuing care settings. It is therefore important that the rationale for catheterisation should be documented as well as the anticipated date for a TWOC.

A recent US study demonstrated that using reminders in patient records to review the need for a catheter reduced the time that the patient was catheterised (Saint, 2005).

The procedure

When to remove a catheter

A TWOC should take place as soon as possible following catheter insertion or when a reassessment of the patient indicates that it is safe to do so (NHS Quality Improvement Scotland, 2004). There is a lack of consensus about the best time of day to remove a catheter but research involving urology patients suggests midnight (Kelleher, 2001).

A positive TWOC outcome occurred in Kelleher’s (2001) study, the bladder filled overnight while the patient was sleeping, increasing the volume of the first void in the morning.

Other practitioners suggest that early morning, for example 6am, is a suitable time, particularly if the procedure is taking place in an outpatient clinic (Addison, 2001) or in the patient’s own home (Wareing, 2001; Warrilow et al, 2004). This ensures that the patient receives full support and monitoring during the day and that the voided urine can be measured the same day (Addison, 2001). It also reduces the risk of disrupted sleep and the patient is awake and alert and more able to challenge their bladder with a regular fluid intake and voiding activity.

Where the procedure should take place Dedicated TWOC clinics are run in hospitals (Addison, 2001; Gidlow and Roodhouse, 1998) and the community (Warrilow et al, 2004; Wareing, 2001). The aim of these clinics is to ensure formal management of the procedure and best outcomes for the patient. However a TWOC procedure can be undertaken in any clinical setting if the healthcare practitioner has the appropriate knowledge and skills. Access to monitoring equipment is important to assess the outcomes of the trial. If the catheter is removed in the patient’s home, the health professional should provide contact numbers in case problems occur and visits must be planned with the patient to evaluate the trial (Addison, 2001; Wareing, 2001).

Patient education

Patients must be made aware of what the procedure involves and what to expect. Education can assist in a successful outcome and reduce levels of anxiety (Abbott, 1998). Some patients may take responsibility for recording their fluid intake, measuring their own urine output and documenting this (Addison, 2001; Wareing, 2001). They also need to understand the importance of a regular fluid intake during their TWOC and should be encouraged to consume approximately 1.5-2L a day so that enough urine is produced to challenge their bladder.

Patients must understand the importance of reporting discomfort immediately, particularly if it is associated with problems passing urine (Addison, 2001). They should be instructed not to drink if this occurs, until they have been reassessed by a healthcare practitioner (Addison, 2001); this is particularly important if the TWOC is taking place in the patient’s home. Patients should also be told that they may experience discomfort the first time they pass urine, and informed that the urine may be bloodstained as a result of trauma following the removal of the catheter (Wareing, 2001).

Methods of monitoring and evaluation

Fluid balance charting Fluid intake and output must be accurately recorded. The output should be approximately equal to intake and voided volumes should be consistently greater than 100ml (Wareing, 2001).

Bladder scanning It is considered best practice to use a portal bladder ultrasound scanner to assess for a residual volume of urine in the bladder during the procedure (Addison, 2001). The healthcare practitioner must be competent to use the scanning equipment (Addison, 2000) and be able to interpret the results (Addison, 2001).

Catheterisation Catheterising with a nelaton (intermittent) catheter to determine the amount of residual urine can be undertaken if no scanning equipment is available. It may be indicated if the patient appears to be retaining urine in the bladder and significant residual volumes are suspected ((gt)300ml) (Addison, 2001).

Practitioners must be familiar with the signs and symptoms of urinary retention. These can include: a palpable bladder which is dull on percussion, discomfort, pain, a desire to void with an inability to pass enough urine to satisfy the desire and poor urine output (Bickley and Hoekelman, 2003; Addison, 2001).

Outcomes

The TWOC may be considered successful if the patient is able to empty the bladder without significant residual urine occurring ((lt)300ml) (Addison, 2001). Patients may need several trials before achieving a positive outcome, particularly after urological surgery (Lucas et al, 2005) or a prolonged period of catheterisation (Getliffe, 2003). Loss of bladder function is likely if a catheter valve has not been used during long-term catheterisation (Addison, 1999). A catheter valve allows urine to be retained in the bladder and it is then released intermittently, allowing the bladder to retain its tone.

Other factors associated with failure of a TWOC include:

- The patient being older than 75 years;

- A volume greater than 1,000ml drained when the patient was first catheterised (Hamm and Speakman, 2002);

- A large prostate gland before resection (Kumar et al, 2000).

- Constipation.

These factors should be considered by practitioners when they carry out a TWOC.

Complications

Ultimately the outcome of the TWOC determines how the patient is managed (Wareing, 2003). Local policy and protocol should be followed regarding care pathways if complications occur and the TWOC fails. Other than failure to void successfully, other negative outcomes for the patient can include problems such as incontinence and urgency and frequency.

Incontinence Pelvic floor exercises may help to resolve incontinence related to urological surgery, particularly following a transurethral resection of prostate gland (TURP) (Heath and Watson, 2003). Intractable incontinence may recur if this was the rationale for catheterisation. This may be managed better in other ways, such as body-worn absorbent pads, but recatheterisation may be indicated.

Urgency and frequency of micturition Urgency and frequency may be due to urinary tract infection and require antibiotic therapy. It may also occur following long-term catheterisation, particularly if a catheter valve was not used to help maintain bladder tone (Addison, 1999). The bladder may only be able to accommodate small volumes of urine and the patient may need to empty their bladder frequently as a result.

Urgency and frequency may also be a symptom associated with poor bladder emptying and the presence of residual urine volumes in the bladder. Patients may explain that their bladder ‘never feels empty’ and so they need to void more frequently (White and Getliffe, 2003). Anticholinergic medication such as oxybutinin may help to relieve symptoms of frequency and urgency not related to infection or the presence of a residual volume of urine. Bladder retraining to increase the intervals between voiding and therefore the bladder capacity may be helpful (Dolman, 2003).

Incomplete bladder emptying/inability to void completely. If the patient is unable to void successfully, an ongoing plan of care must be discussed and agreed with them. An indwelling catheter may need to be reinserted but this depends on the patient’s views, severity of incontinence or voiding success. If a catheter is reinserted, a repeat TWOC should be discussed and arranged with the patient.

Intermittent self-catheterisation (ISC) should also be discussed with the patient. Research shows that ISC may resolve bladder-emptying problems and some patients resume normal voiding activity as a result of this treatment (Naish, 2003).

Conclusion

A TWOC is an important and integral part of indwelling urinary catheter management. The procedure should be planned and must take place to avoid the risk of complications caused by indwelling urinary catheters. Local policy, procedure and care pathways should be followed where these are available.

This article has been double-blind peer-reviewed.