chapter 52 specimen collection

Copyright © 2012 Wolters Kluwer Health | Lippincott Williams & Wilkins

Chapter 52

Specimen Collection

Chapter 52

Specimen Collection


In Practice: Collecting Specimens and SamplesIn Practice: Collecting Specimens and Samples

Refer to Nursing Care Guidelines 52-1.


Nursing AlertNursing Alert

• Always wear clean gloves when collecting specimens of urine, stool, sputum, wound drainage, or blood.

• Thorough and consistent handwashing before and after any contact with clients and their specimens limits spread of microorganisms that cause disease.

• It also protects the specimen from inadvertent contamination by the nurse’s hands.


The Urine SpecimenThe Urine Specimen

• Information obtained

– Client’s recovery or decline

– Assessment of kidney and/or liver status

– Presence of legal and illegal drugs

– Pregnancy

– Identification of specific disease-causing organisms


Keeping Intake and Output RecordsKeeping Intake and Output Records

• Indicator of nutritional and fluid balance.

• Order is given to “record food and fluid intake” or “I&O + calorie count.”

• Over 24 hours, a person’s normal fluid I&O will be approximately the same, or balanced.

• Amounts recorded for I&O are measured in milliliters (mL).


Key ConceptKey Concept

• Some normal situations can cause the fluid intake and output to be quite different.

• For example, during very hot weather, fluid is lost through perspiration, but it cannot be measured.

• Eating extra salt may cause a temporary retention of water in the tissues.


Fluid Intake and OutputFluid Intake and Output

• Fluid intake

– All fluids consumed through the gastrointestinal (GI) system

– Fluids taken as part of intravenous (IV) therapy or total parenteral nutrition (TPN)

• Fluid output

– Includes all fluids excreted from the body by any means

• Maintain IV fluids record.


Measuring Fluid IntakeMeasuring Fluid Intake

• Measure all fluids

– Enteral intake: by gastrointestinal (GI) system

• By mouth

• Count ice as ½ water

• Tube feeding

– Parenteral intake: peripheral lines (not GI system)

• Intravenous (IV) therapy

• Total parenteral nutrition (TPN)


Measuring OutputMeasuring Output

• Measure

– Urine

– All other fluids leaving body

• Wound drainage

• Emesis

• Watery diarrhea

• Bleeding

• Returns from nasogastric (NG) suction tube



• Before giving fluids to a client, find out if the client is on I&O. Do not fill a water pitcher or empty one unless you are sure of the procedure used for recording I&O in your facility.

• Do not empty a bedpan or urinal without first finding out if the client’s I&O is being recorded or if a urine specimen is required.

• Enlist the aid of the client or family, when possible, to assist with tracking intake and output and reporting when the water pitcher is empty or when the client has voided (urinated).


Key ConceptKey Concept

• The urinary output of an infant or incontinent adult can be determined in several ways:

– A special specimen collection bag can be used. These are also available for adults, but are rarely used.

– The infant diaper, Depends-type adult diaper, or sanitary napkin can be weighed and compared to the weight of the same item when dry. The weight can then be converted, using a chart, to urine volume.

• Urine specimens can be collected in the same manner

– Specimen hat.


Measuring Urine Specific GravityMeasuring Urine Specific Gravity• Urine specific gravity

– An indicator of the concentration of urine as compared with pure water

– Measured with a urinometer or hydrometer

• Normal range

– 1.010 (dilute) to 1.025 (highly concentrated)

– High specific gravity could indicated dehydration of fluid retention

– Low specific gravity could indicate a disorder such as diabetes insipidus or excessive use of diuretic medications


Collecting Urine Specimens for ExaminationCollecting Urine Specimens for Examination

• Urinalysis

– Components of urine identified

• Urine specimens are collected

– At the beginning of treatment

– When illness is present

– To check for the presence of legal or illegal drugs

– To determine a pregnancy

– To check for infection



• Place all specimens in leak-proof containers.

• Keep the outside of these containers clean and dry.

• Place them into plastic biohazard bags for transport to the laboratory.

• Label containers before use. In some facilities, you must also label the bag.

• Be sure to include the appropriate lab request form, so the laboratory staff knows which tests to complete.

• In many facilities, the request is entered on the computer as well.


In Practice: Collecting Clean-Catch or Midstream Urine SpecimensIn Practice: Collecting Clean-Catch or Midstream Urine Specimens• *Refer to Nursing Care Guidelines 52-3.

• Label container

• Instruct client to cleanse the urethral area thoroughly

• Instruct female client to cleanse from front to back and to cleanse each side with a separate wife, saving the last for the urethral area itself

• Instruct the male client to cleanse the penis using a circular motion and going outward from the urethral meatus

• Instruct client to then void a small amount into the toilet and then void into the sterile container (catching the midstream urine), then void the remainder into the toilet



• In some cases, such as when doing drug testing, an observed urine specimen must be obtained.

• In this case, the nurse must actually observe the client voiding into the specimen container.

• Be aware that there are a number of methods used to avoid detection when giving a false urine specimen.

• If you are expected to obtain accurate urine samples for drug testing, you will require special inservice education.


In Practice: Collecting a 24-Hour Urine SpecimenIn Practice: Collecting a 24-Hour Urine Specimen

• Refer to Nursing Procedure 52-4.

• Discard the first void and document the time


Collecting the Fractional Urine SpecimenCollecting the Fractional Urine Specimen

• Determines amounts and characteristics of urine during various periods (“fractions”) of the day

– Often obtained for 6 hour periods

• Collect specimens according to hospital policy

or

• Refer to collection method in text

• Store all specimens on ice or in a specimen refrigerator during 24 hour urine collection period


An Indwelling CatheterAn Indwelling Catheter

• Take care not to allow the collecting bag to be elevated above the level of the bladder.

• Obtaining a one-time catheterized urine specimen

– Residual urine volume

• Strict sterile technique

• 40% of all nosocomial infections are related to infections of the urinary tract.



• Strict sterile technique must be followed in doing catheterization to prevent urinary tract infections.

• The Centers for Disease Control reports that 40% of all nosocomial infections are related to infections of the urinary tract.


The Stool SpecimenThe Stool Specimen

• Provides information about the functioning of the GI system and its accessory organs

• Two common tests

– Occult blood = “hidden” or unseen blood

– Ova and parasites (O&P)

• Indicates presence of intestinal parasites (worms) or their eggs (ova)


The Stool Specimen, cont.The Stool Specimen, cont.

• Hemoccult or Hematest

– A test for occult (hidden) blood in stool or body secretions

– May need to scrape feces out of attends/diapers using a tongue depressor to obtain a specimen

– NEVER leave the Hemoccult solution bottle in the client’s room—it can cause blindness if accidentally used as an eye drop. (Most containers look like an eye drop container!)

– Observe smear for a blue discoloration

• Guaiac

– Substance that causes the tested occult blood to change color


Nursing AlertNursing Alert• Be aware that false-positive results may occur with guaiac tests.

• “False-positives” can be caused by the client having consumed large amounts of rare red meat or certain foods, such as radishes, tomatoes, beets, horseradish, or some melons.

• In addition, the client should not take more than 250 mg per day of vitamin C and should not take aspirin or nonsteroidal anti-inflammatory drugs (NSAIDs) for 3 days before the test.

• Usually, three separate specimens are collected on three separate days before a determination of positive or negative is made. If test results are repeatedly positive, additional examinations are necessary.


Sputum SpecimenSputum Specimen

• Used to determine presence of tubercle bacillus (causative organism for tuberculosis)

• Obtain soon after client awakens in the morning

– Sputum accumulates in airways at night

• Expectorate = to cough up secretions

• Document sputum amount, color and consistency

• Label container appropriately with date, time, amount, color, consistency and time sent to lab



• The sputum specimen is considered highly contaminated. Treat it with caution.

• Paper tissues used by any client also are considered contaminated. Dispose of them properly.

• Wear gloves when handling tissues and sputum specimens and when providing nursing care if the client is coughing up sputum.

• Goggles and a mask or full face shield may be necessary to protect the nurse from droplet secretions, particularly if the client is coughing or spitting. (A “spit shield” is also available. This is a net-type device that is placed over the client’s head so he or she cannot spit at others.)


The Blood SpecimenThe Blood Specimen

• Taken at admission to healthcare facility

• Assesses blood’s normal cells and other components

• Determines presence of abnormalities or disease organisms

• Venipuncture

– Puncture of a vein, usually with a needle

– Blood often drawn in the AC space, jugular or femoral vein is used in children


The Blood Specimen, cont.The Blood Specimen, cont.

• Blood culture

– Identifies disease-causing organism

– Draw BC’s prior to antibiotic therapy!

• Drug sensitivity test

– Determines medications that will kill or arrest the growth of that organism

• C&S = culture and sensitivity


The Blood Specimen, cont.The Blood Specimen, cont.

• Nurses who draw blood need specialized instruction and supervised practice in venipuncture.


NURSING PROCEDURESNURSING PROCEDURES

• 52-4

• 52-5

• 52-6

• 52-7

chapter 52 specimen collection

Documents