Management of men with benign prostatic hyperplasia or bladder outflow obstruction

Strong indications for treatment (usually prostatectomy) include:

 1. acute retention (see Chapter 65) in fit men with no other cause for retention (drugs, constipation, recent operation, etc.) (accounts for 25 per cent of prostatectomies);

2. chronic retention and renal impairment: a residual urine of 200 ml or more, a raised blood urea, hydroureter or hydronephrosis demonstrated on urography, and uraemic manifestations (accounts for 15 per cent of prostatectomies);

3.      complications of bladder outflow obstruction: stone, infection and diverticulum formation;

4.  haemorrhage: occasionally, venous bleeding from a ruptured vein overlying the prostate will require prostatectomy to be performed;

5. elective prostatectomy for severe symptoms of ‘prostatism’: this accounts for about 60 per cent of prostatectomies. Increasing difficulty in micturition, with considerable frequency day and night, delay in starting, and a poor stream are the usual symptoms for which prostatectomy is advised. Frequency alone is never an indication for prostatectomy. The natural progression of outflow obstruction is variable and rarely gets worse after 10 years. Severe symptoms, a low maximum flow rate (<10 mI/second) and an increased residual volume of urine (100—250 ml) are relatively strong indications for operative treatment. The exact cut off for operative or nonoperative treatment will depend on careful discussion between patient and urologist.

Acute retention

The management of retention is discussed in detail in Chapter 65. Once the bladder has been drained by means of a catheter, the patient’s fitness for treatment is determined. If retention was not caused by drugs or constipation then pro­statectomy would usually be the correct management. Unfit men or those with dementia may be treated by means of indwelling prostatic stents or a catheter. Similar comments apply to men with chronic retention once renal function has been stabilized by catheterization.

Special problems in the management of chronic retention (see Chapter 65 for general management of retention)

Men who do not have symptoms suggestive of coexistent infection and with good renal function do not necessarily require catheterization before proceeding to prostatectomy on the next available list. For those who are uraemic, urgent catheterization is mandatory to allow renal function to recover and stabilize. Haematuria often occurs following catheterization owing to collapse of the distended bladder and upper tract, but settles within a couple of days.

Uraemic patients with chronic retention are often dehydrated at the time of admission. Owing to the chronic back pressure on the distal tubules within the kidney, there is loss of the ability to reabsorb salts and water. The result, following release of this pressure, may be an enormous outflow of salts and water which is known as postobstructive diuresis. It is for this reason that a careful fluid chart, daily measure­ments of the patient’s weight and serial estimations of creatinine and electrolytes are mandatory. Intravenous fluid replacement is required if the patient is unable to keep up with this fluid loss. These patients are often anaemic and may require a blood transfusion once fluid balance is stabilised (if haemoglobin is <9 g/litre).

Indications for elective treatment in men with symptoms of prostatism

Following careful assessment (see section of assessment of men with prostatism), the following questions should be answered.

1. Is bladder outflow obstruction present?

In many cases, the findings of significant symptoms (assessed by symptoms scoring), a benign prostate supplemented by the finding of a low maximum flow rate [<10—12 ml/second for a good voided volume (>200 ml)] will suffice to make a reasonable working diagnosis of BOO. Some men — particularly those with irritative symptoms, suspected neurological disease or those with technically imperfect flow rate measurements —will require pressure—flow studies to be performed.

2. How severe are the symptoms and what are the risks of doing nothing?

Severe symptoms and a large residual volume of urine will usually require treatment. Men with mild symptoms, good flow rates (>10 mI/second) and good bladder emptying (residual urine <100 ml) may be safely managed by reassurance and review: such patients rarely develop severe complications such as retention in the long term.

3. Is the man fit for operative treatment?

4. What treatments are available, what are the outcomes and do the side effects justify treatment?

In men who do not have a strong indication for operative treatment the options for treatment are shown below

Nonoperative treatment for BPH

 Conservative ‘watchful waiting’ — general advice about fluid intake, use of anticholinergic medication in men with mild symptoms

Use of prostatic stents in men with retention who are unfit or have dementia

Balloon dilatation of the prostate (experimental)

Drug treatment to supplement conservative treatment in men with mild symptoms (a-adrenergic blocking agents and 5a-reductase inhibitors)

Use of permanent indwelling catheters in unfit men with retention or associated dementia

Minimally invasive methods

These are new and their roles are not yet determined:

  contact laser of the prostate;

   microwave treatment of the prostate (thermo therapy);

  other new minimally invasive methods of prostate destruc­tion including microwave hyperthermia and thermal abla­tion and high—energy ultrasound.

Conventional operative treatment

This includes:

      transurethral resection of the prostate (TURP);

  bladder neck incision for the small prostate (<20 g);

  open prostatectomy for the big gland (>—80—100 g).

Men with symptoms attending for elective treatment (excluding acute and chronic retention)

Conservative treatment

It is in men with relatively mild symptoms, reasonable flow rates (>10 ml/second) and good bladder emptying (residual urine <100 ml) that careful discussion over the merits and side effects of operative treatment is warranted. Waiting for a period of 6 months after careful discussion of the diagnosis is indicated. After this a repeat assessment of symptoms, flow rates and ultrasound scan is helpful; many men with stable symptoms will elect to leave matters be. Advice over limiting fluid intake in the evening and careful use of propantheline to help with irritative symptoms is also useful.

Drugs

In men who are very concerned about the development of sexual dysfunction after TURP, the use of drugs may be helpful. Two classes of drugs have been used in the treatment of men with BOO. These include alpha-adrenergic blocking agents which inhibit the contraction of smooth muscle which is found in the prostate. The other class of drug is the 5alpha­reductase inhibitors, which inhibit the conversion of testosterone to DHT, the androgen which is effective. These drugs, when taken for a year, result in a 25 per cent shrinkage of the prostate gland. On average, both drugs seem to be of similar efficacy, and although the 5alpha-reductase inhibitors have fewer side effects, alpha-blockers work more quickly. They result in improvements in maximum flow rates by about 2 ml/second greater than placebo and result in mild (20 per cent) improvement in symptom scores. TURP, however, results in improvements in maximum flow rates from 9 to 18 ml/second and 75 per cent improvements in symptom scores. These drugs are expensive in comparison to their effectiveness and a significant proportion of men who try these drugs will subsequently undergo TURP. Their role may be best targeted on men who have failed an initial trial of watchful waiting and who wish to avoid surgery for a period.

Operative treatment

Apart from the strong indications for operative treatment mentioned above, the commonest reason for TURP is a combination of severe symptoms and a low flow rate <12 ml/second. The key is to assess symptoms carefully and to counsel men about side effects and likely outcome before advising operative treatment.

Counselling men undergoing prostatectomy

Men undergoing prostatectomy need to be advised about the following.

1.  Retrograde ejaculation occurs in about 65 per cent of men after prostatectomy.

2. Erectile impotence occurs in about 5 per cent of men, usually in those whose virility is waning.

3. The success rate — on the whole men with acute and chronic retention do well from the symptomatic point of view. Ninety per cent of men undergoing elective operation for severe symptoms and urodynamically proven BOO do well in terms of symptoms and flow rates. Only about 65 per cent of those with mild symptoms or those with weak bladder contraction as the cause of their symptoms do well. Men with unobstructed detrusor instability do not respond well to TURP. This is the reason for carefully documenting the severity of symptoms and flow rates — supplemented when necessary by pressure—flow studies — before deciding on treatment.

4. The risk of reoperation after TURP is about 15 per cent after 8—10 years.

5.       The morbidity rate: death after TURP is infrequent (<0.5 per cent), severe sepsis is found in about 6 per cent and severe haematuria requiring transfusion >2 units is found in about 3 per cent. After discharge about 15—20 per cent of men subsequently require antibiotic treatment for symptoms of urinary infection. Risk factors for complications include admission with retention, prostate cancer, renal impairment and advanced age.

Methods of performing prostatectomy

The prostate can be approached (1) transurethrally — TURP, (2) retropubically — RPP, (3) through the bladder (transvesical

— TVP) or (4) from the perineum (Fig. 66.12). Preliminary vasectomy is now no longer performed.

Transurethral resection of the prostate

TURP has largely replaced other methods unless diverticulectomy or the removal of large stones necessitates open opera­tion; over 95 per cent of men being treated by trained urologists can be dealt with by TURP. The earlier instruments designed by McCarthy have been replaced by single-hand-operated instruments often being used under video control. Perhaps the greatest advance in the history of transurethral surgery was marked by the development of the rigid lens system of Professor Harold Hopkins. His lenses illuminated by a fibre-optic light source permit unparalleled visualisation of the working field. Men with indwelling catheters, those with recent urinary infection, those with chronic retention or those with prosthetic material or heart valves should receive broad-spectrum prophylactic antibiotics with amoxycillin plus cefuroxime intravenously at induction of anaesthesia.

Strips of tissue are cut from the bladder neck down to the level of the verumontanum (Fig. 66.13). Cutting is performed by a high-frequency diathermy current which is applied across a loop mounted on the hand-held trigger of the resectoscope. Coagulation of bleeding points can be accurately achieved and damage to the external sphincter is avoided provided one uses the verumontanum as a guide to the most distal point of the resection. The ‘chips’ of prostate are then removed from the bladder using an Ellik evacuator. Hypo­natraemia is avoided by using 1.5 per cent isotonic glycine for irrigation and the recent introduction of continuous flow resectoscope makes the procedure swift and safe in experienced hands. At the end of the procedure, careful haemostasis is performed and a three-way, self-retaining catheter irrigated with isotonic saline is introduced into the bladder to prevent any further bleeding from forming blood clots. Irrigation is continued until the outflow is pale pink and the catheter usually removed on the second or third post­operative day. In men with small prostates or bladder neck dyssynergia or stenosis, it is better to divide the bladder neck and prostatic urethra with a diathermy ‘bee-sting’ electrode.

Retro pubic prostatectomy (Millin, 1945)

Using a low, curved transverse suprapubic Pfannenstiel incision, which includes the rectus sheath, the recti are split in the midline and retracted to expose the bladder with its typical appearance of pale brown muscle bundles with a loose covering of fatty tissue and veins. With the patient in the Trendelenberg position, the surgeon separates the bladder and the prostate from the posterior aspect of the pubis. In the space thus obtained the anterior capsule of the prostate is incised with diathermy below the bladder neck, care being taken to obtain complete control of bleeding from divided prostatic veins by suture ligation. The prostatic adenoma is exposed and enucleated with a finger. A wedge is taken out of the posterior lip of the bladder neck to prevent secondary stricture in this region. The exposure of the inside of the prostatic cavity is good, and control of haemorrhage is achieved with diathermy and suture ligation of bleeding points before closure of the capsule over a Foley catheter (inserted per urethram) draining the bladder.

Transvesical prostatectomy

The bladder is opened, and the prostate enucleated by putting a finger into the urethra, pushing forwards towards the pubes to separate the lateral lobes, and then working the finger between the adenoma and the false capsule. In Freyer’s operation (1901) the bladder was left open widely and drained by a suprapubic tube with a 16-mm lumen, in order to allow free drainage of blood and urine. Harris (1934) advocated control of the prostatic arteries by lateral stitches inserted with his boomerang needle, the bladder wall was closed and the wound drained.

Perineal prostatectomy (Young)

This has now been abandoned for the treatment of BPH.

After-treatment

Most urologists irrigate the bladder with sterile saline by means of a three-way Foley catheter for 24 hours or so.

Complications

Local

Haemorrhage is a major risk following prostatectomy whatever the surgical approach. Care should be taken in diathermising arterial bleeding points after TURP; they are often better seen when the rate of inflow of fluid is decreased. In the recovery room one should check that the bladder is adequately draining, if it is not this may indicate that a clot is blocking the eye of the catheter. The bladder should be promptly washed out using strict aseptic technique. The catheter should be changed by the surgeon. Only rarely is it necessary to return the patient to the operating room.

Secondary haemorrhage tends to occur after the patient has been discharged. All men should be warned about this possibility and given appropriate advice to rest and to have a high fluid intake. It is usually minor in degree, but if clot retention occurs, the patient will need to be readmitted, a catheter will have to be passed and the bladder washed out.

Perforation of the bladder or the prostatic capsule can occur at the time of transurethral surgery. This usually occurs from a combination of inexperience in association with a large prostate or heavy blood loss. If the field of vision becomes obscured by heavy blood loss, it is often prudent to achieve adequate haemostasis and abandon the operation, swallowing one’s pride on the understanding that a second attempt may be necessary. A large perforation with marked extravasation may require the insertion of a small suprapubic drain. Rectal perforation should be extremely rare.

Sepsis. Bacteraemia is common even in men with sterile urine and occurs in over 50 per cent of men with infected urine, prolonged catheterisation or chronic retention. Septicaemia can occur in these patients shortly after operation or when the catheter is removed. In men at high risk the use of prophylactic antibiotics is recommended. Wound infection following open prostatectomy is common if a urethral catheter has been in situ for a number of days before the operation. Perhaps the most worrying aspect of infection is the early rigor following surgery. If left undetected and untreated this may progress to frank septicaemia with profound hypotension. A blood culture should be taken and antibiotics given parenterally, e.g. amoxycillin plus cefuroxime.

Incontinence. Incontinence is inevitable if the external sphincter mechanism is damaged. The bladder neck is rendered incompetent by these operations and therefore an intact distal sphincter mechanism is essential for continence. Damage to the sphincter may occur at open prostatectomy and following transurethral surgery if the resection extends beyond the verumontanum. If pelvic floor physiotherapy is ineffective, then the only satisfactory treatment is the fitting of an artificial urinary sphincter. In some patients, detrusor instability contributes to the incontinence. The use of anti­cholinergic agents or imipramine may help.

Retrograde ejaculation and impotence — see previous section.

Urethral stricture. This may be secondary to prolonged catheterisation, the use of an unnecessarily large catheter, clumsy instrumentation or to the presence of the resectoscope in the urethra for too long a period. These strictures arise either just inside the meatus or in the bulbar urethra. An early stricture can usually be managed by simple bouginage but later on it may be necessary to cut the densely fibrotic stricture with the optical urethrotome. The routine use of an Otis urethrotomy prior to TURP reduces the incidence of postoperative stricture.

Bladder neck contracture. Occasionally a dense fibrotic stenosis of the bladder neck occurs following overaggressive resection of a small prostate. It may be due to the overuse of the coagulating diathermy. Transurethral incision of the scar tissue is necessary.

Reoperation

It is now known that after 8 years, 15—18 per cent of men with BPH will undergo repeat TURP (the rate after open prostatectomy is about 5 per cent). The reasons include a technically imperfect primary procedure and a speculative repeat operation in men with symptoms who are cystoscoped after operation.

General complications

Death occurs in about 0.2—0.3 per cent of men undergoing elective prostatectomy. In very elderly men, in men with prostate cancer admitted as an emergency with acute or chronic retention, or those with very large prostates the 30-day death rate may be in the order of 1—1.5 per cent.

Cardiovascular. Pulmonary atelectasis, pneumonia, myocardial infarction, congestive cardiac failure and deep venous thrombosis are all potentially life-threatening conditions that can affect this elderly and often frail group of men.

Water intoxication. The absorption of water into the circulation at the time of transurethral resection can give rise to congestive cardiac failure, hyponatraemia and haemolysis. Accompanying this there is frequently confusion and other cerebral events often mimicking a stroke. The incidence of this condition has been reduced since the introduction of isotonic glycine for performing the resections and the use of isotonic saline for postoperative irrigation. The treatment consists of fluid restriction.

Osteitis pubis is rare.

Newer treatments

In general, newer, minimally invasive treatments occupy a position intermediate between TURP and drug treatment. As yet, there are no long-term data on duration of effectiveness.

Microwave and laser treatments and other methods of tissue destruction

Microwave treatment aims at providing an external source of microwaves which are then focused within the prostate gland. The source may be within the rectum or the urethra, although recent machines use the intraurethral route. With the first-generation machines, the prostate heats to between 400C and 45”C (hyperthermia). There is very minimal tissue destruction and there is no rise in serum PSA, confirming that little of the prostate is damaged. Although there may be symptom improvement, there are no improvements in voiding pressures. The next generation of microwave machines is able to provide an increased source of energy which destroys some of the prostate (thermotherapy — temperature >500C). The outcome appears to be better than hyperthermia.

Laser treatments can be of several types. In one a noncontact probe is used to vaporize prostatic tissue under direct vision. There is no bleeding and this treatment can be used to carry out bladder neck incisions in men with small prostate glands as day-case treatment and a catheter may not be necessary. Hence this treatment would be potentially cost-effective in this setting. The cost of the probes at present, however, is £500, which would balance out any cost saving in terms of hospital stay. These probes are not useful in the treatment of men with large glands as the treatment would take too long.

Another type of laser is a contact side-firing laser of lower energy but greater penetration. This energy results in necrosis of the prostate gland to a varying thickness. The energy can by applied transurethrally under direct vision or transurethrally under the control of ultrasound. The potential advantage of the latter technique is that it means that greater energy can be applied to thicker areas of BPH, ensuring a more complete treatment. A suprapubic catheter is inserted for several weeks whilst the necrotic prostate sloughs — significant symptoms can occur during this period. There is little or no bleeding and the treatment can be given as a short-stay procedure or day-case procedure. Laser treatment, however, requires a general anaesthetic. The cost of the probes is about £400. A laser can be purchased for about £45000.

The outcome of contact laser treatment appears to be better than microwave hyperthermia, with improvement in flow rates from 9 to about 14 ml/second and improvement in symptom score by about 50 per cent. It is as yet unclear how effective it is in comparison to TURP in terms of cost-effectiveness, symptomatic and urodynamic outcome. Other types of laser treatment include interstitial laser therapy, which involves the insertion of laser probes into the substance of the prostate, and Holmium laser treatment. The latter approach involves excision of parts of the prostate using a cutting laser and then morcellating the excised prostate fragments which fall back into the bladder so that they can be removed.

There are newer methods of treatment becoming available including focused high-frequency ultrasound and direct treatment of the prostate with needles providing high-energy electromagnetic treatment. The outcome of these treatments is unknown

lntraurethral stents (Fig. 66.14)

These devices are helpful in the management of men with retention and who are grossly unfit (classified by the American Society of Anesthesiologists as ASA grade IV or V). These men are rare cases.