SAMPLE COLLECTION.docx
- 1. SPECIMENS COLLECTION, TRANSPORT AND PROCESSING INTRODUCTION laboratory result quality outcome largely depends on the quality of the specimen submitted or collected. The best of specimen is that which has been appropriately selected, collected, and transported. If these are not a priority, then the laboratory can contribute little or nothing to patient care. Specimens should be rejected if there is a risk to the safety of a patient; i.e. occasions where there is concern for the identity of the specimen, the wrong container type, incorrect transport conditions, etc. However, it is always important to double check if a specimen COULD be accepted. This may involve processing the specimen so as not to compromise specimen integrity while also evaluating the specimen for acceptability. GUIDELINES General Guidelines for Proper Specimen Collection 1. Before collecting the specimen, consider the risk/benefit ratio of the collection procedure to the patient. Inadequate and/or inappropriately collected specimens for culture yield little useful clinical information and may actually be misleading. 2. Collect specimen before administering antimicrobial agents when possible. 3. Collect specimen with as little contamination from indigenous microflora as possible to ensure that the sample will be representative of the infected site. 4. Utilize appropriate collection devices. Use sterile equipment and aseptic technique to collect specimens to prevent introduction of microorganisms during invasive procedures. 5. Clearly label the specimen container with the patient’s name, identification number and/or date of birth. Include the date and time of collection, and source of specimen. 6. Collect an adequate amount of specimen. Insufficient amounts of specimen may yield false- negative results. 7. Inform the clinical microbiology lab when “rule-out” requests are important. Consider geographic location and season when notifying the laboratory of “rule-out” requests. 8. Identify the specimen source and/or specific site correctly so that proper culture media will be selected during processing in the laboratory. 9. If a specimen is to be collected through intact skin, cleanse the skin first. For example, use 70% alcohol followed by 10% povidone-iodine or chloroprep scrub. 10. Collect specimens in sturdy, sterile, screw-cap, leak-proof containers with lids that do not create an aerosol when opened. Safety Considerations for Collection and Transport of Specimens 1. Follow universal precaution guidelines. Treat all specimens as potentially hazardous. 2. Personnel must use appropriate barrier protection (such as gloves and laboratory coat or gown) when collecting or handling specimens. If splashing may occur, protective eyewear, face masks, and impervious aprons are also necessary. 3. Do not contaminate the external surface of the collection container and/or its accompanying paperwork.
- 2. 4. Minimize direct handling of specimens in transit from the patient to the laboratory whenever possible. Use plastic sealable bags with a separate pouch for the laboratory requisition orders or transport carriers. 5. Never transport syringes with needles to the laboratory. Instead, transfer the contents to a sterile tube or cup, or remove the needle, recap the syringe and place the syringe in a sealable, leak-proof plastic bag. General Guidelines for Proper Specimen Transport 1. Transport all specimens to the laboratory promptly to ensure the survival and isolation of fastidious organisms and to prevent overgrowth by more hardy bacteria. This will provide a more accurate diagnosis of the infectious-disease process. 2. Alternatives to prompt delivery. Many specimens may be refrigerated at 2-8ºC. CSF, blood cultures, stool cultures, anaerobic cultures, and specimens submitted on selective media for Neisseria gonorrhea should not be refrigerated. Refer to details below: a. If blood is drawn into blood culture broth, hold it at room temperature. b. Specimens that may harbor temperature-sensitive organisms such as Neisseria species should be left at room temperature. c. For anaerobic culture specimens, use anaerobic transport and maintain at room temperature. d. Stool Specimens—fresh specimens must be received in lab within one hour of collection or use transport kits with the following guidelines: (1) Enteric PCR specimen should be transferred into the orange top C&S vial within one hour of collection. (2) O&P specimen should be transferred into the black top vial within one hour of collection. (3) C. Difficile specimen should be refrigerated within one hour of collection. e. Hold CSF specimens at room temperature (unless they are to be cultured for viruses). f. All specimens for viral culture must be refrigerated. Use of Specimen Transport Systems 1. When using a swab for collection and transport of specimens, the test request should be considered prior to specimen collection. A specific type of swab may be necessary for the collection and transport of certain cultures. 2. Anaerobe transport systems are used to ensure the viability of anaerobic organisms in transit to the laboratory. The lab supplies two styles; one for fluids and a surgery pack for tissues. 3. Stool collection/transport systems are used to preserve stool specimens for ova and parasite exams. Stool specimens which will not reach the laboratory within one hour of passage must be preserved before organisms become distorted and/or disintegrate. Use Para-Pak transport system available from the lab. Specimen Acceptability 1. Specimens which have been improperly collected or transported may not be processed. Processing and reporting results from such specimens may provide misleading information that can lead to misdiagnosis and inappropriate therapy
- 3. 2. Listed below are unacceptable specimens/situations: a. Unlabeled specimen or mislabeled b. Leaking container or obviously contaminated c. Barium enema stool for O&P exam d. Prolonged transport e. Non-sterile container. f. No date and time of collection and/or no source. g. Anaerobe cultures on unsuitable specimens (e.g. stool, mouth, vaginal) h. Specimen unsuitable for request (e.g. Anaerobe culture request with specimen in aerobic transport) i. Syringes with needle attached. j. Quantity not sufficient 3. As per lab procedure for specimen acceptability, staff will contact ordering physician/nurse to request repeat specimen, suggest alternate order or transport requirement, and/or to obtain additional information, if needed. Be sure all situations are documented on laboratory Green Sheets. 4. It is always important to double check if a specimen COULD be accepted. This may involve processing the specimen so as not to compromise specimen integrity while also evaluating the specimen for acceptability.