title: The order of draw of blood specimens into additive containing tubes not affect potassium and calcium measurements.
abstract: The effect of order of draw when taking blood into tubes containing additive was investigated in 47 medical inpatients; 12 of these patients acted as a control group. The samples were analysed in the order in which they were withdrawn. The results of potassium and calcium concentrations did not differ significantly between groups. Manufacturers recommend a specific order of draw when taking blood using vacuum based blood collection systems, which are routinely used in many hospitals. The results of this study, however, show that order of draw has no effect on calcium or potassium concentrations.
authors.affiliation: Department of Medicine and Therapeutices, Western Infirmary, Glasgow.
authors.forename: A
authors.initials: A
authors.lastname: Majid
authors.forename: D C
authors.initials: DC
authors.lastname: Heaney
authors.forename: N
authors.initials: N
authors.lastname: Padmanabhan
authors.forename: R
authors.initials: R
authors.lastname: Spooner
mesh_terms: D001800:Blood Specimen Collection; D002118:Calcium / Q000097:blood*; D006801:Humans; D011188:Potassium / Q000097:blood*; D013048:Specimen Handling
chemical_list: D011188:Potassium; D002118:Calcium