Effect on lipid, complete blood count and blood proteins of a standardized preparation for drawing blood: a randomized controlled trial.
OBJECTIVE
To compare a standardized recommended procedure for drawing blood to measure blood lipid and lipoprotein levels with the procedure commonly used in clinical practice. The aim was to see if hemoconcentration and spuriously elevated lipid levels could be avoided.


METHODS
An open randomized crossover clinical trial.


METHODS
The University of Calgary.


METHODS
Twenty-five patients with dyslipidemia.


METHODS
Blood drawing using a standardized procedure in which the patient remained seated for 5 minutes before blood collection and tourniquet use was minimized or avoided.


METHODS
Differences in lipid levels between the usual clinical procedure and the recommended procedure for drawing blood.


RESULTS
Prior to drawing blood, laboratories have sat patients for an average of 1.4 minutes (95% CI, 0.9 to 1.9) and used a tourniquet in every patient. In the standardized procedure, patients rested for an average of 5.6 minutes (95% CI 5.0 to 6.2), and a tourniquet was used briefly in only 3 of 23 patients. There were no differences in lipid and lipoprotein values and no clinically significant difference in hemoglobin or albumin levels or in the calculation of hemoconcentration.


CONCLUSIONS
Efforts to rest patients and avoid tourniquet use when drawing blood for assessment of lipid levels are unlikely to be useful.
Campbell
N R
NR
Division of General Internal Medicine and Geriatrics, University of Calgary, Alta. ncampbel@ucalgary.ca
Edwards
A L
AL
Brant
R
R
Jones
C
C
Mitchell
D
D
D001772:Blood Cell Count; D001798:Blood Proteins / Q000032:analysis*; D001800:Blood Specimen Collection / Q000379:methods*; D002784:Cholesterol / Q000097:blood; D008076:Cholesterol, HDL / Q000097:blood; D008078:Cholesterol, LDL / Q000097:blood; D018592:Cross-Over Studies; D006400:Hematocrit; D006454:Hemoglobins / Q000032:analysis; D006801:Humans; D006949:Hyperlipidemias / Q000097:blood; D008055:Lipids / Q000097:blood*; D012146:Rest; D012709:Serum Albumin / Q000032:analysis; D014111:Tourniquets; D014280:Triglycerides / Q000097:blood
D001798:Blood Proteins; D008076:Cholesterol, HDL; D008078:Cholesterol, LDL; D006454:Hemoglobins; D008055:Lipids; D012709:Serum Albumin; D014280:Triglycerides; D002784:Cholesterol