Specimen Collection - Arterial Blood Gas

The primary responsibility of a phlebotomist is to collect blood for laboratory analysis, which is necessary for diagnosis and care of the patient. Collection of a quality specimen is the first step in providing an accurate test result.

Equipment for blood collection:

Blood collection equipment is located in the Phlebotomy area. Additional supplies may be stored in other locations due to space constraints. Phlebotomy tray must be kept clean and neat. Sharps containers are provided for use on phlebotomy trays and must be used to dispose of sharps if a wall mounted sharps container is not readily available.

A. Collection Equipment required when using winged infusion Safety Lock Vacutainer Blood Collection Set (Butterfly). 

1. Equipment specific for using Vacutainer tube with winged infusion set.

a. Safety Lock Vacutainer Blood Collection Set with 12-inch tubing and multisample luer adapter. The most commonly used is the 21g or 23g 3/4 inch set. A 25g ¾ inch set is available for pediatric and special needs patients.

b. Disposable vacutainer holder or blood culture collection BactiAlert adapter cap and adapter insert.

2. Equipment specific for using syringe with winged infusion set.

a.  Safety Lock Vacutainer Blood Collection Set with 12-inch tubing and multisample luer adapter. The most commonly used is the 21 g or 23g 3/4inch set. A 25g ¾ inch set is available for pediatric and special needs patients.

b.  3 cc, 5 cc or 10 cc sterile syringe.

3. Equipment to be used with all methods of collection by winged infusion set.

a.Vacutainer collection tubes or blood culture collection bottles.

b. Venipuncture site cleaner: 70% isopropyl alcohol pads for standard procedures and iodine sepps 2% for blood cultures.

c. Medical tape.

d. 2x2 gauze pads.

e. Tourniquet.

B. Collection equipment when using Vacutainer evacuated tube system with vacutainer safety needle and disposable vacutainer holder.

1. Equipment required when using Vacutainer evacuated tubes, vacutainer safety needle and disposable holder.

a. Vacutainer safety needle, 21 or 22 gauge.

b. Disposble vacutainer holder or blood culture collection BactiAlert adapter cap and adapter insert.

c. Vacutainer collection tubes. Blood cultures direct inoculation into specimen bottles must not be collected by this method, however blood culture collection into Vacutainer tube with SPS additive may be collected by this method.

d. Venipuncture site cleaner: 70% isopropyl alcohol pads for standard procedures and iodine sepps 2% for blood cultures.

e. Medical tape.

f. 2x2 gauze pads.

g. Tourniquet.

C. Collection equipment using syringe with hypodermic needle to fill Vacutainer tubes.

1. Hypodermic, eclipse safety 21g or 22g needles.

2.  3 cc, 5cc or 10 cc single use sterile syringe.

3. Vacutainer collection tubes or blood culture collection bottles.

4. Venipuncture site cleaner: 70% isopropyl alcohol pads for standard procedures and/or iodine sepps 2% for blood cultures.

5. Medical tape.

6. 2x2 gauze pads.

7. Tourniquet.

D. Collection equipment when collection is performed by skin puncture.

1. Lancet specific to depth of puncture needed and volume of specimen required.

a. Lancet for preemies 0.85mm depth.

b. Lancet 1.25mm pediatric patients (up to one year).

c. 1.75mm for general use on adults, larger children and when larger volumes are required for children over one year of age.

2. Microtainer collection tubes.

3. Infant heel warmer or other warming equipment such as wash cloth or towel that can be moistened with warm (not hot) water.

4. Skin puncture site cleaner: 70% isopropyl alcohol pads.

5. Medical tape.

6. 2x2 gauze pads.

7. Band-Aid (optional).

Preparing for the venipuncture or skin puncture:

A. Always wear gloves and impervious lab coat when performing blood collection, handling blood specimens or when in an area where surface(s) may be contaminated. If special isolation precautions are posted on patient door then lab coat must be removed outside patient door and appropriate isolation protective equipment provided used while in the room.

B. When entering the patient's room knock lightly on door and open door slowly.

C. Approach the patient professionally. Say good morning, address patient by name, identify yourself and state why you are there (example: Good morning Mr. Smith I am from the Laboratory and I am here to collect a blood specimen that your physician has ordered.

1. If the patient is asleep gently attempt to wake patient.

2. If patient appears to be in distress notify nurse immediately.

3. If patient is unconscious talk to patient as if he/she were awake.

4. If family or doctor is with patient inquire if you should proceed to next patient and then return.

5. If patient is not available contact patient's nurse to determine when patient will return, document reason for rescheduling, along with nurse's name and send to lab to be rescheduled in computer.

D. Patient must be comfortably positioned with adequate support for extremity during the procedure.

E. Put on a new pair of gloves at patient bedside pulling glove over cuff of lab coat.

F. Follow procedure for proper patient identification.

1. Inpatient identification-check requisition and armband to make sure patient name and medical record number match. If patient is awake, alert and reliable ask patient his/her name.

2. Outpatient without armband must be asked to state full name and identifying number such as social security number and birth date. Patient should be asked to state name again at end of procedure.

G. If patient objects or refuses and it is determined by the Phlebotomist that the patient truly will not allow the procedure (after some gentle persuasion) the phlebotomist must notify the patient's nurse, document refusal, document nurses name and time of notification on the requisition label and return requisition to the lab for cancellation or rescheduling per nurse or physician instructions.

H. Verify special restrictions or patient preparation for the procedure has been met. For example, if you are to collect a fasting glucose determine if the patient is fasting, or for drug levels is it the proper time for collection in relation to dose?

I. Review test requisitions (labels) to determine all specimens needed.

J. Lower bed rail, raise bed, turn on lights pull curtain or make other adjustments necessary for completing procedure and/or ensuring patient comfort and privacy during procedure.

K. Proceed with collection.

Collection of specimens:

Only one phlebotomist should enter patient room, or approach patient, unless the second phlebotomist is there as part of a training program, competency assessment, inspection or the patient has special requirements needing two persons to collect specimen. Phlebotomist should explain why two persons are there and always talk to and with the patient in a calming, quite tone. The two phlebotomists should not hold any discussion other than procedure related instructions and information relevant to that specific patient. You are the LABORATORY to these patients.

Performing venipuncture on children under one year of age presents special challenges and requires expertise and skills unique to the pediatric population. Venous collections on children under one year of age will be performed by nursing staff in Pediatrics, NICU or Nursery. If an outpatient under one year of age presents to an outpatient location, skilled staff in that area will be responsible for collection. If skilled staff is not available in outpatient location nursing from one of the inpatient departments previously listed will be called to perform collection. Heel sticks or other skin punctures on children under one year of age may be done by laboratory or nursing personnel qualified to do procedure.

Special needs and considerations of Geriatric and Neonatal patients as well as patients with medical conditions that may affect "normal" physical or mental states must be taken into consideration by the Phlebotomist while performing specimen collection.

Specimen requirement for each test is shown on printed requisition label and may be found in Flexilab function MIQ and in the Online Laboratory Manual.

A. Venipuncture Procedure for use with winged infusion Safety Lock Vacutainer Blood Collection Set, Vacutainer evacuated tube system or syringe method.

1. Gather needed supplies to include tourniquet, 70% isopropyl alcohol pad, 2% iodine sepps, vacutainer tubes needed for tests ordered, dry gauze pads and medical tape. Vacutainer tubes needed may be determined by information on printed collection labels, in Flexilab function MIQ or the Online Laboratory Manual.

2. Put on clean close fitting gloves and pull glove over cuff of lab coat.

3. Locate appropriate venipuncture site by palpating the vein with the tip of the index finger. This may be aided by applying tourniquet and/or asking the patient to close his/her hand so veins become more prominent. Do not allow patient to vigorously pump hand. Do not leave tourniquet on more than one minute or hemoconcentration may result and test values may be affected. Tourniquet should be released and applied again just prior to venipuncture procedure.

a. Considerations for selection of venipuncture site:

1. Do not place a tourniquet or stick above or close to an IV site currently being used.

2. Do not collect from a line, catheter or heparin well or perform arterial stick. These samples will be collected by staff specifically trained for these collections.

3. Ask patient or look for posted instructions specifying where patient should not have procedure performed or other special instructions. These instructions should be posted on the wall near the head of the bed.

4. Do not perform venipuncture from side on which a mastectomy was performed within the last 6 months.

5. Do not collect blood from an extremity that has had a joint replacement.

6. Do not perform venipunture above or near a heparin well without obtaining permission from patient's nurse. If collecting near a heparin well make sure all potential heparin infusion is discontinued for a minimum of 10 minutes before collection.

7. If a venipuncture site cannot be located in the arm or hand then perform a fingerstick if specimen needed (type and volume) allows for this procedure.

8. If a venipuncture site is not available and a finger stick is not possible then notify the nurse and ask him/her to obtain orders for a foot stick or arterial stick.

9. Avoid burned, scarred, tattooed or cut down areas.

10. Look carefully for damaged veins. If the vein is hard and lacks resiliency, vein must not be used.

11. Avoid localized edematous areas or area of hematoma.

12. Do not perform venipuncture on any extremity other than arm without a physicians written order or that procedure. 

4. Clean venipuncture site with 70 % isopropyl alcohol pad using a circular motion starting in the center and moving in concentric circles away from the center of the venipuncture site. Allow site to air dry.

5. Remove sheath from needle and visually inspect needle for hooks, spurs or other defects.

6. Anchor the vein by pulling the skin tight one to two inches above and/or below venipuncture site with thumb or thumb and finger of non-dominant hand. This anchors the vein to help keep it from moving or rolling upon needle entry.

7. Warn the patient of needle insertion by stating "You will feel a stick". Insert needle into vein with bevel up at a 15 to 30 degree angle.

8. Fill tubes in correct order of draw. Fill to required volume or full volume, invert tube and place on ice or keep warm if required by test (specific test requirements are printed on collection label and can be found in the Online Laboratory Manual).

a. Order of draw (see Vacutainer Tubes - Order of Draw for graphical representation) 

1. Tube for metals (no additive)

2. Blood culture bottles (one set is 1 pediatric or 1 purple top and one blue top bottle or 1 green top bottle and one purple top bottle depending if patient is on antibiotics). Blood culture sps additive tubes if tubes are being used in lieu of bottles.

3. Red top tube with no additive.

4. Other no additive tubes.

5. Blue top coagulation tubes.

a. Blue top tubes for PT or PTT or other Coagulation tests must be filled to blue line or other indicator line. Failure to fill completely will affect test results and cause specimen to be rejected. Invert 10 times to mix and avoid clotting.

b. Fibrin split tubes must not be overfilled and should clot immediately.

6. Green top tubes, invert as required by test.

7. Purple top tubes.

a. invert 10 times to mix specimen and decrease chance of clotting.

b. Blood Bank and Hematology require separate tubes.

8. Yellow top gel tubes, invert as required by test.

9. Gray top tubes, invert 10 times to mix.

10. Other additive tubes, invert 10 times to mix.

9. If blood does not enter tube try repositioning the needle in the vein, reposition the needle in relation to the vein (too deep or shallow), trying another tube in the event that vacuum seal had been compromised on first tube. If specimen is not obtained in two attempts the phlebotomist will find another phlebotomist to assist with collection.

10. When using syringe method attach syringe to infusion set, or needle. Syringe method should be used only if patient has weak or fragile veins that collapse easily. Small volume vacutainers are preferable to syringes due to specimen integrity and safety for the phlebotomist.

a. Check syringe for free movement of plunger before using.

b. Syringe allows phlebotomist to control pressure but there is a higher risk of specimen clotting. Phlebotomist should pull back slowly on the plunger and allow barrel to fill slowly. Too much pressure can cause hemolysis of specimen or collapse of vein of patient.

c. When filling the vacutainer evacuated tubes

1. Fill in same order as order of draw above.

2. Penetrate stopper and allow vacuum to fill tube. Do not force blood into tube by pushing on plunger.

3. To minimize chance of hemolysis slant needle to side of tube so that blood runs down side of tube.

4. To avoid needle sticks, place tubes in rack to fill. Do not hold tubes in hand while filling.

5. Dispose of needle and syringe as one unit in wall mounted sharps container. Do not recap or remove needle.

11. Collection of blood cultures by direct inoculation into blood culture bottlemust be done using winged infusion set. Make sure bottle is below venipuncture site to avoid infusion of media into patient. Collection of blood culture specimens into vacutainer tubes may be done with standard evacuated tube set or syringe.

a. Remove sterile lid and clean top of blood culture bottle or tube with 70% isopropyl alcohol and allow to air dry before using.

b. Clean skin over venipuncture site using 70% isopropyl alcohol for 30 seconds and allow to air dry for 10 seconds.

c. Clean skin over venipuncture site a second time using iodine sepps 2% beginning in the center and proceeding in circular motion to outer edge of site.

d. Remove iodine from site with a second application of alcohol and allow to air dry (optional or use if patient is mildly sensitive to iodine).

e. For patients hypersensitive to iodine use a double application of 70% isopropyl alcohol and allow each application to dry thoroughly.

f. Guidelines for volume of blood collected per culture:

1. 0 to 6 months one pediatric collection bottle with 0.5 to 2.0 mls.

2. 6 months to 5 years one pediatric bottle with 2.0 mls or one adult collection set with 2.5 mls per bottle (see weight chart attached).

3. 6 years and over adult collection set with 5.0 to 10.0 mls per bottle (see weight chart attached).

12. If blood cultures times two are ordered collect second set from another site.

13. Collect other lab work ordered. If necessary use bacti-alert adapter insert.

14. When last tube has been filled remove it from the vacutainer holder.

15. Fold a clean gauze square into fourths and place over the site where the needle enters the vein. Do not press but hold lightly in place until needle is removed.

16. Withdraw needle in one smooth motion and immediately apply pressure to the site with the gauze pad. It is acceptable to ask patient to apply pressure to the gauze pad/venipuncture site if he/she is alert, willing to assist and capable of participating in the procedure.

17. Activate safety sheath over needle and dispose of needle and needle holder immediately by placing it in a sharps container. Do not recap, bend, break or remove needle from holder. Never stick needle into patient's mattress. Do not leave unsheathed needle on bed, table or other area. Dispose of collection set as quickly as possible.

18. Before leaving the patients room check the venipuncture site to be sure bleeding has stopped. When coagulation test(s) it is anticipated that bleeding will be heavier and more prolonged than in normal patients. Pressure may need to be applied for a longer period of time and checked more than once before leaving the patient.

B. Skin puncture procedure.

Blood obtained through skin puncture is a mixture of arterial blood, venous blood and capillary blood along with interstitial and intracellular fluids from surrounding tissues. Composition of skin puncture blood will differ from venous blood and normal values for certain tests may be different.

If blood specimen is submitted in a Microtainer specimen tube it must be a skin puncture specimen unless other wise clearly noted on the specimen container.

Some tests cannot be performed on skin puncture specimen. This includes sedimentation rate, coagulation studies, blood cultures, some reference lab tests and any test requiring a large volume.

1. Gather needed supplies to include, lancet, warming device, 70% isopropyl alcohol pad, microtainer tubes needed for all tests ordered and dry gauze pads and tape or Band-Aid. Microtainer tubes needed may be determined by information on printed on collection labels, in Flexilab function MIQ or from Online Laboratory Manual.

2. Put on clean close fitting gloves and pull glove over cuff of lab coat.

3. Select skin puncture site.

a. Skin puncture site should be warm, pink, and free of scars, cuts, bruises or rashes.

b. Finger stick should be made on the end segment of the middle or ring finger of the non-dominant hand. Puncture should be made slightly to the side of center and perpendicular to the whorls of the fingerprint, do not puncture parallel to the grooves of the fingerprint. Do not puncture side or very tip of finger. Do not perform finger stick on infant, small children or on finger with little tissue between skin surface and bone.

c. Heel stick must be performed on infant or small children. Heel puncture must be performed only on the plantar surface of the heel, medial to an imaginary line drawn from between the fourth and fifth toes to the heel and from the middle of the great toe to the heel (see attached diagram). Puncture should be made perpendicular to the lines of the footprint.

4. Warm puncture site if needed.

5. Clean puncture site. Use 70% isopropyl alcohol do not use iodine to clean skin puncture sites. Allow alcohol to dry completely. Alcohol not completely dry and iodine will interfere with testing and/or cause hemolysis.

6. To perform a finger stick or heel stick:

a. support patient's arm on firm surface. Place infant for heel stick in secure position on surface where procedure is being performed.

b. For finger stick grasp finger firmly between thumb and index finger and perform puncture.

c. For heel stick grasp heel firmly, but gently, with index finger supporting the arch and the thumb wrapped around the ankle and below the puncture site.

d. Dispose of puncture device in sharps container.

e. Wipe away first drop of blood with clean dry gauze.

f. Position the site downward and apply moderate pressure to site. Do not squeeze or massage site vigorously.

g. Proceed to collect specimen using by touching the collection tube "scoop" to the drop of blood and let the drop of blood run down the wall of the tube. Tap the tube gently to settle specimen to bottom of the tube and mix with tube additive if necessary. Do not scrape scoop against the skin.

h. When collection is completed, cap tube and invert 8 to 10 times gently tapping if necessary for complete mixing.

i. Elevate site and apply gentle pressure with a clean gauze until bleeding stops.

j. Apply small bandage to adults and large children if desired. Do not apply bandage to infants or young children (under 2 years of age).

Failure to collect specimen.

A. After two unsuccessful attempts at collection the phlebotomist will find another phlebotomist to assist with collection.

B. Phlebotomist must notify the patient's nurse of the missed collection and document name of person and time notified on collection label or requisition.

C. Do not leave collection label in room or at Nursing Unit. Label must be given to phlebotomy clerk to document the miss in the computer and to the phlebotomist assisting with collection of the specimen.

Completion of Specimen Collection (Labeling and Transport)

A. Label specimen at the bedside with an indelible pen. Minimum information required on the label:

1. Patient's name. Blood Bank specimens must have full name.

2. Patient's medical record number.

3. Date, time and initials and/or tech code of person collecting specimen.

B. Attach label firmly to specimen container This is very important. If label comes off specimen is not acceptable and if bar code is not properly positioned instrument will not be able to read bar code and testing may be delayed.

C. Observe any special handling procedures such as keeping warm, keeping on ice or protecting from light.

D. Check specimen label with armband or other patient identification information.

E. Place specimen in biohazrd bag for transport on phlebotomy tray to receiving site or transport site.

F. Check venipuncture or skin puncture site to see if bleeding has stopped. Once bleeding has stopped apply bandage over site.

G. Dispose of contaminated material in proper biohazard containers.

H. Make sure bed rails are up if you have lowered the rails, replace patient table in position as you found it or as patient requests, lights are on or off as you found them (unless patient request differs) and door is in the position it was in when you arrived. Leave room quietly.

I. Do not leave materials or trash in patient room unless it is disposed of in a proper trash receptacle.

J. Thank the patient, family, visitor, and/or caregiver for his/her cooperation. Please leave the patient with a positive feeling about the procedure and the Laboratory.

K. Remove gloves and wash hands.

L. If patient had any requests Phlebotomist will contact patient's nurse and communicate the patient's request.

M. Receive specimen in Flexilab computer, or send to Phlebotomy/Laboratory to be received in computer or record collection on manual requisition.

N. Specimens may be double bagged in sealed biohazard bags and transported through pneumatic tube system or in case of pneumatic tube down time transport manually to specified location.

O. Transport specimen to central processing in Zimmer building as quickly as possible.