Management of men with benign prostatic hyperplasia or bladder outflow obstruction
Strong indications for treatment (usually
prostatectomy) include:
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
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
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
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
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
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
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
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
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
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.