title: Platelet aggregation and coagulation factors in orthopedic surgery.
abstract: Hemostasis is a major concern during the perioperative period. Changes in platelet aggregation and coagulation factors may contribute to the delicate balance between thrombosis and bleeding. We sought to better understand perioperative hemostasis by investigating the changes in platelet aggregation and coagulation factors during the perioperative period. We performed a prospective cohort analysis of 70 subjects undergoing non-emergent orthopedic surgery of the knee (n = 28), hip (n = 35), or spine (n = 7) between August 2011 and November 2011. Plasma was collected preoperatively (T1), 1-h intraoperatively (T2), 1-h (T3), 24-h (T4) and 48-h (T5) postoperatively. Platelet function testing was performed using whole blood impedance aggregometry. Coagulation assays were performed for factor VII, factor VIII, von Willebrand Factor (vWF), and fibrinogen. Of the 70 patients, mean age was 64.1 ± 9.8 years, 61% were female, and 74% were Caucasian. Platelet activity decreased until 1 h postoperatively and then significantly increased above baseline at 24- and 48-h postoperatively. Compared to baseline, coagulation factors decreased intraoperatively. Factor VII activity continued to decrease, while FVIII, vWF, and fibrinogen all increased above baseline postoperatively. The results of our study indicate significant changes in platelet activity and coagulation factors during the perioperative period. Both platelet activity and markers of coagulation decrease during the intraoperative period and then some increase postoperatively. These changes may contribute to the hypercoagulabity and/or bleeding risk that occurs in the perioperative period. Future prospective studies aimed at correlating hemostatic changes with perioperative outcomes are warranted.
authors.affiliation: Department of Medicine, New York University Langone Medical Center, 530 First Avenue Skirball 9R, New York, NY, 10016, USA.
authors.forename: Brandon S
authors.initials: BS
authors.lastname: Oberweis
authors.forename: Germaine
authors.initials: G
authors.lastname: Cuff
authors.forename: Andrew
authors.initials: A
authors.lastname: Rosenberg
authors.forename: Luis
authors.initials: L
authors.lastname: Pardo
authors.forename: Michael A
authors.initials: MA
authors.lastname: Nardi
authors.forename: Yu
authors.initials: Y
authors.lastname: Guo
authors.forename: Ezra
authors.initials: E
authors.lastname: Dweck
authors.forename: Mitchell
authors.initials: M
authors.lastname: Marshall
authors.forename: David
authors.initials: D
authors.lastname: Steiger
authors.forename: Steven
authors.initials: S
authors.lastname: Stuchin
authors.forename: Jeffrey S
authors.initials: JS
authors.lastname: Berger
mesh_terms: D000368:Aged; D001777:Blood Coagulation / Q000502:physiology*; D001779:Blood Coagulation Factors / Q000032:analysis / Q000378:metabolism*; D015331:Cohort Studies; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D016343:Monitoring, Intraoperative / Q000379:methods*; D019637:Orthopedic Procedures / Q000639:trends*; D015539:Platelet Activation / Q000502:physiology*; D010974:Platelet Aggregation / Q000502:physiology*; D011182:Postoperative Care / Q000379:methods; D011300:Preoperative Care / Q000379:methods; D011446:Prospective Studies
chemical_list: D001779:Blood Coagulation Factors