Comparison of BD Vacutainer® Rapid Serum Tube and plasma for haemolysis markers in the emergency department.
BACKGROUND
In recent years, a rapid-clotting serum tube, BD Vacutainer® Rapid Serum Tube (RST™), was introduced to improve turn-around times for serum samples. Previous studies reported reduced concentrations of some markers of haemolysis in RST specimens compared to other serum or plasma samples. We aimed to compare RST to plasma tubes for haemolysis markers in an emergency department (ED) setting, where increased rates of haemolysis are commonly seen.


METHODS
Patients presenting to ED over an eight-day period had an RST, BD Vacutainer® PST™ II (plasma) Tube and BD Vacutainer® Heparin (non-gel, plasma) Tube collected. Blood was drawn from an intravenous cannula, and samples were promptly analysed for haemolysis index, potassium, phosphate, aspartate aminotrasferase (AST), magnesium and lactate dehydrogenase (LD).


RESULTS
A total of 347 patient samples were included, and 9.2% of the PST samples were haemolysed. The RST tubes had small increases in all of the haemolysis markers compared to both plasma tubes (P ≤ 0.005), except LD which was lower in the RST group. There were no significant differences in the proportion of results above the upper reference limit between the tubes, except for LD which had a lower proportion in RST samples (P ≤ 0.002).


CONCLUSIONS
Compared to plasma, RST specimens show small increases in several haemolysis markers, consistent with known differences between serum and plasma, but the proportion of elevated haemolysis markers is similar to plasma. In a setting with a high haemolysis rate such as ED, RST specimens provide a non-inferior sample type for markers of haemolysis.
Canterbury Health Laboratories, Christchurch, New Zealand Josh.Ryan@cdhb.health.nz.
J B
JB
Ryan
Canterbury Health Laboratories, Christchurch, New Zealand.
L A
LA
Stuart
Canterbury Health Laboratories, Christchurch, New Zealand.
S J
SJ
Southby
Emergency Department, Christchurch Hospital, Christchurch, New Zealand.
M P
MP
Than
Canterbury Health Laboratories, Christchurch, New Zealand.
R
R
Mackay
Canterbury Health Laboratories, Christchurch, New Zealand.
C M
CM
Florkowski
Canterbury Health Laboratories, Christchurch, New Zealand.
P M
PM
George
D000328:Adult; D000368:Aged; D000925:Anticoagulants / Q000494:pharmacology*; D015415:Biomarkers / Q000097:blood; D001800:Blood Specimen Collection; D004636:Emergency Service, Hospital; D005260:Female; D006461:Hemolysis / Q000187:drug effects*; D006493:Heparin / Q000494:pharmacology*; D006801:Humans; D008094:Lithium / Q000494:pharmacology*; D008297:Male; D008422:Materials Testing; D008875:Middle Aged; D009520:New Zealand; D010949:Plasma / Q000737:chemistry; D015203:Reproducibility of Results; D044967:Serum / Q000737:chemistry
D000925:Anticoagulants; D015415:Biomarkers; D006493:Heparin; D008094:Lithium
RST; Rapid Serum Tube; haemolysis