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EDTA contamination in laboratory specimens-effect of an awareness campaign
Aamir Ijaz1, Maqsood-ul-Hassan, Iqbal Muhammad Khan
1Department Of Pathology, Combined Military Hospital, Peshawar. ijaz_aamir@hotmail.com
Objective:
To measure the effects of awareness campaign on the frequency of EDTA contamination.
Study Design:
A cohort study.
Place And Duration Of Study:
The study was carried out in Combined Military Hospital, Peshawar, from October to December 2008.
Methodology:
A cohort of 200 doctors, nurses and paramedical staff involved in sample collection for laboratory investigations were selected for this three phased study. In all samples with plasma potassium level > 6.0 mmol/L, plasma Ca++ was measured for one month before, during and after a campaign of correct filling order of sample tubes for two weeks. Renal function test and LDH were also measured to rule out chronic renal failure and in-vitro haemolysis, respectively. Fisher's exact test was used for comparison of frequency of hyperhalemia.
Results:
There was a significant decrease (75%, p < 0.01) in the cases of spurious hyperkalaemia and hypocalcaemia.
Conclusion:
EDTA contamination is a common and important source of pre-analytical error which can be prevented to some extent by education of medical and nursing staff.
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