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Comparison of stress-hemoconcentration correction techniques for stress-induced coagulation.

Austin AW, Patterson SM - Biomed Res Int (2013)

Bottom Line: For FVII:C, uncorrected AUC was significantly greater than AUC corrected arithmetically.For fibrinogen, uncorrected AUC was significantly greater than AUC corrected with saline or arithmetically.For D-dimer, uncorrected AUC was significantly greater than AUC corrected arithmetically.

View Article: PubMed Central - PubMed

Affiliation: Montreal Behavioural Medicine Centre, Hôpital du Sacré-Coeur de Montréal, Office J-3145, 5400 Boulevard Gouin Ouest, Montreal, Quebec, Canada H4J 1C5 ; Department of Exercise Science, Concordia University, Montreal, Quebec, Canada H4B 1R6 ; Research Centre, Hôpital du Sacré-Coeur de Montréal, Montreal, Quebec, Canada H4J 1C5.

ABSTRACT
When examining stress effects on coagulation, arithmetic correction is typically used to adjust for concomitant hemoconcentration but may be inappropriate for coagulation activity assays. We examined a new physiologically relevant method of correcting for stress-hemoconcentration. Blood was drawn from healthy men (N = 40) during baseline, mental stress, and recovery, and factor VII activity (FVII:C), factor VIII activity (FVIII:C), activated partial thromboplastin time (APTT), prothrombin time (PT%), fibrinogen, D-dimer, and plasma volume were determined. Three hemoconcentration correction techniques were assessed: arithmetic correction and two reconstitution techniques using baseline plasma or physiological saline. Area-under-the-curve (AUC) was computed for each technique. For FVII:C, uncorrected AUC was significantly greater than AUC corrected arithmetically. For PT%, uncorrected AUC was significantly greater than AUC corrected with saline or arithmetically. For APTT, uncorrected AUC was significantly less than AUC corrected with saline and greater than AUC corrected arithmetically. For fibrinogen, uncorrected AUC was significantly greater than AUC corrected with saline or arithmetically. For D-dimer, uncorrected AUC was significantly greater than AUC corrected arithmetically. No differences in AUC were observed for FVIII:C. Saline reconstitution seems most appropriate when adjusting for hemoconcentration effects on clotting time and activity. Stress-hemoconcentration accounted for the majority of coagulation changes.

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Differences in D-dimer across conditions (mean ± SEM). ∗: different from uncorrected and plasma reconstitution at P < .05. ∧: different from uncorrected at P < .001.
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fig6: Differences in D-dimer across conditions (mean ± SEM). ∗: different from uncorrected and plasma reconstitution at P < .05. ∧: different from uncorrected at P < .001.

Mentions: Due to budget restraints, plasma was analyzed for D-dimer only at baseline and stress in only 37 participants. Repeated measures ANOVA indicated a marginally significant time-by-plasma manipulation interaction, F(3, 108) = 2.93, ε = .617, P = .064, as observed in Figure 6. Given that D-dimer was only analyzed at baseline and stress, only 10 pairwise comparisons were made, with an adjusted significance level of αadj = .005. AUC was calculated from baseline and stress values only. Friedman's test was significant for D-dimer AUC, X2(3) = 16.28, P = .001. Wilcoxon Signed-Rank tests suggest that uncorrected AUC (M = 1289.23 ± 438.82) was significantly greater than AUC corrected arithmetically (M = 1241.25 ± 420.37, P < .001) and marginally greater than AUC corrected with saline (M = 1209.84 ± 448.58, P = .033). AUC corrected with plasma (M = 1274.22 ± 476.81) was marginally greater than AUC corrected with saline (P = .025). Other comparisons were nonsignificant (Ps > .28).


Comparison of stress-hemoconcentration correction techniques for stress-induced coagulation.

Austin AW, Patterson SM - Biomed Res Int (2013)

Differences in D-dimer across conditions (mean ± SEM). ∗: different from uncorrected and plasma reconstitution at P < .05. ∧: different from uncorrected at P < .001.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3814105&req=5

fig6: Differences in D-dimer across conditions (mean ± SEM). ∗: different from uncorrected and plasma reconstitution at P < .05. ∧: different from uncorrected at P < .001.
Mentions: Due to budget restraints, plasma was analyzed for D-dimer only at baseline and stress in only 37 participants. Repeated measures ANOVA indicated a marginally significant time-by-plasma manipulation interaction, F(3, 108) = 2.93, ε = .617, P = .064, as observed in Figure 6. Given that D-dimer was only analyzed at baseline and stress, only 10 pairwise comparisons were made, with an adjusted significance level of αadj = .005. AUC was calculated from baseline and stress values only. Friedman's test was significant for D-dimer AUC, X2(3) = 16.28, P = .001. Wilcoxon Signed-Rank tests suggest that uncorrected AUC (M = 1289.23 ± 438.82) was significantly greater than AUC corrected arithmetically (M = 1241.25 ± 420.37, P < .001) and marginally greater than AUC corrected with saline (M = 1209.84 ± 448.58, P = .033). AUC corrected with plasma (M = 1274.22 ± 476.81) was marginally greater than AUC corrected with saline (P = .025). Other comparisons were nonsignificant (Ps > .28).

Bottom Line: For FVII:C, uncorrected AUC was significantly greater than AUC corrected arithmetically.For fibrinogen, uncorrected AUC was significantly greater than AUC corrected with saline or arithmetically.For D-dimer, uncorrected AUC was significantly greater than AUC corrected arithmetically.

View Article: PubMed Central - PubMed

Affiliation: Montreal Behavioural Medicine Centre, Hôpital du Sacré-Coeur de Montréal, Office J-3145, 5400 Boulevard Gouin Ouest, Montreal, Quebec, Canada H4J 1C5 ; Department of Exercise Science, Concordia University, Montreal, Quebec, Canada H4B 1R6 ; Research Centre, Hôpital du Sacré-Coeur de Montréal, Montreal, Quebec, Canada H4J 1C5.

ABSTRACT
When examining stress effects on coagulation, arithmetic correction is typically used to adjust for concomitant hemoconcentration but may be inappropriate for coagulation activity assays. We examined a new physiologically relevant method of correcting for stress-hemoconcentration. Blood was drawn from healthy men (N = 40) during baseline, mental stress, and recovery, and factor VII activity (FVII:C), factor VIII activity (FVIII:C), activated partial thromboplastin time (APTT), prothrombin time (PT%), fibrinogen, D-dimer, and plasma volume were determined. Three hemoconcentration correction techniques were assessed: arithmetic correction and two reconstitution techniques using baseline plasma or physiological saline. Area-under-the-curve (AUC) was computed for each technique. For FVII:C, uncorrected AUC was significantly greater than AUC corrected arithmetically. For PT%, uncorrected AUC was significantly greater than AUC corrected with saline or arithmetically. For APTT, uncorrected AUC was significantly less than AUC corrected with saline and greater than AUC corrected arithmetically. For fibrinogen, uncorrected AUC was significantly greater than AUC corrected with saline or arithmetically. For D-dimer, uncorrected AUC was significantly greater than AUC corrected arithmetically. No differences in AUC were observed for FVIII:C. Saline reconstitution seems most appropriate when adjusting for hemoconcentration effects on clotting time and activity. Stress-hemoconcentration accounted for the majority of coagulation changes.

Show MeSH
Related in: MedlinePlus