General Collection

clip_image002_0000SPECIMEN COLLECTION GUIDELINES

Policy

The quality of laboratory tests is dependent on many variables, with one being the quality of the specimen submitted. The specimens should be properly collected, labeled, packaged and transported to the laboratory in a timely manner. These steps, when properly followed, will maintain sample integrity and are prerequisites for accurate testing.

Specific collection and handling requirements for specimens sent to a referral laboratory, will be followed according to the laboratory website, test directory and/or client service department.

Product Preparation

  1. Prior to collecting the specimen, review the specimen requirements listed in the test listing section of this manual. Make sure that the minimum blood draw volume is collected, to avoid patient complications associated with excessive venipunctures and to avoid increased hazardous waste.
  2. Ask the patient to identify himself/herself.
  3. Each specimen must be accompanied by a properly completed test requisition form. It is important that the patient’s sex, age and/or birth date be indicated so that applicable age-adjusted normal values can be provided. The requisition form should include:
    1. Patient name
    2. Requesting Physician
    3. Date and time of collection
    4. Birth date
    5. Sex
    6. Diagnosis
    7. Patient address and phone number
    8. All insurance information
    9. Source of specimen (where applicable)
    10. Date of last menstrual period (where applicable)
  4. CLIA regulations require that we receive physician signatures on additional tests ordered or test changes not accompanying the original request form. This must be completed and faxed at the time of the request or immediately following the request. All requests must be returned no later than 30 days after a verbal request has been made. See appendix A for sample form.
  5. Specimens shall be labeled with at least 2 identifiers at the time of collection. The patient last name, first name and DOB is preferred. It is very important to meet this requirement and essential to patient and sample identification at the time of specimen collection. In the event that this requirement is not met, communication and follow-up may be done through written memos, phone calls, and/or visits by account managers.

BLOOD COLLECTION

SST Tube (Serum Separator)

Tube does not contain an anticoagulant, but contains a clot activator and serum gel separator. This tube is used for collecting serum for most tests requiring serum. Follow the instructions below for specimen preparation:

  • Perform venipuncture as with any other blood collection vehicle.
  • Invert the tube gently no more than five times (further inversion may cause alterations in sample integrity).
  • Do not remove the stopper at any time. Allow the blood to clot for at least 30 minutes but not longer than 1 hour. Do not centrifuge immediately after drawing blood.
  • Centrifuge at 2200-2500 RPM for at least 15 minutes.

Plain Red-Top Tube

Tube does not contain an anticoagulant. This tube is used for collecting serum or clotted whole blood specimens. Follow the instructions below for specimen preparation:

  • Perform venipuncture as with any other blood collection vehicle.
  • Do not remove the stopper at any time. Allow the blood to clot for at least 30 minutes but not longer than 1 hour. Do not centrifuge immediately after drawing blood.
  • Centrifuge at 2200-2500 RPM for at least 15 minutes.

Lavender-Top Tube (EDTA)

Tube contains EDTA as an anticoagulant. This tube is used for preparing EDTA plasma, whole blood and specimens. Note: Tube should be inverted several times immediately after blood collection in order to prevent blood coagulation. Follow the instructions below the specimen preparation:

  • Plasma:
    • Perform venipuncture as with any other blood collection vehicle.
    • Invert the tube gently no more than five times to mix blood and additive.
    • Centrifuge within 1 hour of collection at 2200-2500 RPM for at least 15 minutes.
  • Whole Blood:
    • Collect whole blood according to the instructions provided for the individual test. Thoroughly mix the blood with the additives by gently inverting the tube. Maintain the specimen at room temperature.

Light Blue-Top Tube

Tube contains sodium citrate as an anticoagulant. This tube is used for preparing plasma for coagulation studies. Follow the instructions below for specimen preparation:

  1. Obtain venous blood by drawing a clearing tube prior to obtaining the specimen. Draw the specimen in a light blue top sodium citrate tube. Avoid stasis and contamination of the specimen by tissue thromboplastin.
  2. Mix blood with anticoagulant (3.2% sodium citrate) by gentle inversion. Use 0.5 mL sodium citrate for every 4.5 mL blood. An exact ratio of 9 parts blood to 1 part coagulant should be maintained.

Therapeutic Drug Monitoring-Patient Preparation Guidelines

Carbamazepine: Collect as a trough just prior to next dose.

Digoxin: Collect as a trough just prior to next dose.

Phenobarbital: Collect as a trough just prior to next dose.

Phenytoin: Collect as a trough just prior to next dose.

Theophylline: Collect as a trough just prior to next dose.

Valproic Acid: Collect as a trough at least 1 hour prior to next dose.

Gentamicin: Collect Trough sample just prior to next dose. Collect Peak sample 1-2 hours after completion of 60 minute IV infusion.

Tobramycin: Collect Trough sample just prior to next dose. Collect Peak sample 1-2 hours after completion of 60 minute IV infusion.

Vancomycin: Collect Trough sample just prior to next dose. Collect Peak sample 1-2 hours after completion of 60 minute IV infusion.

NOTE: Please document patient dose time on the test requisition to ensure proper evaluation of Therapeutic Drug Levels, as applicable. Dosing times will be noted in the patient report.

UREA BREATH TEST COLLECTION

  1. Collect baseline sample by having the patient inhale, hold their breath for 4-5 seconds, them exhale into the blue bag. Write patient name and DOB on both collection bags prior to use.
  2. Thoroughly mix the entire Pranactin-Citric packet with water in the plastic container. The patient must drink the solution using the plastic straw provided.
  3. Wait 15 minutes, and then collect the second breath sample in the pink bag using the same procedure as Step 1.
  4. Place caps tightly on the bags to prevent sample loss. Samples are good for 7 days after collection. Fill out the date and time as well as marking the blue bag as baseline and the pink bag as sample.

Patient Preparation:

  • The patient should have no food or drink for at least 1 hour before testing.
  • The patient should not have taken antimicrobials, proton pump inhibitors (PPIs) or bismuth preparations for 2 weeks prior to the test.
  • Remind the patient that Pranactin-Citric contains phenyalanine (one of the protein components of Aspartame). Phenylketonurics restrict dietary phenylalanine.

Post Collection:

  1. After collection and completing all the information required on the collection bags, place in the clear bag provided.
  2. If you order in 4medica you will order test code 8425.
  3. On the 4medica req. please clearly write, Breath test performed by Biotech (for billing purposes. Do not place 4medica labels on the pink or blue bags.
  4. If you do not order in 4medica, please clearly write the test code 8425 next to the test and Breath test performed by Biotech.
  5. Send the specimen into the lab via courier.

URINE COLLECTION:

Random urine collection

Submit a first morning specimen whenever possible. Urine for pregnancy testing should be a first morning void, or a random specimen with a specific gravity of at least 1.010. To reduce contamination, the specimen submitted for urinalysis should be a clean catch midstream sample. Refrigerate all specimens within 1- 2 hours and hold there until laboratory transport is available.

24-Hour Urine Collection

Proper collection and preservation of 24-hour urine specimens is essential for accurate test results. Patients must be carefully instructed in the correct procedure, give Attachment B form.

Give a collection container and detailed instructions to the patient. If a urine preservative is required, it is important to place the preservative in a urine collection container at the start of the collection. Caution the patient that the preservative may be toxic and caustic and that it should not be spilled or discarded. Mix the urine well, measure the volume of the 24-hour collection and record volume on both the test request form and the transport vial.

Note: For those analyses requiring the addition of 6N HCI or other preservatives, add the preservative at the start of collection. Have the patient collect each specimen in a smaller container and carefully pour the urine into the 24-hour container to avoid any possible acids burns to the patient. See Appendix B for Patient Instructions.

MICROBIOLOGY SPECIMEN COLLECTION

Blood Cultures

Blood Cultures require only one bottle capable of recovering Aerobic and Anaerobic bacteria, therefore only 1 SPS Vacutainer needs to be drawn. Blood cultures should be drawn before the administration of antibiotics, if possible. They should be collected in SPS vacutainer tubes using aseptic technique (Tubes will be transferred over to blood cultures bottles once they arrive at the laboratory). If at all possible, blood cultures should not be drawn from lines, but should be drawn via venipuncture.

NOTE: It is imperative the phlebotomists are properly trained to use sterile techniques for drawing and handling of blood culture specimens. These steps include the use of iodine on the SPS tube as well as on the patient.

  • Recommended volume:
    • Children – 1 to 5 ml of blood
    • Adults —- 10 ml of blood for 1 bottle
  • Recommended number and timing:
    • Two or three cultures drawn at one-hour intervals. (Limit of three sets per 24 hours.)
    • Two cultures may be obtained, one immediately after the other, from separate sites.

Catheter Tip

Cleanse the skin around the catheter site with alcohol. Aseptically remove catheter and clip 5 cm of distal tip directly into a sterile tube or screw-cap container. Store at room temperature until laboratory transport is available.

Fluids

Prior to collection, the overlying skin should be disinfected with iodine. The specimen should be collected via percutaneous needle aspiration or surgery. Always submit as much fluid as possible; never submit a swab dipped in fluid. Specimen can be transported in an anaerobic transport system, sterile screw-cap tube or blood culture bottle for bacteria. A volume of at least >1ml is required. Specimen can be stored at room temperature until laboratory transport is available.

Genital Cultures

Genital culture specimens (vaginal, penile, cervical, urethra, etc.) should be collected using a swab transport system. Swabs can be stored at room temperature until laboratory transport is available. Only one swab per patient per day should be submitted. NOTE: If strep screen is the only test ordered, only the presence or absence of beta-hemolytic streptococcus will be resulted. If the presence of other pathogens is desired, another culture type should be ordered.

For Group B Strep screens the lower vagina, followed by the rectum (insert swab through the anal sphincter) using the same or two different swabs. Note: Cervical, perianal, perirectal or perineal specimen are not acceptable and a speculum should not be used for Group B Strep screen cultures. Swab should be placed into a non-nutruitive transport medium (Aimes or Stuart and refrigerated if possible).

Please note: Patients who are allergic to penicillin should be evaluated for anaphylaxis. If a woman is determined to be at high risk for anaphylaxis susceptibility testing for clindamycin and erythromycin should be ordered. So when ordering a Group B Strep screen please make note on the requisition if the patient is allergic to penicillin and a high risk for anaphylaxis.

GC/CT DNA PROBES

C.trachomatis and N.gonorrhoeae can be detected in the following specimens: endocervical and male urethral specimens and in female and male urine specimens. Only the swabs and the transport tubes contained in the APTIMA Unisex Swab Specimen Collection Kit for Endocervical and Urethral Swab Specimens can be used to collect patient swab specimens. Swab specimens must be transported to the laboratory in the swab specimen transport medium and tube. Swab specimens must be transported to the laboratory at 2 to 30 C and tested within 60 days of collection. Urine specimens can be transported to the laboratory at 2 to 30 C in either the primary collection device (urine cup) or in the urine specimen transport tube. Urine specimens must be transferred into the GEN-PROBE specimen transport tube within 24 hours of collection and before being assayed.

Occult Blood

Occult blood specimens should be collected using the “Coloscreen” kits, or by sending in a bulk stool specimen in a sterile container with a securely fitting cap. Each kit contains patient instructions. It is very important that patients are instructed to apply the specimen on the correct side of the Coloscreen card, and not to over inoculate. Tests CANNOT be performed on specimens that are improperly inoculated. Each kit contains three cards (one card per bowel movement). Specimens can be stored at room temperature until laboratory transport is available. One “Coloscreen” kit per day should be submitted.

Ova and Parasite Testing

The appropriate specimen is sent in the Para-Pak line of parasitology products, or a bulk stool specimen can be sent in a sterile contain with a securely fitting cap. These should include either PVA (mercury free) or SAF for a permanent stain and 10% formalin or “empty” container to which 10% formalin can be added. A minimum of 4 grams or 4 tablespoons of specimen is necessary.

Pinworm

The most effective way of diagnosing pinworm infections is by the recovery of eggs or female worms from the perianal region. The gravid female worm migrates, in the evening, to the perianal region and deposits her eggs. Best sampling occurs in the morning just after waking, before bathing or a bowel movement. Specimens can be stored at room temperature until laboratory transport is available.

Specimen Collection:

  • “Scotch Tape Method”
    • Attach one end of a length of clear scotch (NOT frosted) to a wooden tongue depressor, sticky side up. Loop the tape around the end of the stick.
    • Loop the tape right around the stick and turn the end under and attach to the opposite side of the stick.
  • The “Pinworm Paddle” is by far the definitive method of pinworm collection. It is easy to use, self-contained and requires less handling by the person sampling and by the laboratory making it a safer method. Like the scotch tape preparation it involves a sticky surface. The adhesive is however, applied to just one side of the paddle shaped applicator.

Sputum Cultures

A first morning specimen from a deep productive cough is ideal. The patient should rinse their mouth or gargle with water, before specimen collection, to remove excess oral flora. At least 1-3cc of specimen should be collected in a sterile container. Only one specimen per day should be submitted. Specimens should be refrigerated until laboratory transport is available. NOTE: 24 hour sputum specimens are not acceptable for culture.

Stool Cultures

The specimen of choice is the diarrheal stool collected during the active state of the disease. Pathogens are more likely to be present in large numbers during active disease. Formed stools are less likely to yield etiologic agents.

  • Specimens should be collected into transport container with securely fitting top, or a container with >2g of Cary-Blair holding medium.
  • Patient instruction is necessary to insure good specimen quality control:
    • Do NOT contaminate with urine.
    • Do NOT retrieve from the toilet.
  • A minimum of 1 to 2 grams or 1 to 2 tablespoons is sufficient for all EXCEPT Ova and Parasite testing.
  • Two or three specimens, submitted on separate days (one/day), will increase the probability of isolating a pathogen. Accept no more than 2 specimens per patient without prior consultation with an individual who can explain the limited yield provided by an additional specimen.
  • Culture swabs are acceptable ONLY for culture.
  • Specimens should be stored in the refrigerator until laboratory transport is available.
  • Fecal leukocyte specimens should be stored at room temperature until laboratory transport is available, NOT in the refrigerator.
  • Order a Clostridium difficle test on all patients over 6 months with clinically significant diarrhea and a history of antibiotic exposure.
  • Consider C. difficle testing as an alternative to routine microbiology studies for inpatients over 6 months who have test requests for routine enteric pathogens.

Throat and Nasal Cultures

A swab of the suspected area with a dry, sterile swab from a transport system should be collected, returned back to the plastic sleeve and the swab should be pushed firmly into the bottom of the sleeve to release transport medium onto the swab.

  • Cultures will always be screened for normal respiratory pathogens (i.e. beta-hemolytic strep, Haemophilus spp., etc.).
  • Swabs can be stored at room temperature until laboratory transport is available.
  • Only one specimen per day should be submitted.
  • If the presence or absence of beta- hemolytic strep is required request “Strep A Rapid w/Reflex to Culture”. The specimen should be ordered as a STAT and will have a “Rapid-A” ran on them. If the Rapid A is negative, then a culture will be set up to determine the presence or absence of other types of beta strep.

Trichomonas

Vaginal secretions, and prostatic secretions are acceptable specimens for trichomonas examination. Secretions should be collected with a cotton tipped swab and immediately immersed in a tube of Diamond’s media. The organisms are susceptible to the cold and therefore must NOT be refrigerated. Specimens can be stored at room temperature until laboratory transport is available. NOTE: Trichomonas are less likely to be present in urine; therefore, urine samples for trichomonas examination are discouraged.

Urine Cultures

Collect only clean catch, midstream urine specimens in a sterile container. Proper collection is essential for reliable culture results and proper patient collection instruction is the only way this is accomplished. A minimum of > 1ml of urine should be collected. Refrigerate all specimens immediately and hold there until laboratory transport is available.

Wound and Abscess Cultures (Ear, Eyes, etc)

Wound and abscess cultures should be collected using a swab transport system. Swabs can be stored at room temperature until laboratory transport is available. One specimen per day, per source should be submitted.

  • If open: Aspirate, if possible, or pass a swab deep into the lesion to firmly sample the lesions’ “fresh border”
  • If closed: Aspirate abscess matter with needle and syringe: aseptically transfer all material into anaerobic transport device.

NOTE: If the nature of the wound requires screening for anaerobic organisms it must be collected in an anaerobic transport system. Request “Anaerobic Culture”. In addition, a wound culture should be ordered for aerobic organisms. Swabs can be stored at room temperature until laboratory transport is available.