What is the order of draw for capillary blood specimens

Blood samples must be drawn by phlebotomists in a specific order to avoid cross-contamination of the sample by additives found in different collection tubes. Phlebotomy order of draw is the same for specimens collected by syringe, tube holder, or into tubes preevacuated at the time of collection. The correct order of draw follows:

1. Blood culture tube or bottle
2. Sodium citrate tube (eg, blue closure)
3. Serum tubes, including those with clot activator and gels (eg, red, red-speckled, gold closures)
4. Heparin tube with or without gel (eg, dark green, light green, speckled green closures)
5. EDTA tube with or without gel separator (eg, lavender, pearl, pink closures)
6. Sodium fluoride/potassium oxalate glycolytic inhibitor (eg, gray closure)

The placement of tubes not listed here should take into consideration the potential for their additive to alter results obtained from the next tube if carryover were to occur. Plastic serum tubes containing a clot activator may cause interference in coagulation testing. Only blood culture tubes, glass nonadditive serum tubes, or plastic serum tubes without a clot activator may be collected before the coagulation tube.

Numerous errors can occur during the collection and handling of blood specimens, which pose significant and avoidable risks to the patient and the phlebotomist. When global standards are not fully implemented, it is more likely that patients will be injured during the procedure, biologically representative specimens will not be obtained from patients, and test results will not be comparable from one facility to another.

CLSI’s GP41 —Collection of Diagnostic Venous Blood Specimens provides a descriptive, stepwise process and procedures reflecting the quality system essentials format for diagnostic venous blood specimen collection. Special considerations for collections from vascular access devices, blood culture collection, and collections in isolation environments are included, as well as how to handle emergency situations. An expanded appendix section provides helpful tips for collecting specimens from pediatric and other challenging patients.

← Go Back

Collection Procedure:

LTD: Performing a Capillary Puncture  Version 7

Performing a Capillary Puncture 

General Guidelines for a Capillary Puncture: Capillary punctures are ideal for

small children when only a small volume of blood is needed. They are also

advantageous in certain adult populations, such as: those with severe burns,

obese patients, those with thrombotic tendencies, and for point-of-care testing

when a small volume of blood is needed. Capillary puncture should not be used

on patients who are extremely dehydrated or have poor peripheral circulation.

Areas of fingers and heels that are cold, swollen, scarred or covered with a rash

should be avoided. A warm compress or heel warmer should be used to warm

fingers and heels that are cold, or if a capillary blood gas is being drawn, to

increase the circulation of blood to the area.

All approved lancets utilized at Akron Children’s are for single use and feature

automatic retraction of the blade.

Heel punctures are performed on infants less than 6 months of age, or on

older premature infants who are the approximate size of a full-term 6 month

old. For children over 6 months and adults, the finger is punctured. It may be

necessary, on occasion, to perform a capillary puncture on the toe of a patient

who is severely burned. Follow the same procedure as for performing a finger

capillary puncture.

Order of Draw for a Capillary Puncture: Proper collection of tubes when

performing a capillary puncture is as follows:

1. Gas tubes (must warm the site before collecting the specimen)

2. Slides

3. EDTA - purple top tube

4. Heparin – light or dark green top tube

5. Serum – red top or amber tube with red top

Procedure for Capillary Puncture of the Finger:

 The best site for a finger puncture is just off the center of the finger pad of

the 3rd (middle) or 4th (ring) finger of the hand. The sides and the tip of the

finger should be avoided.

 Select the proper approved lancet: The BD Microtainer Contact-Activated

Lancet 1.5 mm (lavender) is used for glucometers and the BD Microtainer

Contact-Activated Lancet 2.0 mm (blue) is used any time you need more

than a drop or two of blood.

 Prepare the finger by cleaning it with a Chlorhexadine wipe. Allow it to air

dry.

 Grasp the finger, and using a sterile lancet, press firmly against the finger

to make a puncture.

 The first drop contains excess tissue fluid and must be wiped away.

Collect the drops of blood into the collection device by gently massaging

the finger.

 Avoid excessive pressure that may squeeze tissue fluid into the drop of

blood or cause bruising.

 When full, cap and then gently invert the collection device 5-10 times to

mix the blood.

 Hold a gauze pad over the puncture site for a short time to stop the

bleeding.

 Dispose of the contaminated materials and lancet in the appropriate waste

containers.

 Place a band-aid on the patient’s finger or have someone continue to hold

gauze on the finger. (See “Use of Band-Aids in the Post Phlebotomy

policy.)

 Label the specimens before leaving the patient’s bedside.

Procedure for Capillary Puncture of the Heel:

 A heel puncture is performed on the lateral or medial plantar surface of the

foot. The area of the arch should be avoided, as should the posterior

curvature of the heel; a puncture in these areas could cause injury to the

underlying bone.

 All babies in the neonatal unit must be warmed before performing a

puncture. Begin by selecting the proper, approved lancet, such as:

 BD Microtainer Quikheel Lancet, 2.5 mm for full-term babies (green)

 BD Microtainer Quickheel Preemie Lancet, 1.75 mm for neonatal

babies (purple)

 Unistick2 Neonatal 18G, 1.2mm Lancet for neonatal babies less than

1000g (blue)

 Prepare the heel by cleaning it with a Chlorhexadine wipe. Allow it to air

dry.

 Grasp the foot, and using a sterile lancet, press firmly against the heel to

make a puncture.

 The first drop contains excess tissue fluid and must be wiped away.

Collect the drops of blood into the collection device by gently squeezing

the foot. Avoid excessive pressure that may squeeze tissue fluid into the

drop of blood or cause bruising.

 When full, cap and then gently invert the collection device 5-10 times to

mix the blood. Hold a gauze pad over the puncture site for a couple of

minutes to stop the bleeding, and then tie gauze around the foot. (See

“Use of Band-Aids in this policy.)

 The chlorhexidine is a concern for the premature babies in NICU as it can

be absorbed through the skin. For all NICU babies, once you have

collected the blood, wipe off the area with a sterile saline wipe, to remove

the chlorhexidine residue before tying a piece of gauze around the foot.

 Dispose of the contaminated materials and lancet in the appropriate waste

containers. Label the specimens before leaving the patient’s bedside.

References

Ernst, Dennis J. “Pediatric Pointers.” Center for Phlebotomy Education, Inc.

2004-2008, edited for accuracy 1/08.

Ernst, Dennis J. and Catherine Ernst. “Mastering Pediatric Phlebotomy.” Center

for Phlebotomy Education, Inc. Adapted from Phlebotomy for Nurses and

Nursing Personnel. HealthStar Press, Inc. 2001, updated 1/08.

Kiechle, Frederick L. So You’re Going to Collect a Blood Specimen: An

Introduction to Phlebotomy, 11th Edition. Northfield, IL: College of American

Pathologists, 2005.

NCCLS. Procedures and Devices for the Collection of Diagnostic Capillary Blood

Specimens; Approved Standard—Sixth Edition. CLSI document H04-A6.

Wayne, PA: Clinical and Laboratory Standards Institute; 2008.

Proper Handling of an Uncooperative Patient in an Outpatient Setting – Akron

Children’s Hospital