TY - JOUR
T1 - Mixing of thawed coagulation samples prior to testing
T2 - Is any technique better than another?
AU - Lima-Oliveira, Gabriel
AU - Adcock, Dorothy M
AU - Salvagno, Gian Luca
AU - Favaloro, Emmanuel J
AU - Lippi, Giuseppe
N1 - Copyright © 2016 The Canadian Society of Clinical Chemists. Published by Elsevier Inc. All rights reserved.
PY - 2016/12
Y1 - 2016/12
N2 - OBJECTIVE: Thus study was aimed to investigate whether the mixing technique could influence the results of routine and specialized clotting tests on post-thawed specimens.METHODS: The sample population consisted of 13 healthy volunteers. Venous blood was collected by evacuated system into three 3.5mL tubes containing 0.109mmol/L buffered sodium citrate. The three blood tubes of each subject were pooled immediately after collection inside a Falcon 15mL tube, then mixed by 6 gentle end-over-end inversions, and centrifuged at 1500g for 15min. Plasma-pool of each subject was then divided in 4 identical aliquots. All aliquots were thawed after 2-day freezing -70°C. Immediately afterwards, the plasma of the four paired aliquots were treated using four different techniques: (a) reference procedure, entailing 6 gentle end-over-end inversions; (b) placing the sample on a blood tube rocker (i.e., rotor mixing) for 5min to induce agitation and mixing; (c) use of a vortex mixer for 20s to induce agitation and mixing; and (d) no mixing. The significance of differences against the reference technique for mixing thawed plasma specimens (i.e., 6 gentle end-over-end inversions) were assessed with paired Student's t-test. The statistical significance was set at p<0.05.RESULTS AND CONCLUSION: As compared to the reference 6-time gentle inversion technique, statistically significant differences were only observed for fibrinogen, and factor VIII in plasma mixed on tube rocker. Some trends were observed in the remaining other cases, but the bias did not achieve statistical significance. We hence suggest that each laboratory should standardize the procedures for mixing of thawed plasma according to a single technique.
AB - OBJECTIVE: Thus study was aimed to investigate whether the mixing technique could influence the results of routine and specialized clotting tests on post-thawed specimens.METHODS: The sample population consisted of 13 healthy volunteers. Venous blood was collected by evacuated system into three 3.5mL tubes containing 0.109mmol/L buffered sodium citrate. The three blood tubes of each subject were pooled immediately after collection inside a Falcon 15mL tube, then mixed by 6 gentle end-over-end inversions, and centrifuged at 1500g for 15min. Plasma-pool of each subject was then divided in 4 identical aliquots. All aliquots were thawed after 2-day freezing -70°C. Immediately afterwards, the plasma of the four paired aliquots were treated using four different techniques: (a) reference procedure, entailing 6 gentle end-over-end inversions; (b) placing the sample on a blood tube rocker (i.e., rotor mixing) for 5min to induce agitation and mixing; (c) use of a vortex mixer for 20s to induce agitation and mixing; and (d) no mixing. The significance of differences against the reference technique for mixing thawed plasma specimens (i.e., 6 gentle end-over-end inversions) were assessed with paired Student's t-test. The statistical significance was set at p<0.05.RESULTS AND CONCLUSION: As compared to the reference 6-time gentle inversion technique, statistically significant differences were only observed for fibrinogen, and factor VIII in plasma mixed on tube rocker. Some trends were observed in the remaining other cases, but the bias did not achieve statistical significance. We hence suggest that each laboratory should standardize the procedures for mixing of thawed plasma according to a single technique.
KW - Adult
KW - Blood Coagulation
KW - Female
KW - Healthy Volunteers
KW - Humans
KW - Male
KW - Middle Aged
KW - Reproducibility of Results
KW - Young Adult
U2 - 10.1016/j.clinbiochem.2016.10.009
DO - 10.1016/j.clinbiochem.2016.10.009
M3 - Article
C2 - 27769865
SN - 1873-2933
VL - 49
SP - 1399
EP - 1401
JO - Clinical Biochemistry
JF - Clinical Biochemistry
IS - 18
ER -