Specimen Collection

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The crucial aspect of identifying pathogens responsible for infectious diseases is the correct collection, processing, and handling of specimens by healthcare professionals. These specimens include urine, blood, sputum, and feces and are essential in understanding the patient’s health status. As nurses, we are responsible for collecting and labeling specimens for analysis and ensuring their timely delivery to the laboratory. It is important to know the correct procedure for collecting specimens to safeguard ourselves and prevent the transmission of diseases.

Concepts of Specimen Collection

Specimen should be collected from the actual site of infection without contaminating adjacent tissues and secretions
Collect the specimen at the best time possible, such as early morning sputum for AFB culture
Use appropriate collection devices, such as sterile, leak-proof specimen containers, to collect ample amounts of samples
Use appropriate transport media, such as anaerobic transport vials or culturette for bacterial culture
Check expiration date before inoculating the collection device
Collect specimens before administration of antimicrobial agents whenever possible
Properly label the specimen and fill out the test request form completely
Lessen transport time and maintain an appropriate environment between the collection of specimens and delivery to the laboratory

Importance of Specimen Collection

Proper specimen collection is essential for accurate diagnosis, treatment, and monitoring of infectious diseases.
Improper specimen collection can lead to false-negative results, which can result in delayed or inappropriate treatment and increased risk of disease transmission.
Specimen collection techniques must be performed in accordance with established guidelines and protocols to minimize the risk of contamination and ensure the accuracy of test results.
Inadequate specimen volume, improper transport and storage conditions, and delays in delivery to the laboratory can also negatively impact test results.
In addition to affecting patient care and outcomes, poor specimen collection practices can also lead to increased healthcare costs due to repeated collections and unnecessary treatment.
Nurses and other healthcare professionals responsible for specimen collection must be trained and competent in the appropriate techniques and protocols to ensure quality patient care and outcomes.

Throat Swab Culture:

A laboratory diagnostic test to evaluate for the presence of bacterial or fungal infection in the throat.
Done to isolate and identify any pathogens, which may be medium.
Infections that can be detected include strep throat, pneumonia, tonsillitis, whooping cough, and meningitis.

Purpose:

Done to detect the presence of organisms in the throat that could cause infection.
Presence of group A streptococcus bacteria in the throat is a key sign of strep throat.

Supplies:

Sterile cotton-tipped applicator specimen collection tip (culturette)
Tongue depressor
Laboratory request form
Flashlight

Procedure:

Observe proper hand hygiene prior to the test.
Have the patient sit comfortably on a bed or chair.
Ask the patient to tilt their head back and say “Ahhh,” avoiding antiseptic mouthwash before the test.
Use a flashlight to light up the back of the throat and check for inflammation using the tongue depressor.
Swab the tonsillar areas from side to side, including any inflamed or purulent sites, and avoid touching the tongue, cheeks, or teeth with the applicator.
Immediately place the cotton-tipped applicator into the culture tube.
Label the culture tube with the patient’s name, SSN, and ward number if applicable.
Fill out the request form completely, including patient’s name, rank or status, family member prefix and sponsor’s social security number, ward number if inpatient or mobile number if outpatient, source of specimen (throat), any antibiotics the patient is taking, and date and time the specimen was obtained, and the name of the physician who ordered the culture.

Sputum Specimen and Culture

A sputum specimen is a laboratory diagnostic test that evaluates the presence of pathogens in the material expelled from the respiratory passages. The specimen is typically obtained by having the patient cough up mucus from the lungs, or through tracheal suctioning with an in-line trap or bronchoscope. Sputum specimens are often taken for three consecutive days due to the difficulty in obtaining an adequate sample at one time.

Purpose

A sputum specimen is obtained for culture to:

Identify the microorganism responsible for lung infections
Identify cancer cells shed by lung tumors
Aid in the diagnosis and management of occupational lung diseases.

Supplies and Equipment

Supplies and equipment required to collect a sputum specimen are:

Sterile container with a tight-fitting lid
Emesis basin
Box of tissues
Gloves
Goggles
Aerosol of 10% sodium chloride or sterile water (optional)
Nebulizer (optional)
Laboratory request form

Preparation

To prepare the patient, it is advised to have them drink enough fluids the night before the test, unless they are on fluid restriction, to increase sputum production overnight. For best results, the sample should be obtained first thing in the morning. If this is not possible, wait at least an hour after the patient has eaten breakfast. Ten to 15 ml of sputum is typically needed for laboratory analysis. If the patient cannot cough up a specimen, respiratory therapists can use sputum induction techniques.

Procedure

Observe proper hand hygiene and gather equipment.
Provide privacy for the patient and explain the entire procedure.
Position the patient in a chair or on the side of the bed. If they are not capable of sitting alone, place them in a high-Fowler’s position. Remove dentures, if applicable.
Have the patient rinse their mouth with clean water to remove any food particles. Do not allow them to brush their teeth or use mouthwash as it could kill bacteria in the sputum.
Don gloves and goggles. Uncap the container but avoid touching the inside to ensure that it’s sterile.
Instruct the patient to take three deep breaths, then force a deep cough and expectorate into a sterile screw-top container. Keep the container closed until the patient is ready to spit into it to prevent contamination by particles in the air.
If you do not get an adequate sample on the first try, have the patient continue to cough until you can collect a minimum of 15 ml. If the patient has trouble bringing up secretions, have them breathe into the nebulizer and try again.
Once the specimen is collected, securely cap the container. Remove and discard gloves and wash hands thoroughly. Allow the patient to rinse out their mouth and provide a tissue.
Record the amount, consistency, and color of the sputum collected, as well as the time and date in the nursing notes.
Send the sample to the lab immediately without refrigeration.

Guaiac Fecal Occult Blood Test (gFOBT)

The guaiac fecal occult blood test (gFOBT) is a test used to detect the presence of hidden (occult) blood in the stool. It is the most common type of fecal occult blood test used today.

Purpose

The purpose of the guaiac fecal occult blood test (gFOBT) is to identify the presence of blood in the stool that is not visible. Guaiac is used as a reagent to detect the presence of occult blood.

Supplies and Equipment

The supplies and equipment needed to perform the guaiac fecal occult blood test (gFOBT) include:

Test kit (with detailed instructions)
Test cards
Brush or wooden applicator
Gloves

Preparation

Before the test, instruct the patient not to eat red meat, any blood-containing food, cantaloupe, uncooked broccoli, turnip, radish, or horseradish for 3 days. The patient may also need to stop taking certain medications, such as vitamin C and nonsteroidal anti-inflammatory drugs like aspirin and ibuprofen, that can interfere with the test. However, the patient should not stop any medication without consulting the physician. This test involves only normal bowel function and should not cause any discomfort.

Procedure

To perform the guaiac fecal occult blood test (gFOBT), follow these steps:

Explain the test and procedure to the patient and instruct them to prepare themselves when they feel the urge to have a bowel movement.
Ask the patient to collect a sample from their bowel by placing a sheet of plastic wrap or paper loosely across the toilet bowl to catch the stool or using a dry container to collect the stool.
Advise the patient not to mix the sample with urine and to flush the remaining stool down the toilet. Remind the patient not to take samples from the toilet bowl water.
Instruct the patient to use the wooden applicator or brush to smear a thin film of the stool sample onto one of the slots in the test card or slide.
Next, ask the patient to collect a specimen from a different area of the same stool and smear a thin film of the sample onto the other slot in the test card or slide.
Close the slots and put the name of the patient and the date on the test kit.
Instruct the patient to repeat the test on their next two bowel movements to improve the accuracy of the test.
Remove gloves and wash hands thoroughly.
Send the specimen to the laboratory.
Inform the patient that they may resume their usual diet and medications as ordered.

Urine Specimen and Culture

The physical appearance of urine is the first aspect assessed:

Color The color of normal urine ranges from pale yellow to deep amber depending on its concentration. The type and amount of waste present in the urine determine its color. Certain foods and medications contain pigments and other compounds that can alter the color of urine. Blood in the urine gives it a red color, and if there is a large amount of blood, the urine may appear red. During a chronic nephritis flare-up, the small number of red blood cells in the urine causes it to have a smoky appearance.

Odor Normally, urine has a faint smell. If urine is left standing, bacterial decomposition creates an ammonia-like odor. The consumption of certain foods, such as beets or asparagus, can give urine a distinctive smell. Urinary tract infections (UTIs) may cause urine to have a foul odor. If urine is not going to be examined right away, refrigeration is recommended.

Random Urine Sample

A random urine sample is a specimen of urine that can be collected at any time during the day. This type of sample is the most convenient to obtain and may be used to detect the presence of various substances in the urine at one particular point in the day. Generally, no special handling is required with these samples.

Supplies and Equipment

Clean, dry container with lid
Cotton ball or towelette
Laboratory request form

Procedure

Instruct the patient to use the cotton ball or towelette to clean the urethral area thoroughly to prevent external bacteria from entering the specimen.
Allow the patient to void into the container.
Label the specimen container with patient identifying information and send it to the lab immediately. Delay in examining the specimen may cause a false result when bacterial determinations are to be made.
Wash your hands and instruct the patient to do the same.
Note that the sample was collected.

Midstream “Clean-Catch” Urine Specimen:

A midstream “clean-catch” urine specimen is a common way to collect urine samples from adults, especially men, without the need for catheterization. It is important to follow the “clean-catch” protocol to obtain an uncontaminated sample and accurate test results.

Purpose:

The clean-catch urine method is used to prevent contamination of the urine sample with germs from the genital area. It is a method of collecting a urine sample for various tests, including urinalysis, cytology, and urine culture.

Supplies and Equipment:

To collect a midstream “clean-catch” urine specimen, you will need a sterile specimen cup, Zephiran, a soap solution, or three antiseptic towelettes, three cotton balls (to use with Zephiran or soap solution), and a laboratory request form.

Preparation:

Explain to the patient that this type of urine collection involves first voiding approximately one half of the urine into the toilet, urinal, or bedpan, then collecting a portion of midstream urine in a sterile container, and allowing the rest to pass into the toilet. Discuss that this is done to detect the presence or absence of infecting organisms and must be free from contaminating matter that may be present on the external genital areas.

Procedure:

For female patients:

Wash your hands with soap and water.
Instruct the patient to clean the perineal area with towelettes or cotton balls.
Tell the patient to separate the folds of the urinary opening with thumb and forefinger and clean inside with towelettes or cotton balls, using downward strokes only. Keep the labia separated during urination.
Instruct the patient to void a small amount of urine into the toilet to rinse out the urethra, void the midstream urine into the specimen cup, and the last of the stream into the toilet. The midstream urine is considered to be bladder and kidney washings, which is the portion that the physician wants to test.
Fill out the laboratory request form completely, label the specimen container with patient identifying information, and send it to the lab immediately. A delay in examining the specimen may cause a false result when bacterial determinations are to be made.
Wash your hands and instruct the patient to do the same.
Note that the specimen was collected, and record any difficulties the patient had or if the urine had an abnormal appearance.

For male patients:

Wash your hands with soap and water.
Instruct the patient to completely retract the foreskin and cleanse the penis with towelettes or cotton balls.
Instruct the patient to void a small amount of urine into the toilet to rinse out the urethra, void the midstream urine into the specimen cup, and the last of the stream into the toilet. The midstream urine is considered to be bladder and kidney washings, which is the portion that the physician wants to test.
Fill out the laboratory request form completely, label the specimen container with patient identifying information, and send it to the lab immediately. A delay in examining the specimen may cause a false result when bacterial determinations are to be made.
Wash your hands and instruct the patient to do the same.
Note that the specimen was collected, and record any difficulties the patient had or if the urine had an abnormal appearance.

Note: If the urine sample is being taken from an infant, use a clean-catch kit that consists of a plastic bag with a sticky strip on one end that fits over the baby’s genital area, as well as a sterile container. Use the same cleaning methods and the plastic bags for collecting the urine.

Timed Urine Specimens

Including 2-hour, 4-hour, and 24-hour collections, are commonly used for urine chemistry procedures. A 24-hour urine collection involves collecting all of a person’s urine in a special container over a 24-hour period, starting with an empty bladder, to assess kidney function and detect disease.

Purpose

A timed urine collection is a noninvasive way to evaluate kidney function and detect disease by measuring the total amounts of waste eliminated by the kidneys.

Supplies and Equipment

Large, clean bottle with cap or stopper
Measuring graduate
Bedpan or urinal
Refrigerated storage area
Gloves

Preparation

The test is simple and does not require any special preparation, other than collecting urine in the provided container over a specific period.

Procedure

Label the bottle with patient identifying information, the date, and time the collection begins and ends.
Instruct the patient to urinate and discard the first voided urine upon waking up in the morning.
Collect all subsequent urine in the special container over the next 24 hours, storing it in a cool environment such as a refrigerator or cooler with ice.
Instruct the patient to drink adequate fluids during the collection period.
Record each amount of urine on the intake and output (I&O) sheet and emphasize proper hand hygiene before and after each collection.
After exactly 24 hours from the start of the collection, ask the patient to void again to complete the specimen collection.
Instruct the patient to keep the collection container refrigerated until it is delivered to the laboratory.
Send the bottle and laboratory request form to the lab.

Example: To begin a 24-hour urine collection, the patient should void and discard the urine at 7:00 am and collect all urine voided over the next 24 hours in the special container, including the urine voided at 7:00 am the next day. The container should be kept refrigerated until it is delivered to the laboratory.

Pregnancy Urine Test

Description

This test measures the level of a hormone called human chorionic gonadotropin (HCG), which is produced during pregnancy, in the urine. It can detect the hormone as early as 10 days after conception.

Purpose

This test is commonly used to determine if a woman is pregnant, and is best taken after she has missed her period.

Supplies and Equipment: Only a urine specimen cup is required.

Preparation

The patient should wait one to two weeks after her first missed period to get the most accurate results. It’s important to note that irregular periods or miscalculations of when a period is due can affect the test, and around 10 to 20 percent of pregnant women may not detect their pregnancy by testing on what they believe to be the first day of their first missed period.

Procedure

Instruct the patient to use the test the first time she urinates after waking up, as this urine is the most concentrated and will contain the highest hCG levels of the day.
Label the specimen cup with the patient’s identifying information, complete a laboratory request form requesting an HCG test, and send both to the lab.
Only the physician or a registered nurse should inform the patient of the test results.

Blood cultures

Are a common test used to identify the presence of harmful organisms in a patient’s blood, typically for those with unexplained fever. The test is a simple blood draw and is done to determine which specific organism is causing the problem and how to best treat it.

Supplies and Equipment

Sterile syringe (20 cc) and three needles (usually 20 gauge)
Two blood culture bottles (one for anaerobic and one for aerobic specimens)
Betadine solution or alcohol swab
Sterile cotton balls or gauze pads
Gloves
Tourniquet
Band-aid
Chux (to protect the bed)
Laboratory request form

Preparation

The patient needs little preparation for this test. The patient may need to stop taking certain medications that may alter the blood culture results.

Procedure

Explain the procedure and its purpose to the patient.
Gather all necessary equipment at the patient’s bedside.
Assist the patient to a comfortable position, and ask for help from the team if needed.
Observe proper hand hygiene.
Clean the tops of both culture bottles with betadine solution or alcohol swab.
Put on gloves and clean the drawing site with betadine solution or alcohol swab.
Apply the tourniquet to allow the veins to fill with blood and become more visible.
Draw at least 10 cc of blood from the patient (5 cc for each bottle).
Remove the needle while applying pressure to the venipuncture site with a cotton ball or gauze pad.
Replace the needle with another sterile needle.
Inject 5 cc of blood into the anaerobic bottle and 5 cc into the aerobic bottle.
Gently mix the blood with the solution in both bottles.
Label both bottles with the patient’s identifying information and the type of culture (aerobic or anaerobic).
Fill out the laboratory request form completely and send the specimens to the laboratory immediately.
Secure a band-aid or some gauze over the puncture site.

Nurses have a crucial role in the hospital setting when it comes to collecting, labeling, and ensuring timely delivery of specimens to the laboratory. Therefore, it is important for nurses to have a good understanding of the hospital’s policies and procedures regarding specimen collection. In addition to having the necessary knowledge, nurses should also possess the required skills and understanding to perform procedures in compliance with the organization’s protocols, policies, and guidelines.