Chapter 2: URINE SPECIMEN STORAGE AND HANDLING Flashcards
Containers for urine specimen collections must be…
clean
dry
made of a clear or translucent disposable material such as plastic or glass
Container
They should stand upright, have an opening of at least______, and have a capacity of_______.
A lid or cover that is easily placed onto and removed from the container is needed to prevent_____.
Specimens that are transported require a lid with a leakproof seal.
Disposable, nonsterile containers are commercially available and economical.
4 to 5cm
50 to 100 mL
spillage
Container
For the collection of specimens for microbial culture, sterile, individually packaged urine containers are available from commercial sources.
However, when a urine specimen must be stored for_______ before testing, the use of a sterile container is recommended, regardless of the tests ordered, because of changes that can occur in unpreserved urine.
2 hours or longer
Container
Various large containers are available for the collection of 12-hour and 24-hour urine specimens for quantitative analyses.
These containers have a capacity of approximately_______ and have a______ and ______.
Usually made of a_______, they protect the specimen from ultraviolet and white light, and acid preservatives can be added to them.
3000 mL
wide mouth and a leakproof screw cap
brown, opaque plastic
Container (pediatric)
C,P,P… urine collection bags are available for collecting specimens from the pediatric patient.
These collection bags can be purchased as nonsterile or sterile.
After collection, they are self-sealing for transport to the laboratory.
Clear, pliable, polyethylene
Container (pediatric)
For collection of a 24-hour specimen, some brands provide an______ attached to the bag base.
This port enables transfer of the urine that has accumulated to another collection container, thereby eliminating the need for multiple collection bags.
More important, this exit port avoids repeated patient preparation and reapplication of adhesive to a child’s sensitive skin.
exit port or tubing
Labeling
All specimen containers must be labeled ________ after collection.
Because lids are removed, the patient identification label is always placed_______. Under no circumstances should the label appear only on the removable specimen lid. This practice invites specimen mix-ups; once the lid is removed, such a specimen is technically unlabeled.
before or immediately after
directly on the container holding the specimen
Labeling
Labels must have an adhesive that_____ and ______. The patient identification information required on the label may differ among laboratories.
resists moisture and adheres under refrigeration
Labeling
However, the following minimal information should be provided on all labels: (5)
the patient’s full name
a unique identification number
the date and time of collection
the patient’s room number (if applicable)
and the preservative used, if any
Urine specimens should be delivered to the laboratory immediately after collection. However, this is not always possible; if a delay in specimen transportation is to______, precautions must be taken to preserve the integrity of the specimen, protecting it from the effects of light and room temperature changes.
be 2hours or longer
Preservation
Changes in the physical examination result from
(1) alteration of the urine solutes to a different form, resulting in a color change;
(2) bacterial growth causing an increased odor because of metabolism or proliferation of bacteria; and
(3) solute precipitation in the form of amorphous material, which decreases urine clarity.
Preservation
Physical Changes
• Urine solutes can break down or change form, altering the____.
• Bacterial growth increases____ due to bacterial metabolism.
• Solutes may form amorphous precipitates (e.g., crystals), making the urine____.
color
odor
cloudy
Chemical changes
Key chemicals like____ may degrade, falsely lowering their levels.
• Nitrite increases as bacteria convert______
• pH rises as bacteria break down______
glucose
nitrate to nitrite
urea into ammonia
Preservatives
Unfortunately, no single urine preservative is available to suit all testing needs.
Hence the preservative used depends on the type of collection, the tests to be per-formed, and the time delay before testing.
The easiest and most common form of preservation,________, is suitable for the majority of specimens.*
refrigeration at 4°C to 6°C
Preservation
Any urine specimen for microbiological studies should be______ promptly if it cannot be transported directly to the laboratory.
This prevents bacterial proliferation, and the specimen remains suitable for culture for up to_____
refrigerated
24 hours
Preservation
Although refrigeration is the easiest means of preserving urine specimens, refrigeration of routine urinalysis specimens is not recommended if they will be analyzed within_______
Refrigeration can induce______ of amorphous urate and phosphate crystals that can interfere substantially with the microscopic examination.
2 hours.
precipitation
Timed collection
Timed specimens, particularly 12-hour and 24-hour collections, may require the addition of a_____ preservative to maintain the integrity of the analyte of interest.
chemical
Timed collection
Each urinalysis laboratory must have in its procedure manual a protocol for the collection of all timed urine specimens. The protocol should include
the name of the analyte;
a description of the appropriate
specimen collection technique;
the appropriate preservative required;
labeling requirements, including precautions for certain chemical pre-servatives;
the location at which the test is performed; reference ranges;
and the expected turnaround time.
Timed urine collections should be transported to the laboratory as soon as possible after completion of the collection.
The total volume is determined, the specimen is well mixed to ensure homogeneity, and aliquots are removed for the appropriate tests. At no point during a timed collection can urine be removed or discarded, even if the volume is recorded. This would invalidate the collection because the concentration of the analyte in any removed aliquot cannot be determined and corrected for.
At times it is necessary to verify that the fluid present in a urine container is in fact urine. This may occur in laboratories that perform urine testing for______. In these situations, particularly when the urine collection is not witnessed, the individual may have the opportunity to add a substance to the urine collection (e.g., an adulterated specimen).
Another possibility is that the liquid in the container is not urine.
illicit drugs (e.g., amphet-amine, cocaine, tetrahydrocannabinol [THC], steroids)
(3) can be helpful in identifying urine specimens to which additional liquid has been added.
Specific gravity, pH, and temperature
The physiologically possible range for urine pH in a fresh urine specimen is ________and
for specific gravity is_______.
In a normal healthy individual, the temperature of a urine specimen immediately after collection is usually between________
4.0 to 8.0
1.002 to 1.035
32.5°C and 37.5°C.
Note that urine specific gravity can exceed 1.035 if the patient has had a recent infusion of______
radiographic contrast media (x-ray dye).
Occasionally, when an amniocentesis is performed, concern may be raised regarding whether the fluid collected is_____ or ______
Another circumstance that may be encountered is receipt in the laboratory of two specimens from the same patient in identical sterile containers for testing, but the fluid source is not clearly evident on either container.
In these varied situations, a few simple and easily performed tests can aid in determining whether the fluid is actually urine.
amniotic fluid or urine aspirated from the bladder.
