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Laboratory
analysis
Georg Alfthan
Selection of blood
measurements
• Core measurements:
• CVD risk factors
• Additional measurements:
• CVD, Diabetes, Dietary biomarkers
• Infectious disease markers
• Environmental exposure biomarkers
Critical pre-analytical issues
of blood collection
• Fasting - 8-14 hours, glucose, triglycerides
• Position of subject
• sitting
• 10 min rest
• lying  8% increase in blood volume
• Tourniquet - short duration
• Season - spring vs. winter: cholesterol
• Physical exercise
•
heavy training  dehydration
Documentation of blood
collection
• ID of phlebotomist
• Date and time of phlebotomy
• Time from last meal
• Number of tubes collected
• Posture and reason if supine
• Arm and reason if right
The procedure for specimen
collection, processing and storage
5
Type and order of blood tubes
1
2
FLS
0
LiH
e
3 ml
4 ml
kääntö ↑↓
18 kertaa
3
SEER
1
8 ml
Turn 18 times
4
5
DN
A
1
Hb
A1
c
9 ml
4 ml
6
7
SEER
2
EDTA
0
8 ml
9 ml
8
DN
A
2
9 ml
ml
Processing of blood tubes
analysis
Deep-freezing
Storage tubes
Storage tubes
Whole blood
Labelling of aliquots
Cryotube
-20 C
Cryo
Tube
-70 C
Storage of specimen
• Short term storage = - 20°C
- Core measurements
• Long term storage = - 70°C
- Additional measurements
Responsibility of National HES Laboratory ?
Selection of National HES
Laboratory
• All core measurements should be performed in
the same lab: National HES Lab (NHESL)
• Selection criteria: performance in external quality
assessment program (regular participation)
• Additional value: The lab is accredited by a
national organization
Recommendation for
analytical methods
• All analytical methods should be
documented and validated
• Documentation should be available
at National HES Laboratory (HESL)
and EHES Reference Laboratory (RL)
Standardization of analytical
data
•
Pilot calibration
Reference samples
•
•
2
1
NHESL
EHESRL
3
Analytical data
Satisfactory performance !
Performance of laboratories
Long term verification of bias
National EQA program
Bias of NHESL
Bias of EHESRL
CDC
Recommended goals for bias
of methods
Bias (%)
Precision
(CV%)
• Core analytes
Goal
• Serum tot chol
• Serum HDL chol
• Plasma glucose
3
8
6
Acceptable
5
10
?
2
3
3
Corrective measures
recommended for National HES
Labs if bias exceeds criteria
•
•
•
•
•
•
Check calibrators
Change reagents (kits)
Malfunctioning instruments
Wrong type of sample
Reagent not compatible with instrument
Change method or technique !
Long term quality control
• Documentation of all changes done
to methods and procedures
• Regular reporting to the central EHES
RL