Page 1819 - Saunders Comprehensive Review For NCLEX-RN

1. The prostate gland surrounds the male urethra.
2. The prostate gland contains a duct that opens into the
prostatic portion of the urethra and secretes the
alkaline portion of seminal fluid, which protects
sperm.
K. Risk factors associated with renal disorders (Box 54-1)
II. Diagnostic Tests
A. See Chapter 10 and Box 54-2 for information regarding normal
values for renal function studies.
B. Determination of serum creatinine level
1. Description: A test that measures the amount of
creatinine in the serum. Creatinine is an end product
of protein and muscle metabolism.
2. Analysis
a. Creatinine level reflects the glomerular
filtration rate.
b. Kidney disease is the only pathological
condition that increases the serum
creatinine level.
c. Serum creatinine level increases only
when at least 50% of renal function is
lost.
C. Determination of blood urea nitrogen (BUN) level
1. Description: A serum test that measures the amount of
nitrogenous urea, a byproduct of protein metabolism
in the liver.
2. Analysis
a. BUN levels indicate the extent of renal
clearance of urea nitrogenous waste
products.
b. An elevation does not always mean that
renal disease is present.
c. Some factors that can elevate the BUN
level include dehydration, poor renal
perfusion, intake of a high-protein diet,
infection, stress, corticosteroid use,
gastrointestinal (GI) bleeding, and
factors that cause muscle breakdown.
D. BUN/creatinine ratio
1. The BUN level is divided by the creatinine level to
obtain the ratio.
2. When the BUN and serum creatinine levels increase at
the same rate, the ratio of BUN to creatinine remains
constant.
3. Elevated serum creatinine and BUN levels suggest
renal dysfunction.
4. A decreased BUN/creatinine ratio occurs with fluid
volume deficit, obstructive uropathy, catabolic state,

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