The primary advantage of peritoneal dialysis is
mobility. Most people are able to participate in
regular activities, including work, while peritoneal
dialysis is under way, provided the person can per-
form exchanges on the necessary time schedule
and there is a hygienic, private location where the
person can do the exchange. The success of peri-
toneal dialysis is more variable than that of
hemodialysis because the permeability of the peri-
toneum varies among individuals. Some doctors
believe peritoneal dialysis is less effective than
hemodialysis at clearing toxins from the body.
Benefits and Risks of Renal DialysisRenal dialysis is the difference between life and
death for people who have END-STAGE RENAL DIS-
EASE(ESRD). For most people, the benefits clearly
outweigh the potential risks and complications.
The primary risks related to renal dialysis are
infection, and, with hemodialysis, bleeding. Renal
dialysis becomes less effective over time because it
simply is not as effective as the body’s natural
mechanisms. A slow cascade of complications
arises. Dialysis only cleanses the blood; it cannot
restore kidney function or prevent further degen-
eration of the kidneys.
See also QUALITY OF LIFE.
renal failure The inability of the KIDNEYSto ade-
quately filter toxins from the body. Generally the
kidneys reach the point of renal failure when they
have less than 15 percent functional capacity.
Renal failure can be acute (occur suddenly) or
chronic (develop slowly over time). Though the
term failureimplies the condition is permanent,
but this is not necessarily the case. Most people
who experience acute renal failure fully recover
with appropriate treatment. When the deteriora-
tion of kidney function is progressive and irre-
versible, however, renal failure is not only
permanent but also eventually becomes complete.
This irreversible condition is END-STAGE RENAL DIS-
EASE (ESRD). A person who has ESRD requires
long-term RENAL DIALYSISor KIDNEY TRANSPLANTATION
to sustain life.
Acute renal failure Acute renal failure can
occur in response to any circumstance that over-
whelms the body, such as systemic INFECTION,
severe BURNS, or a toxic assault such as a DRUG
overdose or massive exposure to a nephrotoxin.
DEHYDRATIONand lack of BLOODflow to the kidney
(such as may occur with severe ATHEROSCLEROSISor
a blood clot) also can cause acute renal failure.
Acute renal failure may require short-term renal
dialysis to cleanse the blood while the kidneys
recover as well as appropriate treatment for the
cause of the renal failure.COMMON CAUSES OF ACUTE RENAL FAILURE
acute NEPHRITIS ALCOHOLpoisoning
DEHYDRATION DRUG OVERDOSE
extensive BURNS gentamicin
HEART FAILURE HEAT STROKE
HEMOLYTIC UREMIC SYNDROME LIVER FAILURE
major surgery multisystem failure
nephrotoxin exposure reaction to contrast dye
renal ischemia SEPTICEMIA
streptomycin traumaChronic renal failure Chronic renal failure
develops gradually over time, often years to
decades. The most common causes of chronic
renal failure are NEPHROPATHY of DIABETES and
nephropathy of HYPERTENSION (high BLOOD
PRESSURE). Other causes include long-term expo-
sure to NEPHROTOXINS, long-term daily use of
nephrotoxic drugs such as NONSTEROIDAL ANTI-
INFLAMMATORY DRUGS(NSAIDS) and other ANALGESIC
MEDICATIONS (PAIN relievers), notably codeine.
Chronic renal failure may also consist of repeated
bouts of acute renal failure that leave minor resid-
ual damage. Over time this damage becomes
cumulative, causing scarring in the nephrons that
impairs their ability to function. About 20 million
Americans live with chronic renal failure.COMMON CAUSES OF CHRONIC RENAL FAILURE
ALPORT’S SYNDROME chronicHYDRONEPHROSIS
DIABETES FANCONI’S SYNDROME
GLOMERULONEPHRITIS GLOMERULOSCLEROSIS
GOODPASTURE’S SYNDROME HEAVY-METAL POISONING
HYPERTENSION lupus NEPHROPATHY
organic solvent exposure POLYCYSTIC KIDNEY DISEASE
renal ARTERY ATHEROSCLEROSIS RENAL CANCER218 The Urinary System