666
U N I T 7
Kidney and Urinary Tract Function
(see Table 27-1).
19
They include the use of drugs that
increase sphincter tone in stress incontinence, decrease
hyperexcitability of the detrusor muscle in overactive
bladder/urge incontinence, or relieve outflow obstruc-
tion in overflow incontinence.
Surgical intervention may be considered when
other treatment methods have proved ineffective.
The principal objective of surgical treatment of stress
incontinence is to increase outlet resistance through
restoration of the proper suspension and support of
the vesicourethral segment of the urethra.
23
A mini-
mally invasive procedure for the treatment of stress
incontinence due to internal sphincter weakness is the
periurethral injection of a bulking agent.
8,19
Surgically
implanted artificial sphincters are available for use
in treatment of incontinence due to severe sphincter
damage.
8
Other procedures remove outflow obstruc-
tion to reduce overflow incontinence and detrusor
muscle instability.
Special Needs of Elderly Persons
Urinary incontinence is a common problem in elderly
persons, both male and female.
30–33
Incontinence
increases social isolation, frequently leads to institu-
tionalization, and predisposes to infections and skin
breakdown. Many factors contribute to incontinence
in elderly persons, including a reduction in bladder
capacity and urethral closing pressure. Detrusor mus-
cle function also tends to change with aging. There is
often a reduction in the strength of bladder contrac-
tion and impairment in emptying that leads to larger
PVR volumes. Detrusor overactivity is also common.
It is characterized by symptoms of immediate urinary
urgency and frequency and, in the case of involuntary
urinary loss, urge incontinence. In men, benign prostatic
hyperplasia may lead to outlet obstruction and overflow
incontinence.
34
Men may also develop stress inconti-
nence following radical prostatectomy for treatment of
prostate cancer or transurethral resection for treatment
of benign prostatic hyperplasia. In each of these cases,
bladder pressure exceeds the closure pressure at the ure-
thral outlet, leading to urine leakage.
Furthermore, advancing age often results in restricted
mobility, comorbid illness, infection, and constipation
or stool impaction, all of which can precipitate urinary
incontinence. Many elderly persons have difficulty get-
ting to the toilet in time. This can be caused by arthri-
tis that makes walking or removing clothing difficult or
by failing vision that makes trips to the bathroom pre-
carious, especially in new and unfamiliar surroundings.
Impaired thirst or limited access to fluids can lead to
constipation, in which the impacted stool produces ure-
thral obstruction, causing overflow incontinence.
Medications prescribed for other health problems
may also contribute to incontinence. Potent, fast-act-
ing diuretics are known for their ability to cause urge
incontinence. Diuretics, particularly in elderly persons,
increase the flow of urine and may contribute to incon-
tinence, particularly in persons with diminished bladder
capacity and in those who have difficulty reaching the
toilet in time. Drugs such as hypnotics, tranquilizers,
and sedatives can interfere with the conscious inhibition
of voiding, leading to urge incontinence.
Many nonurologic conditions predispose the elderly
to urinary incontinence. The transient and often treat-
able causes of urinary incontinence may best be remem-
bered with the acronym DIAPPERS, in which the
D
stands for dementia/dementias,
I
for infection (urinary
or vaginal),
A
for atrophic vaginitis,
P
for pharmaceuti-
cal agents,
P
for psychological causes,
E
for endocrine
conditions (diabetes),
R
for restricted mobility, and
S
for
stool impaction.
32
These eight transient causes of incon-
tinence should be identified and treated before other
treatment options are considered.
As with urinary incontinence in younger persons,
incontinence in elderly persons requires a thorough his-
tory and physical examination to determine the cause
of the problem. A voiding history is important. A void-
ing diary provides a means for the person to provide
objective information about the number of bathroom
visits, the number of protective pads used, and even the
volume of urine voided. A medication history is also
important because, as just noted, medications can affect
bladder function.
Treatment of incontinence in the elderly usually starts
with conservation measures before considering the use
of medications or surgery. Conservative treatment may
involve changes in the physical environment so that the
person can reach the bathroom more easily or remove
clothing more quickly. Habit training with regularly
scheduled toileting—usually every 2 to 4 hours—often
is effective. The treatment plan may require dietary
changes to prevent constipation or a plan to promote
adequate fluid intake to ensure adequate bladder fill-
ing and prevent urinary stasis and symptomatic urinary
tract infections.
SUMMARY CONCEPTS
■■
Disorders of bladder structure and function
include urinary obstruction with retention or
stasis of urine, and urinary incontinence with
involuntary loss of urine. Both types of disorders
can have their origin in the structures of the lower
urinary tract or in the neural mechanisms that
control their function.
■■
In lower urinary tract obstructive disorders,
urine is produced normally by the kidneys
but is retained in the bladder, a condition that
predisposes to kidney damage. Obstructions can
be classified according to their location (bladder
neck, urethra, or external urethral meatus),
cause (congenital or acquired), degree (partial or
complete), and duration (acute or chronic).
