Momentum Health follows standards of testing that align with the World Health Organization (WHO) Guidelines on Drawing Blood: Best Practices in Phlebotomy.
Preparing the patient and the specimen according to the correct guidelines will ensure the highest quality of laboratory testing. Once the patient is properly prepared, the specimen can be collected for processing, packing, and transportation in a timely manner and according to correct environmental conditions.
Specimen requirements include information such as specimen volume, collection and transport containers as well as transport temperature. If additional information is needed for the interpretation of the test results or there are specific instructions for patient preparation, they are listed along with specimen requirements. It is critical that an adequate specimen volume is submitted for analysis. The volume requested in this directory is enough for initial analysis as well as for any confirmatory tests that must be performed. If an inadequate specimen is submitted, we may not be able to perform the initial test or required confirmatory procedures.
If repeat or confirmatory tests cannot be performed, the report will indicate that the specimen quantity submitted was “QNS” (Quantity Not Sufficient) for additional testing. When serum or plasma is to be submitted for analysis, it is good practice to collect a volume of blood that is 2 to 2.5 times the volume of serum or plasma needed for the test. As an example, if 4 mL of serum or plasma is needed for a test, collect 8 to 10 mL of blood. When an inappropriate specimen or unclear test request has been submitted, you will receive notification with instructions for resolving the problem.
HEALTH AND SAFETY PRECAUTIONS
Use universal precautions when handling specimens containing blood or other potentially infectious material. Work areas contaminated with blood or serum must be disinfected immediately with 10% bleach (hypochlorite at 0.5% final concentration) or other approved disinfectant. In the event of an exposure, administer first aid immediately, notify your manager or supervisor and seek prompt medical attention. First aid includes washing cuts and needle sticks with soap and water; flushing splashes to the nose, mouth, or skin with copious amounts of water; and irrigating eyes with clean water, saline, or sterile irrigants.
Specimens must be handled in a safe manner and according to applicable legal requirements or guidance. Information on safe specimen handling may be obtained from the U.S. Occupational Safety and Health Administration (OSHA) and the Centers for Disease Control and Prevention (CDC). In handling human specimens, the goal is to protect health care workers and ancillary staff such as transportation as well as the general public from exposures to blood and to other potentially infectious body fluids. Besides following other specimen preparation procedures, prior to sending a specimen, ensure that there is no leakage from or visible contamination outside the specimen container and that there are no needles or other sharps in the package that could cause injury or pathogenic exposure to anyone handling or opening the package and inner containers.
When taking blood, health workers should wear well-fitting, non-sterile gloves, and should also carry out hand hygiene before and after each patient procedure, before putting on gloves and after removing them. The blood should be taken in a dedicated location that ensures patient comfort and privacy. To remove the risk of environmental contamination with pathogens, counter and work surfaces, and chair arms should be cleaned with disinfectant at the start of each shift and when visibly dirty. To prevent infections and other adverse events, health workers should follow the guidelines on patient identification, hand hygiene, use of gloves, skin disinfection, use of appropriate blood-sampling devices and safe transportation of laboratory samples. Patient consent and cooperation are important components of respecting patient rights. A patient information leaflet or poster that explains the procedure in simple terms is helpful.
HEALTH WORKER PROTECTION
One way to reduce accidental injury and blood exposure among health workers is to use safety (i.e. engineered) devices such as retractable lancets, syringes with needle covers or retractable needles and, when appropriate, plastic laboratory tubes. Another approach is to eliminate two-handed needle recapping and manual device disassembly, and instead dispose of the sharps into a puncture resistant sharps container (i.e. a safety container) immediately after use. The best practice is to discard the needle and syringe, or needle and tube holder, as a single unit, into a sharps container that is clearly visible and within arm's reach. The size of the container should permit disposal of the entire device rather than just the needle.
Proper supplies include gloves in multiple sizes, single-use disposable needles, and syringes or lancing devices in sufficient numbers to ensure that each patient has a sterile needle and collection device or equivalent for each blood sampling, as well as sufficient laboratory sample tubes to prevent reuse and manual washing.
For the majority of tests performed on serum, plasma or whole blood, a fasting specimen is preferred. Non-fasting specimens often contain fat particles that can interfere with many analytical procedures. Fasting is defined as no consumption of food or beverage, other than water, for 8 to 10 hours before testing.
PROPER IDENTIFICATION OF SPECIMENS
Specimen Labels At the time of collection, all specimens should be labeled with at least two patient identifiers.
- The patient's name (full last name, then full first name or initial) or a unique ID code is always required.
- The second patient identifier may be one of the following:
- Date of birth (month/date/year)
- Other unique patient identifier that is also on the test requisition, e.g. hospital or office ID code or file number
- Other barcode labels can be used if barcode matches the unique identifiers on the printed requisition (the barcode does not need to be human readable)
- NOTE: Location-based identifiers are NOT acceptable, e.g. hospital room number or street address
- Each specimen must have a securely affixed label with the following information:
- the patient's name written exactly as it appears on the test requisition (e.g., Doe, Jane)
- A second patient identifier as noted above
- Date of collection
If the label is hand-written, use a ballpoint pen–do not use a felt tip pen. If glass slides are submitted, use a pencil for labeling the frosted end–two identifiers are preferred although patient's name alone is acceptable.
When submitting a specimen in a container other than the tube used to draw the sample (e.g., transfer vials), also indicate specimen type on the label (e.g., serum, plasma, urine, etc.). When submitting specimens for microbiological testing (e.g., cultures, bacterial antigen, microscopic examination), the nature and anatomic source of the sample and the specific organism(s) to be detected, if any, should be specified.
PROCEDURE FOR DRAWING BLOOD
Step 1 – Assemble equipment
Collect all the equipment needed for the procedure and place it within safe and easy reach on a tray or trolley, ensuring that all the items are clearly visible.
The equipment required includes:
- a supply of laboratory sample tubes, which should be stored dry and upright in a rack; blood can be collected in:
- sterile glass or plastic tubes with rubber caps (the choice of tube will depend on what is agreed with the laboratory);
- vacuum-extraction blood tubes; or
- glass tubes with screw caps;
- a sterile glass or bleeding pack (collapsible) if large quantities of blood are to be collected;
- well-fitting, non-sterile gloves;
- an assortment of blood-sampling devices (safety-engineered devices or needles and syringes, see below), of different sizes;
- a tourniquet;
- alcohol hand rub;
- 70% alcohol swabs for skin disinfection;
- gauze or cotton-wool ball to be applied over puncture site;
- laboratory specimen labels;
- writing equipment;
- laboratory forms;
- leak-proof transportation bags and containers;
- a puncture-resistant sharps container.
Ensure that the rack containing the sample tubes is close to you, the health worker, but away from the patient, to avoid it being accidentally tipped over.
Step 2 – Identify and prepare the patient
Where the patient is adult and conscious, follow the steps outlined below.
- Introduce yourself to the patient, and ask the patient to state their full name.
- Check that the laboratory form matches the patient's identity (i.e. match the patient's details with the laboratory form, to ensure accurate identification).
- Ask whether the patent has allergies, phobias or has ever fainted during previous injections or blood draws.
- If the patient is anxious or afraid, reassure the person and ask what would make them more comfortable.
- Make the patient comfortable in a supine position (if possible).
- Place a clean paper or towel under the patient's arm.
- Discuss the test to be performed and obtain verbal consent. The patient has a right to refuse a test at any time before the blood sampling, so it is important to ensure that the patient has understood the procedure.
Step 3 – Select the site
- Extend the patient's arm and inspect the antecubital fossa or forearm.
- Locate a vein of a good size that is visible, straight and clear. The median cubital vein lies between muscles and is usually the most easy to puncture. Under the basilic vein runs an artery and a nerve, so puncturing here runs the risk of damaging the nerve or artery and is usually more painful. DO NOT insert the needle where veins are diverting, because this increases the chance of a haematoma.
- The vein should be visible without applying the tourniquet. Locating the vein will help in determining the correct size of needle.
- Apply the tourniquet about 4–5 finger widths above the venepuncture site and re-examine the vein.
Step 4 – Perform hand hygiene and put on gloves
Perform hand hygiene; that is
- Wash hands with soap and water, and dry with single-use towels; or
- If hands are not visibly contaminated, clean with alcohol rub – use 3 ml of alcohol rub on the palm of the hand, and rub it into fingertips, back of hands and all over the hands until dry.
- After performing hand hygiene, put on well-fitting, non-sterile gloves.
Step 5 – Disinfect the entry site
- Unless drawing blood cultures, or prepping for a blood collection, clean the site with a 70% alcohol swab for 30 seconds and allow to dry completely (30 seconds)
- Apply firm but gentle pressure. Start from the center of the venepuncture site and work downward and outwards to cover an area of 2 cm or more.
- Allow the area to dry. Failure to allow enough contact time increases the risk of contamination.
- DO NOT touch the cleaned site; in particular, DO NOT place a finger over the vein to guide the shaft of the exposed needle. It the site is touched, repeat the disinfection.
Step 6 – Take blood
Perform venepuncture as follows:
- Anchor the vein by holding the patient's arm and placing a thumb BELOW the venepuncture site.
- Ask the patient to form a fist so the veins are more prominent.
- Enter the vein swiftly at a 30 degree angle or less, and continue to introduce the needle along the vein at the easiest angle of entry.
- Once sufficient blood has been collected, release the tourniquet BEFORE withdrawing the needle. Some guidelines suggest removing the tourniquet as soon as blood flow is established, and always before it has been in place for two minutes or more.
- Withdraw the needle gently and apply gentle pressure to the site with a clean gauze or dry cotton-wool ball. Ask the patient to hold the gauze or cotton wool in place, with the arm extended and raised. Ask the patient NOT to bend the arm, because doing so causes a hematoma.
Step 7 – Fill the laboratory sample tubes
- When obtaining multiple tubes of blood, use evacuated tubes with a needle and tube holder. This system allows the tubes to be filled directly. If this system is not available, use a syringe or winged needle set instead.
- If a syringe or winged needle set is used, best practice is to place the tube into a rack before filling the tube. To prevent needle-sticks, use one hand to fill the tube or use a needle shield between the needle and the hand holding the tube.
- Pierce the stopper on the tube with the needle directly above the tube using slow, steady pressure. Do not press the syringe plunger because additional pressure increases the risk of hemolysis.
- Where possible, keep the tubes in a rack and move the rack towards you. Inject downwards into the appropriate colored stopper. DO NOT remove the stopper because it will release the vacuum.
- If the sample tube does not have a rubber stopper, inject extremely slowly into the tube as minimizing the pressure and velocity used to transfer the specimen reduces the risk of hemolysis. DO NOT recap and remove the needle.
- Before dispatch, invert the tubes containing additives for the required number of times (as specified by the local laboratory).
Step 8 – Draw samples in the correct order
Draw blood collection tubes in the correct order, to avoid cross-contamination of additives between tubes. As color-coding and tube additives may vary, verify recommendations with local laboratories. For illustration purposes, Table 2.3 shows the revised, simplified recommended order of draw for vacuum tubes or syringe and needle, based on United States National Committee Clinical Laboratory Standards consensus in 2003.
Step 9 – Clean contaminated surfaces and complete patient procedure
- Discard the used needle and syringe or blood sampling device into a puncture-resistant sharps container.
- Check the label and forms for accuracy. The label should be clearly written with the information required by the laboratory, which is typically the patient's first and last names, file number, date of birth, and the date and time when the blood was taken.
- Discard used items into the appropriate category of waste. Items used for phlebotomy that would not release a drop of blood if squeezed (e.g. gloves) may be discarded in the general waste, unless local regulations state otherwise.
- Perform hand hygiene again, as described above.
- Recheck the labels on the tubes and the forms before dispatch.
- Inform the patient when the procedure is over.
- Ask the patient or donor how they are feeling. Check the insertion site to verify that it is not bleeding, then thank the patient and say something reassuring and encouraging before the person leaves.
Step 10 – Prepare samples for transportation
- Pack laboratory samples safely in a plastic leak-proof bag with an outside compartment for the laboratory request form. Placing the requisition on the outside helps avoid contamination.
- If there are multiple tubes, place them in a rack or padded holder to avoid breakage during transportation.
Step 11 – Clean up spills of blood or body fluids
- If blood spillage has occurred (e.g. because of a laboratory sample breaking in the phlebotomy area or during transportation, or excessive bleeding during the procedure), clean it up. An example of a safe procedure is given below.
- Put on gloves and a gown or apron if contamination or bleaching of a uniform is likely in a large spill.
- Mop up liquid from large spills using paper towels, and place them into the infectious waste.
- Remove as much blood as possible with wet cloths before disinfecting.
- Assess the surface to see whether it will be damaged by a bleach and water solution.
- For cement, metal and other surfaces that can tolerate a stronger bleach solution, flood the area with an approximately 5000 parts per million (ppm) solution of sodium hypochlorite (1:10 dilution of a 5.25% chlorine bleach to water). This is the preferred concentration for large spills. Leave the area wet for 10 minutes.
- For surfaces that may be corroded or discolored by a strong bleach, clean carefully to remove all visible stains. Make a weaker solution and leave it in contact for a longer period of time. For example, an approximately 525 ppm solution (1:100 dilution of 5.25% bleach) is effective.
- Prepare bleach solution fresh daily and keep it in a closed container because it degrades over time and in contact with the sun.
- If a person was exposed to blood through non-intact skin, mucous membranes or a puncture wound, complete an incident report, as described in WHO best practices for injections and related procedures toolkit. For transportation of blood samples outside a hospital, equip the transportation vehicle with a blood spillage kit.
PREVENTION AND MANAGEMENT OF INCIDENTS AND ADVERSE EVENTS
Infection control procedures that help to prevent health-care associated infections include:
- hand hygiene;
- glove use;
- skin antisepsis;
- sterile, single-use blood-sampling devices;
- sharps containers;
- disinfection of surfaces and chairs;
- cleaning and disinfection of tourniquets;
- transportation of laboratory samples in labeled, washable containers.