Specimen Collection

Introduction

Proper sample collection and handling is an integral part of obtaining a valid and timely laboratory test result. Specimens must be obtained using proper phlebotomy techniques, collected in the proper container, correctly labeled (in the presence of the patient) and promptly transported to the laboratory. It is the policy of the laboratory to reject samples when there is failure to follow these guidelines. All specimens should be handled with universal precautions, as if they are hazardous and infectious.

Patient Preparation

Prior to each collection, review the appropriate test description, including the specimen type to be collected, the minimum volume required, the procedure, the collection materials, and the storage and handling instructions.

Specimen Collection Timing

The basal state (the early morning approximately 12 hours after the last ingestion of food) is recommended for determining the concentration of body constituents such as glucose, cholesterol, triglycerides, electrolytes, and proteins.

Blood composition is significantly altered after consuming food, and consequently alters many clinical chemistry tests. For outpatients, provide the patient in advance with appropriate collection instructions and information on fasting, diet, and medication restrictions when necessary.

Patient Identification

All patients from whom clinical specimens are obtained must be positively identified prior to specimen collection. Positive identification is the responsibility of the person collecting the sample.

Identify the patient prior to sample collection, using at least two patient identifiers. Verify the patient's name, unit history number on the identification armband (inpatients and ER), or drivers' license or other ID (outpatients) with the information on the requisition. Refer to IHOP 09.13.24 Patient Identifiers for additional requirements.

Precaution: Maintain awareness for sound-alike names and suffixes during patient identification. (i.e. Gonzalez and Gonzales; Sr. and Jr.)

Inpatients: Patients in the hospital should be wearing an identification bracelet that includes their last and first name, date of birth and a unique hospital number. Proper identification should include a three-way match using information on the ID bracelet and the test requisition, and the patient's stating of his or her name. If the patient does not have an ID bracelet, ask the nurse responsible for the patient to positively identify the patient and to place and ID bracelet on the patient. For unconscious or unidentified patients, it is important a unique number or identification system be used.

Outpatients: For an outpatient or ambulatory setting, there is no ID bracelet, but the patient should have been given identification labels when he/she registered. This label can be used along with asking the patient his/her name. If there is no label, then another means of identification should be used. Use at least two patient identifiers whenever taking blood samples.

DO NOT collect any specimen unless at least two positive identifications can be made.

Universal Precautions

All specimens should be regarded as potentially hazardous or infectious. Universal Blood and Body Fluid precautions should be observed.

Test Request Criteria

The test requisition (paper or electronic) must include the following. Hand written requisitions must be legible.

  • the patient's first and last name
  • a unique identification number which assures positive patient identification (e.g., UH number)
  • patient sex
  • the unit/clinic location
  • the name(s) and signature of the authorized provider requesting the test(s)
  • UTMB physician identification number (if applicable)
  • the test(s)/procedure(s) being ordered
  • the date (including day, month, and year) and time of specimen collection is required on all orders (paper or electronic) or on the actual specimen container
  • name or initials of person collecting specimen is required on all orders (paper or electronic) or on the actual specimen container
  • pager/ phone number of appropriate contact person
  • office address of requesting physician if not part of the UTMB enterprise
  • diagnosis: ICD10 code or narrative description
  • source of the specimen, when appropriate
  • date of last menstrual cycle (for gynecologic specimens)
  • clinical Information, when appropriate
  • blood bank request forms must include the identity of the phlebotomist

    Labeling Criteria

    All specimens submitted to Laboratory Services for testing must be appropriately labeled to assure positive identification and optimum integrity of patient specimens from the time of collection until testing is completed and the result reported. In accordance with standards issued by the College of American Pathologists (CAP), American Association of Blood Banks, and The Joint Commission, all specimens must be labeled at the time of collection; in the presence of the patient, to maintain identity throughout the pre-analytical, analytical, and post-analytical processes. Refer to LS I.1.02.01 Specimen Labeling and Requests for Testing for additional requirements.

    Orders (paper or electronic) will be checked carefully upon receipt in the laboratory and must match the specimen to be acceptable for testing.
    All primary specimen containers must be labeled with two identifiers at the time of collection.  If a second patient identifier used is not listed below, then approval to process the specimen must be obtained from the division Medical Director (not applicable to Blood Bank).

  1. UTMB Specimens (Non-Blood Bank) must be labeled with the patient’s full first and last name and at least one of the following additional unique identifiers:
  • Patient’s medical record number
  • Offender patient ID number
  • UNOS number
  • Date of birth
  • Sample ID (accession number)
  1. Blood Bank Specimens must be labeled with both of the following unique identifiers:
  • Patient's full name (first and last) and
  • Medical record number.

NOTE:  Alternative identifiers are NOT accepted for blood bank specimens.

  1. Non-UTMB Specimens may have patient’s first and last name and one other unique identifier. Acceptable unique identifiers are:
  • Date of Birth
  • UNOS
  • TDCJ Offender ID
  1. Outside Consults may be accepted with patient’s first and last name, one additional patient identifier (date of birth, sample ID, medical record number) and a copy of the report from the referring hospital.
  2. All secondary specimen containers (including slides, blocks, and aliquots) are labeled with the patient’s first and last name and at least one of the following additional unique identifiers:
  • Patient’s medical record number
  • Offender patient ID number
  • UNOS number
  • Date of birth
  • Sample ID (accession number)

Aliquots are also labeled with the specimen type.


Specimen Collection

Prioritize Collection:

"STAT" means special turnaround time and must be collected immediately. It may involve a patient whose medical condition has suddenly become very critical and must be treated as a medical emergency.

Fasting: Requests for "fasting" specimens are performed before routine requests, so patients can eat meals on schedule.

Order of Draw

Blood collection tubes must be drawn in a specific order to avoid cross-contamination of additives between tubes. The recommended order of draw for is demonstrated below: (click image for larger view)

Order of Draw

Note: Tubes with additives must be filled to their stated volumes and thoroughly mixed. Erroneous test results may be obtained when the tube is not filled to the stated volume and blood is not thoroughly mixed with the additive. . When using a winged blood collection set for venipuncture and a coagulation (citrate) or lavender (EDTA) tube is the first specimen to be drawn, a discard tube should be drawn first. The discard tube (a non-additive or coagulation tube) must be used to displace the air in the collection set’s tubing, but does not need to be filled completely. Mix all tubes with anticoagulant by gentle inversion according to the chart above. Mix all tubes with anticoagulant by gentle inversion according to the chart above.