Blood Sampling in NICU
Laboratory Specimen Requirements

Reviewed by Cathy Brehmer- Lab Plus

April 2014

Clinical Guidelines Back Newborn Services Home Page
Arterial gas NICU Radiometer Gas Machine Biochemistry Haematology
Drug Levels Blood Bank Other Tests Capillary Sampling Devices

Tests Volume Container

Arterial gas

  • Includes:Na, K, Glucose, Hb, Hct, MetHb.
  • NICU Radiometer machine also measures bilirubin and lactate
0.3ml Plastic, heparinised, 1mL Blood Gas syringe

NICU Radiometer Gas Machine

  • Capillary gas - includes:
    Na, K, Glucose, Bilirubin, Hb, Hct, MetHb, lactate
95 uL Gaslyte
  • Glucose  only
35 uL Small capillary tube
  • Bilirubin only
35 uL Small capillary tube

Laboratory Gas

  • Capillary gas - includes:
    Na, K, Glucose, Hb, Hct
0.2 ml

A full capillary gas tube

Biochemistry Laboratory

  • SBR (total) only
0.3 ml

Green top (heparinised)

  • Total & Direct SBR

Green top (heparinised)

N.B.: Full Biochemistry including all or any combination
  • Electrolytes, Ca, Gluc, Creat, Urea, LFT, SBR, Mg, PO4

Green top (heparinised)

  • When collecting 3 – 4 tests
LFT – Liver Function Tests
  • Bilirubin, AST, ALT, GGT, & ALP
0.7ml Green top (heparinised)
Thyroid Function Tests


  • TSH, Free T3 & T4
0.7ml Green top (heparinised)
LFT & Thyroid Function Tests 0.9ml Green top (heparinised)
CRP (C-Reactive Protein) 0.3 – 0.5 ml  (depending on PCV) Green top (heparinised)


Full Blood Count 0.2 ml Purple top (EDTA)
Coagulation Screen
  • N.B. – NICU stock – if not available obtain from PICU – ( not Lab. incorrect size tube for neonates, larger volume required)
1.0 ml
Venous / Arterial
Blue  top micro-container
Ferritin 0.3 ml Green top (heparinised)
Whole Blood PR/INR &/or APTT Contact Lab Special container
G6PD 0.3 ml Purple top (EDTA)

Drug Levels

  • Amikacin
  • Gentamicin
  • Vancomycin
  • Phenobarbitone
  • Phenytoin
  • Theophylline
0.4 ml

Remainder of these
drug levels
require 0.3ml for 1 assay,
0.5 for more than 1

Green top container
Vitamin A
  • All samples taken for vitamin levels must be wrapped in tinfoil
0.4 ml Yellow top
(plain tube = no anticoagulant)
Vitamin D 0.3 ml
Vitamin E 0.4 ml

Blood Bank

Will only accept  ‘REQUEST  FOR  BLOOD COMPONENTS  OR  PRODUCTS’ Form for blood samples – not Laboratory Form – complete ‘TESTS REQUIRED’ section

Blood Bank require their BLOOD  SAMPLES  to be legibly HAND LABELLED using the specific labels, with:

  • patient’s first & last names
  • NHI number
  • DOB
  • date & time of collection
  • signature/initials of collector
Group & Coombs 0.5 ml Purple top
Neonatal Crossmatch 0.5 ml Purple top

Other Tests

Neonatal  Zinc  Level 0.3 ml
Arterial or Venous sample
Green top (heparinised)
Lactate 0.3 ml Grey top
Albumin 0.3 ml Green top
  • Level only
0.3 ml Green top (heparinised) 
TORCH  Screen 0.6ml Yellow top
Hepatitis screen 0.6ml Yellow top
Karyotype 1-2ml arterial or venous Green top
  • Other tests requested which are not routinely required for NICU infants – PLEASE consult the Laboratory staff for information on the amount of blood required and the appropriate container to use for the particular MICRO-COLLECT, also state for NEONATE.

  • For infants with a high PCV (often new admissions) when the blood clots easily causing difficulty in obtaining a result via the Radiometer Gas Machine, we have a supply of 55uL glass capillary tubes containing extra Heparin which may ensure you obtain a result – please ask the CCN for these capillary tubes when required.

Capillary Blood Sampling Devices    
Tenderfoot– Micro-preemie Blue
For infants up to 1000 grams
Quikheel - Preemie Lancet Mauve
For infants 1005-1500 grams
  • Depth 0.85mm
  • Length 1.75mm
  • May also be used for a small collect  of 35µL ONLY = glucose only or bilirubin only via Radiometer Gas Machine.
Quikheel - Infant Lancet Teal
For infants >1500 grams
  • Depth 1.00mm
  • Length 2.50mm