BIOLOGICAL SPECIMEN COLLECTION
APPENDIX G
a. Critical elements for accuracy in analysis of physiological specimens are correct collection, handling, and transportation techniques. The quality of any analytical evaluation is directly related to the quality of the specimen and the degree of post-collection degradation that occurs prior to testing. Actual specimen collection procedures involving humans and animals are performed by HSS personnel; HSS personnel also coordinate for follow-on testing at the supporting medical facility. Environmental samples for suspect NBC hazards/agents may be collected and submitted by TOE units outside the AMEDD. Essentially all military operations, multinational deployments, military contingency operations, humanitarian support missions, and civic action programs will generate some laboratory testing requirements. Each scenario, geographical region, population base, and desired analyte will impact on the type of specimen(s) required and the collection process. During SOF or humanitarian operations, express permission is required before collecting specimens from civilians because of religious or sociological beliefs in many cultures. To obtain such specimens without permission could result in unnecessary mission complications.
b. Coordination for follow-on testing is absolutely critical to the specimen collection process. The quantity, type, preservation, and acceptable delay in the time from collection to testing must be established before any specimen is collected; otherwise, the effort will likely be compromised (to the detriment of both the individuals concerned and the authority awaiting the results).
c. In all cases, coordination with the receiving test facility must be made to establish sample requirements, preferred collection techniques, methods of preservation, and transportation conditions. Individual patient specimens submitted to an MTF that will also receive the patient is coordinated with the MTF¼s clinical laboratory section.
d. The number of individuals that need to be sampled varies considerable with the type of analysis performed and the impact of the values determined. For example, a background exposure survey is being conducted; a large number of individuals exposed in varying degrees to the environment is sampled to generate a valid database. Specific individual exposure (particularly to suspected NBC hazards/agents) would employ a different sampling model that involves a more refined specimen distribution scheme (including both suspected exposure cases as well as matched control specimens, if available).
(1) The number and types of individuals that need to be sampled, as well as the types of specimens required, is determined by the analytical needs of the testing facility and the nature of the information required.
(2) Analysis to predict the prevalence, incidence, and impact of health hazards will be coordinated by the Epidemiology Section of the AML. Their expertise and data analysis capability will guide the specimen procurement process to best meet the requirements of each particular scenario.
(3) The number and types of "control" specimens required to validate test information is determined by AML personnel. Random sampling, matched control populations, or other techniques will be employed as the requirements are identified.
(4) Confounding variables, interindividual variance, time-sequence significance, and other factors affecting analytical results are evaluated by the testing facility to predict their impact on results. The need to compensate for such variables is determined by AML personnel; sampling methods are adjusted accordingly to mediate their impact, as much as possible.
(5) Before submitting physiological specimens to a laboratory for analysis, coordination with the receiving laboratory is essential. Most routine specimen requirements can be verified through SOPs and submission manuals, but unusual or unique situations normally require direct contact with the testing laboratory to confirm the number and types of specimens required to effect an accurate analytical process.
G-2. Specimen Collection, Preservation, and Transport
a. Antemortem Specimens. Physiological specimens from living human or animal patients can include blood, urine, cerebrospinal fluid, feces, sputum, gastric secretions, bone marrow, organ tissue, and just about any other conceivable body source or excreted by-product. It must be noted that specimen types are seldom interchangeable; the exact type and amount of specimen required for a specific assay must be known before a collection procedure is initiated.
(1) Blood specimens represent the most common analytical sample requirement. Certain techniques and special care must be exercised to ensure an acceptable specimen is collected and to minimize an adverse affect to the patient or specimen collector. In general, the phlebotomy requires the use of a 20 to 22 gauge needle to minimize mechanical hemolysis during aspiration and either a syringe or Vacutainertm tube collection system. Blood collected with a syringe and needle should be transferred to an appropriate Vacutainertm tube immediately after collection. The type of tube, type of anticoagulant or preservative, and amount of blood collected will vary with the specific assay requested. Unless some special sample preparation step is required, the blood is best left in the original rubber stoppered tube for transport.
(2) Urine specimens are best collected using a clean-catch (mid-stream, if possible) technique in a sterile urine cup. Again, sample volume will vary somewhat with specific assay techniques; however, 25-50 ml is sufficient for most test requests.
(3) Tissue specimens can originate from many sources: skin, bone marrow, nail clippings, hair, surgical biopsy of internal tissues, or other orifices accessible by scrapping, swabbing, or minor excision. Tissue specimens are generally collected by primary health care providers, or individuals trained for this task.
NOTE:
In cases where the supporting laboratory cannot be contacted, as a minimum the following specimens should be collected: Urine:25 to 50 ml in a sterile container. Blood:one 7 to 10 ml tube without anti-coagulant (red-stoppered Vacutainertm); one 7 to 10 ml tube with potassium or sodium EDTA (lavender-stoppered Vacutainertm).
(4) All specimens (regardless of physiological source) must be labeled to positively identify the individual or animal from whom it was collected; at a minimum the individual's full name, unique personal identification number (SSN when possible), military unit or location, and date of collection should be written on the label of the specimen container.
(5) All specimens should be collected, handled and transported using acceptable aseptic techniques. Proper personal protection guidelines should be adhered to when collecting or processing specimens; this includes gloves, mask, gown, or other items appropriate for the specimen or situation. Common sense and the clinical and/or tactical situation will determine the extend of personal protection necessary.
(6) Preservation of specimens, either chemically or mechanically (cooling), may be necessary for certain specimen types, or specific assays to minimize the amount of analyte degradation that occurs after removing the specimen from its physiological microenvironment. The optimal preservation technique will vary with different laboratory tests and must be confirmed for each requested assay. While freezing may preserve some serum constituents, it will completely destroy certain microorganisms. This caution also applies to tissue specimens since "fixing" tissue with a standard 10 percent formalin solution will preserve tissue for special staining techniques; however, it renders the specimen completely useless for bacterial and fungal culture. Always verify specimen preservation requirements for storage and transport with the receiving laboratory (MTF or AML) before processing the specimen; ideally, confirmation of the correct handling conditions should be done before collection.
(7) The importance of coordinating specimen collection with the supporting laboratory facility cannot be overstated. When doubts exist about the appropriate source, collection technique, storage and preservation conditions, and transportation requirements for a specimen contact the receiving laboratory for instructions. Extremely small volumes of a specimens, properly collected and handled, can yield a tremendous amount of information to assist in making medical, tactical, and even strategic decisions. Conversely, very large quantities of poorly collected and insufficiently preserved specimens are essentially worthless for most analytical techniques.
(8) Analysis beyond intratheater capabilities will be coordinated by the AML, when deployed, or through hospitalization channels in the absence of the AML.
b. Postmortem and Forensic Specimens. The analysis of specimens from deceased humans and animals can provide valuable information about the disease, organisms, injuries, or environmental conditions at the time of death. This information can greatly enhance the treatment of others affected by the same, or physiologically similar, process. Specimen collection for postmortem or forensic examination is very important; the techniques involved reflect a significant degree of training, experience, and skill.
(1) The collection of specimens from remains should be conducted exclusively by a pathologist, or other personnel specifically trained in forensic collection techniques. An exception is when SOF personnel are operating under radio silence conditions; the most qualified medical person with the operation collects specimens for evaluation. However, correct specimen preservation techniques must be followed to ensure valid testing can be accomplished.
(2) A large amount of support information can be gained by analyzing the site of injury and subsequent death. This "site scene" investigation requires a tremendous attention to detail and a trained observer. If forensic personnel cannot be contacted, or will be unduly delayed in arriving at the scene, then photographs of the victim and the immediate surroundings should be made. The scope and extent of the photographs should be composed to reflect as much detail as possible to assist forensic personnel in reviewing the scene retrospectively. In the event that photography is not feasible, detailed sketches of the scene should be made to assist the forensic investigation.
(3) Techniques such as cardiac or bladder puncture, needle biopsy of organs, spinal tap, or exploratory laparotomy should not be performed by untrained personnel unless specifically requested and directed by forensic investigators.
c. Specimen Transport. Specimens submitted for laboratory analysis must be properly packaged and shipped to ensure they arrive in an analytically acceptable condition.
(1) Coordination must be made to determine the best method of transporting the specimen to the laboratory. If cooling is necessary, ice (wet or dry depending upon required temperature) must not be in direct contact with the specimen(s); it is placed in plastic bags, or other such material to cool the specimen during transit. Conversely, the specimen (or packing container) may need to be insulated to minimize temperature extremes during shipping.
(2) All specimens should be sealed in plastic bags, or other containers to prevent leakage during transport. This prevents loss of specimens, as well as minimizing the risk of contamination to receiving personnel.
(3) The chemical composition of specimens can rapidly deteriorate when exposed to excess heat, solvents, sunlight, and even ambient air. Likewise, microorganisms will not survive even relatively short periods of time if not kept at the correct temperature and, optimally, contained in a supportive transport medium. Instructions for packaging and transport conditions should be obtained from the receiving laboratory facility (MTF based or AML). Special transport medium, if necessary, is requested from the receiving laboratory, when it is not readily available to the collecting unit.
(4) As mentioned previously, accurate and complete specimen identification is necessary. An adhesive label on the primary specimen container is best, along with a list of all specimens packaged in a secondary transport container, if more than one specimen is being shipped.
(5) A short written narrative of the facts, circumstances, and conditions generating the specimens should be included with the shipment. This provides useful information to the laboratory investigators; it can guide them in expanded or follow-on testing.
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