BLOOD COLLECTION

Effective Date: 
Tue, 05/01/2012
Reviewed: 
Tue, 01/10/2017
Policy: 

PURPOSE

The safety of both the patient and the phlebotomist must be considered during the process of blood collection. The objective is to obtain the best possible sample for the test to be performed. Only trained certified and licensed personnel working under the direction of a qualified, licensed physician may procure blood. The phlebotomist must adhere to the policies set forth by the facility, because those policies were developed to protect both the patient and the phlebotomist.

SPECIMEN

The laboratory staff is permitted to collect blood from two sources only: capillary (peripheral) and venous blood. Arterial blood may be used in certain testing situations, but such blood must be collected only by physicians or by staff with documented training in the collection of arterial blood specimens. The laboratory staff should not withdraw blood from a Hickman catheter (or other central line), as this requires the introduction of drugs, saline, or heparin; this procedure can only be performed by licensed personnel such as physicians or registered nurses. The phlebotomist must be suitably familiar with the laboratory tests so that the proper amount of blood is collected, is placed in the correct test tubes, and is processed according to the protocol of the specific test methodology.

REAGENTS AND MATERIALS

70% isopropyl alcohol (pre-packaged alcohol wipes)

Gauze sponges or cotton balls

Assorted needles, sterile, single use: 18-23 gauge, 3/4" to 1/2” length

Multi-draw needles for use with evacuated collection tubes

Or Hypodermic for use with a syringe

Or Butterfly tubing for use with a syringe and/ or evacuated tubes

Or Lancets, sterile, single use for collection of capillary blood

Multi-draw needle holder

Disposable gloves

Tourniquet

Sharps disposal container for contaminated needles, lancets, syringes, test tubes

Appropriate selection of evacuated collection tubes for blood processing

Adhesive bandages

Soap, water, paper towels or antimicrobial foams or gels for hand cleansing

Procedure: 

(Universal Precautions must be maintained at all times: See Exposure Control Plan for Blood-Borne Pathogens)

It is imperative that the patient, whether sitting or reclining, be made as comfortable as possible. Psychological comfort may also be required, so take time to explain the procedure to the patient.

Always wear gloves, throughout the entire procedure, when obtaining blood specimens.

VENOUS COLLECTION

Securely fasten a tourniquet around the patient’s arm, just above the elbow. Instruct the patient to keep his arm as straight as possible and to make a fist (if possible). Gently palpate the antecubital area in search of a suitable vein. It may be necessary to examine the other arm, wrists, or hands.

When a vein has been located, thoroughly cleanse the site with disinfectant. Allow to dry.

Assemble the vacuum collection set of syringe and needle. Remove the needle cap or sheath.

Grasp the patient’s arm (or hand) with your free hand to hold the skin and underlying tissue taut.

Insert the needle into the vein by using a quick, deliberate motion. Begin to withdraw the blood by (a.) inserting the vacuum tube(s) onto the sheathed end of the multi-draw needle, or by pulling back on the syringe plunger. If blood does not return, it may be necessary to make small adjustments to the position of the needle to penetrate the vein.

NOTE: Do not or try to make large adjustments; this action will only cause discomfort to the patient and may even bruise the area. If you are unsuccessful in obtaining a good blood flow, retract the needle, and apply a gauze sponge or cotton ball to the area with pressure until bleeding stops. It may be necessary to select a second area to try again. If after two tries, you are unsuccessful, ask a co-worker to make an attempt.

When sufficient blood has been withdrawn, release the tourniquet. Place the clean gauze sponge or cotton ball over the puncture site. Simultaneously withdraw the needle while using the sponge to apply pressure to the site.

Instruct the patient to apply pressure to the puncture site with the other hand. If the patient is unable, you should continue to apply pressure to the site until bleeding has stopped.

Failure to apply adequate pressure can result in a hematoma, or bruise, to the draw site.

Order of Draw:

If you are using a Multi—draw needle for multiple tube collections, insert the tubes into the needle holder in this order:

  1. Blood Culture (or “Sterile tubes")
  2. Citrate tube (light blue top)
  3. Serum tube ("red top"), or Gel separator (brown "tiger top")
  4. Heparin tube (“green top") or Gel separator with Heparin (green “tiger top")
  5. EDTA tube (“purple or lavender top")
  6. Fluoride tube (“gray top”)

If using a syringe, dispense blood into appropriate tubes as soon as possible after drawing, by inserting the needle through each tube’s stopper.

Take care not to stick yourself.

After blood has been dispensed into the tubes dispose of the needle apparatus into appropriate Sharps biohazard waste containers.

All tubes except plain "red top" tubes must be mixed immediately by gently inverting 8 to IO times. ALL tubes must be properly labeled immediately AFTER filling them. Take care that you have matched the specimens to the correct patient and label them:

Patient’s first and last names

Patient’s secondary identifier (Patient ID or medical record number)

Date and time of collection

Initials of phlebotomist

When the puncture site has stopped bleeding, apply an adhesive bandage, gauze or other suitable material.

Clean any blood spills with disinfectant. Remove and discard gloves. Thoroughly wash your hands with soap and water, or use an appropriate antimicrobial foam or gel for hand cleansing.

Precautions:

1. Place extra evacuated collection tubes for the procedure in a convenient place near the draw area. If the tube you are using has lost vacuum, a fresh tube may be inserted in the holder and onto the needle.

2. Use a flat rubber tourniquet rather than round tubing. Round tubing bites into the skin and causes the patient discomfort.

3. Make certain evacuated collection tube stoppers are not loosened or punctured before use. Partial or complete vacuum loss will result. If this occurs, immediately discard tube.

4. Evacuated collection tubes containing anticoagulant should be filled to capacity. It is important the blood to anticoagulant ratio be correct to avoid a greater than allowable dilution of the blood.

CAPILLARY PUNCTURE

After putting on a pair of gloves:

Decide on the site of the puncture. The most frequently chosen sites are the ring finger, or the middle finger, at the top and slightly to the side of the finger. From infancy into childhood, the choices are generally from the heel, to a toe, to a finger, as the child progresses in size. lf the chosen site is cool, it is helpful to stimulate blood flow massaging the area or wrapping it with a warm compress.

Thoroughly cleanse the site with 70% alcohol. Vigorous rubbing with the wipe may stimulate circulation in the area. Allow to air dry (do not blow on the site).

Quickly and firmly lance the tissue. The lancets are designated so that the depth of the puncture is controlled (3—4mm).

Wipe the first drop of blood away with the sponge, as it is likely to contain tissue fluid that would dilute the test results. Collect the second and following drops of blood.

Resist the temptation to squeeze the site, as this forces tissue fluid to dilute the blood.

Gently massage the area to assist the flow of blood toward the puncture site. Also, position the puncture site downward if possible to take advantage of gravitational pull.

Collect blood droplets in the appropriate capillary collection device. As each droplet is introduced, gently tap the container to move the blood to the bottom of the tube.

When sufficient sample has been collected, apply pressure to the puncture site until bleeding has stopped. Apply an adhesive bandage.

Discard the lancet and any contaminated materials in a “Sharps" disposal container.

Label all capillary blood tubes with at least the patient’s name and the date. The small size of these tubes limits the amount of information that can be included.

Clean any blood spills with disinfectant. Remove and discard gloves; thoroughly wash your hands with soap and water, or use an appropriate antimicrobial foam or gel for hand cleansing.

ANTICOAGULANTS

Most anticoagulants prevent blood clotting by removing ionic calcium from the blood with the formation of a unionized calcium salt. Heparin prevents coagulation by removing one of the clotting factors - thrombin. The anticoagulant effect of Heparin lasts approximately 24 hours.

Most chemical analyses are performed on serum. To obtain serum, the blood is allowed to clot in the absence of anticoagulant.

In the analysis of carbon dioxide or glucose, special precautions are necessary to achieve value results. The carbon dioxide determination requires that the blood remain in an anaerobic state until analysis. An anaerobic state is obtained by never allowing the blood to be exposed to air by not opening the tube until immediately before testing. Glucose is vulnerable to enzyme action resulting in a marked decerase of glucose, a process called glycolysis. Because the enzymes that cause glycolysis are in the red blood cells, separation of the red cells from the plasma or serum will reduce glycolysis. These enzymes can be inhibited by using sodium fluoride as the anti-coagulant.

Serum or plasma may be stored at room temperature, under refrigeration, or in the freezer, depending on the determination to be run. With few exceptions, the lower the temperature, the greater the stability of the constituents.

Plasma is blood minus the cellular elements (white and red blood cells and platelets); serum is plasma that has been allowed to clot; most of the coagulation factors have been activated to form the fibrin clot.

NOTES

1. lf venipuncture is not successful, another site should be chosen. Under normal circumstances, if blood cannot be obtained after two attempts, capillary collection should be considered or another staff member should attempt venipuncture.

2. Never recap needles except for special procedures, such as for blood gas collection. Refer to your facility Safety Manual for further information on the recapping of needles.

3. Use a new collection set for each attempt at venipuncture (or capillary puncture). The skin is to be cleansed with alcohol again, even if the puncture is in the same area as the first attempt. Never re-use a needle or lancet.

4. Wash your hands before touching the patient and after each collection procedure.

5. Syncope, or lightheadedness, is a common complication of blood collection. If the patient states that this often happens adjust the phlebotomy chair to have him/her in a semi-supine position before the procedure. If a patient becomes lightheaded or dizzy, or begins to faint, terminate the procedure immediately and adjust the phlebotomy chair to the full supine position. Call for assistance before moving the patient; never let the patient leave without fully recovering.

6. If any injuries occur, such as accidental needle sticks to staff or patient, or patient falls, always fill out an Incident Report and give it to the appropriate person for follow-up.