Skin puncture blood is a mixture of blood from arterioles, venules and capillaries. Capillary skin punctures are useful in pediatric patients since small but adequate amounts of blood for most laboratory tests can be obtained. It is also useful in some adult patients if venous samples are unobtainable.
The BD Lancet is contact activated and assures incisions of uniform depth.
Note: In determining the capillary blood collection method for small children, factors such as the size of the child, the existence of lesions at the anatomic collection site, the nature of the tests that have been ordered, etc., all need to be weighed by the phlebotomist. Guidelines to which we typically conform are:
In children 9 months or less, heelstick is recommended.
In toddlers and children 10 months to 2 years of age a fingerstick is performed.
II. Clinical Significance: N.A.
1. Capillary blood collected into the appropriate collection container for testing. (Refer to specific analytic procedures.)
2. Specimen integrity:
A. A free flow of blood is essential to obtain reproducible results that are comparable to results received on venous specimens.
B. The specimen must be free of tissue fluids and hemolysis.
1. Approved gloves, labcoat and safety glasses (In accordance with the “Personal Protective Equipment” (PPE) section of the UCL Exposure Control Plan.)
2. BD Microtainer Contact-Activated Lancet (blue), 1.5 mm (Fisher #02-657-102)
3. 70% alcohol wipes (CardinalHealth #KC5150A)
4. 2 x 2 gauze squares (Fisher #KC2252)
5. Heel warmer (Fisher #22024647)
6. Refer to “Microtainer Blood Collection System” procedure for acceptable micro collection containers.
V. Reagents: N.A.
VI. Standardization: N.A.
2. Hands are washed before having direct contact with the patient. Hands are washed after removing gloves. Refer to “Handwashing” within the Engineering Work Practice Controls section of the Exposure Control Plan.
3. The minimum PPE required to perform this procedure is designated labcoat, safety glasses and gloves. Put fresh gloves on, in view of the patient (and/or parents) and prior to touching the patient.
4. Choose either the long (middle) or ring finger making sure that it is free of local circulatory changes (pallor, cyanosis, edema or inflammation).
Note: The middle and ring fingers are preferred. Never use the 5th finger.
5. If the fingers are cold, warm the hand a few minutes with a warm, moist towel that is comfortable to the touch, or a heel warmer. Warming increases blood flow.
6. Clean the puncture site using a 70% alcohol wipe. Wipe the site dry with clean gauze before performing the puncture.
Warning: Do not use Betadine since it can falsely elevate some tests.
7. Twist off the blue protective tab.
8. Grasp prepared finger firmly to prevent sudden movement. Select an incision site. The site should be off center, in the upper portion of the finger cutting across the fingerprint lines. DO NOT USE TIP OR SIDES OF FINGER. (Refer to diagram.) Place the lancet surface against the finger and push down on the device to activate. The lancet automatically retracts in the device.
9. After triggering, immediately remove the device from the finger.
10. Wipe away the first drop of blood using clean, dry gauze.
Note: The only exception to this is with capillary specimen collection for the POCT CoaguChek analyzer. The first drop of blood is NOT wiped away for the POCT CoaguChek capillary specimen collection. The first drop of blood is used for the analysis.
The blood will well up into a large rounded drop and flow freely without squeezing. The blood flow from the puncture is enhanced by holding the finger downward and gently applying continuous pressure to the surrounding tissue proximal to puncture site. Do not milk the finger.
11. Proceed to collect blood in tubes appropriate for the tests that are to be performed. (See individual test procedures.) Collect the CBC and/or platelet tubes first, when a number of tests are ordered, to minimize the effects of platelet aggregation at the puncture site.
12. Apply pressure and elevate the hand until bleeding has stopped. Band-Aids are not recommended for use on small children.
13. Seal and label the specimen(s) as per laboratory protocol.
14. Dispose of the Lancet in an approved sharps container.
15. Remove gloves and wash hands. If gloves have not been visibly contaminated with blood and/or body fluids, hands may be washed using an approved hand sanitizer. If during the blood collection procedure gloves have become visibly contaminated with blood or body fluids, hands are washed using soap and water.
16. Except for specimen acquisition in some Point of Care (bedside) testing:
A. Indicate "fingerstick" on the requisition and if prewarmed. (PW denotes pre-warmed.) The following abbreviations are used to describe the location of the fingerstick:
a. R denotes Right
b. L denotes Left
c. M denotes Middle Finger
d. RF denotes Ring Finger
Example: If a fingerstick is performed on the left hand using the middle finger: "Fingerstick LM" is indicated on the requisition.
B. Deliver the specimen to the laboratory as soon as possible. Register the sample upon arrival.
VIII. Limitations: N.A.
IX. Results Derivation: N.A.
X. Expected Result(s) and/or Critical Values: N.A.
XI. Quality Control: N.A.
1. Bruck, Erika, M.D.; NCCL, Vol. 11, 3rd Edition, "Procedure for the Collection of Diagnostic Blood Specimens by Skin Puncture", July 1991.
2. College of American Pathologists; "So You're Going to Collect a Blood Specimen, 4th Ed., 1989.
3. Phelan, Susan, MHS MT(ASCP); "Blood Collection - The Pediatric Patient" American Society of Clinical Pathology Press, 1990.
4. Morbidity and Mortality Weekly Report, Vol:51, No. RR-16, pp 1-44, October 25, 2002.
5. bd.com website.
i. August 1986 L. Johnson
ii. 4-12-92 A. Bergman
iii. 11/18/94 S. Raymond, Lynn McGovern (Tenderlett, POC, IV, I)
iv. January 2002 L. McGovern (Revised: VII.10.note added)
v. April 2011 R. Schaefer (Revised: for BD lancet)
December 2009 R. Schaefer (Revised: removed lists of trained staff)
December 2010 T. Gee (Revised: I.; III.2.B.; IV.6.)
March 2011 L. McGovern (Revised: IV.6.)
December 2011 T. Pfeiler (Revised: IV.p/n’s, 5 added; VII.5., 16.B.)
April 2012 J. Powers (Revised: VII.7., 16.B.)