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Lab Manual for Moffitt-Long and Mount Zion

Lab Manual for SFGH

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Pediatric Blood Specimens



Often, only a small volume of blood can be drawn from a pediatric patient. For maximum benefit from the limited sample, the specimen is handled individually, with special emphasis on micro techniques and procedures designed to conserve the specimen. Duplicate determinations (the standard procedure for assuring accurate results) may not be done if the sample is not large enough to perform all the requested tests.


This section describes special procedures for specimen collection from infants and children, and lists the minimum sample volume required for individual tests or test combinations. Please consult the tables before collecting the blood specimen.


All containers of patient specimens must be protected by plastic biohazard or similar bags during transportation to the laboratory. The requisition must be placed in the outside pocket of the bag. Do not staple the requisition to the bag.


  1. OBTAINING BLOOD SPECIMENS FROM INFANTS

  1. Warm the patient's foot with a warming device or towel (do not exceed 42 degrees C) for 10 minutes before obtaining sample.

  2. Assemble the appropriate tubes for blood collection. If a micro collection container does not have the flo-top collector attachment, detach one from a microtainer that does.

  3. Choose the appropriate lancet for heelstick. It is important to prick only the lateral aspect of the heel and never the medial aspect of the heel.

  4. Cleanse the area thoroughly with alcohol and dry with sterile gauze before pricking. The depth of the cut is no more than 2.4 mm. Repeated lancing of the same area may result in macerations, skin breakdown, and increase the chance for infection. Deep puncture or lancing the curvature of the heel may result in osteochondritis. Lancing the medial aspect of the heel may result in puncture of the medial plantar artery.

  5. Hold foot firmly to produce a good blood flow. Wipe off the initial drop of blood with sterile gauze to remove alcohol which may dilute specimen or hemolyze the RBC’s.

  6. Touch tip of flo-top collector to the underside of drop; do not touch middle of drop. Blood should flow freely through the flo-top collector and down the tube wall. Allow blood to flow by gravity through the flo-top collector to the required volume. Avoid excessive milking of the puncture site, since this may cause hemolysis and contamination with tissue fluids.

  7. For chemistry specimens, scraping too hard with the flo-top collector against the heel during collection may cause hemolysis.

  8. For hematology specimens, tap the micro collection container gently after collection of each drop of blood to mix it with the anticoagulant and prevent clotting.

  9. After drawing is done, remove flo-top collector and discard. Replace the lid and gently invert 8-10 times to ensure proper mixing of the sample.

  10. Apply pressure on the wound using a sterile gauze pad until bleeding stops. Use a small adhesive dressing only if it is needed.

  11. Place the labeled tube in a biohazard or similar specimen bag for delivery to the laboratory. The requisition must be placed in the outside pocket. Follow the procedures under the Delivering Specimens section of this manual.

  12. Capillary collectors are not the same as Micro-hematocrit tubes. Capillary collectors are available in a lavender container (EDTA) for Hematology tests and amber or green containers for Clinical Chemistry procedures.

  1. MINIMUM SPECIMEN REQUIREMENTS FOR PEDIATRIC TESTS

The preferred microtainer for chemistry testing is the amber SST microtainer (500 µL).

When collecting blood specimens (venous, capillary, arterial) for chemistry testing from newborns (hematocrit greater than 50%), we recommend the use of green top microtainers with heparin (400 µL). This tube type is our smallest volume blood collection tube, and will facilitate a maximum yield of plasma from whole blood. In addition, the minimum whole blood requirements listed below are based on an average hematocrit value of 50%. The resulting volume of plasma after centrifugation and separation from cells should meet the minimum amount of plasma required to do one analysis of the specimen.

Repeat analysis would require collection of additional blood samples.


ASSAY

MIN. VOL SERUM/PLASMA

TUBE

Acetaminophen

120

1 SST Amber Microtainer (full 500 µL)

Albumin

120

1 SST Amber Microtainer (full 500 µL)

Anti HCV

200 µL

2 SST Amber Microtainer (full 500 µL)

Bilirubin (Total and/or Direct)

120

1 SST Amber Microtainer (full 500 µL)

Blood Urea Nitrogen

120

1 SST Amber Microtainer (full 500 µL)

BNP

200

2 EDTA Lavender Microtainer

C Reactive Protein High Sensitivity

300 µL

2 SST Amber Microtainer (full 500 µL)

Calcium

120

1 SST Amber Microtainer (full 500 µL)

Carbamezepine

125

1 SST Amber Microtainer (full 500 µL)

Carbon Dioxide

120

1 SST Amber Microtainer (full 500 µL)

CD4/CD8 by Flow Cytometry

200 µL

500 µL EDTA

Chloride

120

1 SST Amber Microtainer (full 500 µL)

Cholesterol

120

1 SST Amber Microtainer (full 500 µL)

Complement C3

300 µL

2 SST Amber Microtainer (full 500 µL)

Complement C4

300 µL

2 SST Amber Microtainer (full 500 µL)

Copper

600 µL

1/2 Royal Blue top

Cortisol

130

1 SST Amber Microtainer (full 500 µL)

Creatinine

120

1 SST Amber Microtainer (full 500 µL)

Digoxin

160

1 SST Amber Microtainer (full 500 µL)

Ferritin

140

1 SST Amber Microtainer (full 500 µL)

FSH

Cannot use microcontainers for this test

FT4

140

1 SST Amber Microtainer (full 500 µL)

G-6PD

150 + CBC

1 EDTA Lavender Microtainer

Gentamicin

125

1 SST Amber Microtainer (full 500 µL)

Glucose

120

1 SST Amber Microtainer (full 500 µL)

HA1c

100 µL

500 µL EDTA

Haptoglobin

300 µL

2 SST Amber Microtainer (full 500 µL)

HCG

160

1 SST Amber Microtainer (full 500 µL)

Hep A IgM

200 µL

2 SST Amber Microtainer (full 500 µL)

Hep A Total Antibody

200 µL

2 SST Amber Microtainer (full 500 µL)

Hep B Core IgM

200 µL

2 SST Amber Microtainer (full 500 µL)

Hep B Core Total Antibody

300 µL

2 SST Amber Microtainer (full 500 µL)

Hep B Surf Antibody

300 µL

2 SST Amber Microtainer (full 500 µL)

Hep B Surf Antigen

300 µL

2 SST Amber Microtainer (full 500 µL)

Hepatis Panel Acute (HEPP)

800 µL

4 SST Amber Microtainer (full 500 µL)

Hepatitis Panel Source (HEPS)

1.0 mL

5 SST Amber Microtainer (full 500 µL)

HGBV-Hemoglobinopathy Variants

500 µL

500 µL EDTA

Immunoglobulin A (IgA)

300 µL

2 SST Amber Microtainer (full 500 µL)

Immunoglobulin G (IgG)

300 µL

2 SST Amber Microtainer (full 500 µL)

Immunoglobulin M (IgM)

300 µL

2 SST Amber Microtainer (full 500 µL)

Insulin

125

1 SST Amber Microtainer (full 500 µL)

Lead

120

1 EDTA Lavender Microtainer

Magnesium

120

1 SST Amber Microtainer (full 500 µL)

METB

120

1 SST Amber Microtainer (full 500 µL)

METC

200

2 SST Amber Microtainer (full 500 µL)

Phenobarbital

120

1 SST Amber Microtainer (full 500 µL)

Phenytoin

120

1 SST Amber Microtainer (full 500 µL)

Phosphorous

120

1 SST Amber Microtainer (full 500 µL)

Potassium

120

1 SST Amber Microtainer (full 500 µL)

Reumatoid Factor,
Quantitative

300 µL

2 SST Amber Microtainer (full 500 µL)

Salicylate

120

1 SST Amber Microtainer (full 500 µL)

Sodium

120

1 SST Amber Microtainer (full 500 µL)

Theophylline

130

1 SST Amber Microtainer (full 500 µL)

Tobramycin

160

1 SST Amber Microtainer (full 500 µL)

TSH

350

3 SST Amber Microtainer (full 500 µL)

Valproic Acid

140

1 SST Amber Microtainer (full 500 µL)

Vancomycin

150

1 SST Amber Microtainer (full 500 µL)

Vit B12

300

Cannot use microcontainers for this

Zinc

600 µL

1/2 Royal Blue top


Note: call Lab for minimum requirements on combination orders


METB: Na, K, CL, CO2, CREA, BUN, GLUC, CA, GAP, eGFR


METC: Na, K, CL, CO2, CREA, BUN, GLUC, CA, TBIL, TP, ALB, ALT, AST, ALKP, GAP, eGFR,


HEPP: HAIM, HBAG, HBCM, HCV


HEPS: HBAG, HBSB, HBCM, HBTC, HCV




TRANSFUSION SERVICE

(BLOOD BANK) TESTS:

Pediatric Minimum, whole blood volume
(mL)


Type and Crossmatch

1

Use lavender top tube



HEMATOLOGY TESTS:

Pediatric Minimum, whole blood volume(mL)



Maximum (mL)

COLLECTION CONTAINER – Lavender top tube (4 mL)

Complete Blood Count and platelet

1

4

Complete Blood Count, platelets and reticulocyte

1

4

Complete Blood Count with Sed Rate

3

4

Zinc Protoporphyrin

1

4





HEMATOLOGY TESTS:

Pediatric Minimum, whole blood volume (mL)



Maximum (mL)

COLLECTION CONTAINER – Lavender top tube (2 mL)

Complete Blood Count with differential, reticulocyte, and platelets

0.5

2



MICRO COLLECTION CONTAINER – Pink top EDTA microtainer

Complete Blood Count, Differential, Platelet, and reticulocyte

0.3

0.5


COLLECTION CONTAINER – Blue top tube (1.8 mL)

Prothrombin Time and/or Partial Thromboplastin Time, and/or Fibrinogen, (when hematocrits are less than 55%).

1.8

1.8


If the hematocrit is greater than 55%, obtain a special pediatric blue top tube kept in the nursery (6H) refrigerator. It contains 0.17 mL of sodium citrate and should be filled only up to the black line (2.25 mL of whole blood).

Note: This tube has no vacuum, so blood should be collected with a syringe then transferred into the tube up to the black line. This tube should be used when the hematocrit is 56 to 70%.



MICROBIOLOGY TESTS

Pediatric Minimum, whole blood volume (mL)


Maximum (mL)

Blood Culture for bacteria or fungi

0.5 mL/bottle

(5 mL/bottle recommended)

10 mL/bottle

Blood Culture for Mycobacteria (bright green top tube)

3 mL

5 mL

Blood Parasites (lavender top tube)

3 mL

5 mL



REFER TO THE ALPHABETICAL LIST OF TESTS FOR FURTHER INFORMATION. REFERENCE VALUES FOR PEDIATRIC PATIENTS WILL BE FOUND UNDER THE INDIVIDUAL TEST IN THE ALPHABETICAL LIST OF TESTS .


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