Page 1820 - Saunders Comprehensive Review For NCLEX-RN

and a high-protein diet.
5. An increased BUN/creatinine ratio occurs with fluid
volume excess.
E. Urinalysis
1. Description: A urine test for evaluation of the renal
system and renal disease (Table 54-1)
2. Interventions
a. Wash perineal area and use a clean
container for collection.
b. Obtain 10 to 15 mL of the first morning
voiding if possible.
c. Refrigerating samples may alter the
specific gravity.
d. If the client is menstruating, note this
on the laboratory requisition form.
F. A 24-hour urine collection
1. Check with the laboratory about specific instructions
for the client to follow, such as dietary or medication
restrictions.
2. Instruct the client about the urine collection.
3. At the start time, instruct the client to void and discard
that sample.
4. Collect all urine for the prescribed time (24 hours).
5. Keep the urine specimen on ice or refrigerated and
check with the laboratory regarding adding a
preservative to the specimen during collection.
6. At the end of the prescribed time, instruct the client to
empty the bladder and add that urine to the collection
container.
G. Specific gravity determination
1. Description: A urine test that measures the ability of
the kidneys to concentrate urine
2. Interventions
a. Specific gravity can be measured by a
multiple-test dipstick method (most
common method), refractometer (an
instrument used in the laboratory
setting), or urinometer (least accurate
method).
b. Factors that interfere with an accurate
reading include radiopaque contrast
agents, glucose, and proteins.
c. Cold specimens may produce a false
high reading.
d. Normal random reference interval is
1.003 to 1.030 (may vary depending on
the laboratory).
e. An increase in specific gravity (more

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