Thromboelastography as a better indicator of hypercoagulable state after injury than prothrombin time or activated partial thromboplastin time.
OBJECTIVE
To investigate the hemostatic status of critically ill, nonbleeding trauma patients. We hypothesized that a hypercoagulable state exists in patients early after severe injury and that the pattern of clotting and fibrinolysis are similar between burned and nonburn trauma patients.


METHODS
Patients admitted to the surgical or burn intensive care unit within 24 hours after injury were enrolled. Blood samples were drawn on days 0 through 7. Laboratory tests included prothrombin time (PT), activated partial thromboplastin time (aPTT), levels of activated factor XI, D-dimer, protein C percent activity, antithrombin III percent activity, and thromboelastography (TEG).


RESULTS
Study subjects were enrolled from April 1, 2004, to May 31, 2005, and included nonburn trauma patients (n = 33), burned patients (n = 25), and healthy (control) subjects (n = 20). Despite aggressive thromboprophylaxis, three subjects (2 burned and 1 nonburn trauma patients [6%]) had pulmonary embolism during hospitalization. Compared with controls, all patients had prolonged PT and aPTT (p < 0.05). The rate of clot formation (alpha angle) and maximal clot strength were higher for patients compared with those of controls (p < 0.05), indicating a hypercoagulable state. Injured patients also had lower protein C and antithrombin III percent activities and higher fibrinogen levels (p < 0.05 for all). Activated factor XI was elevated in 38% of patients (control subjects had undetectable levels).


CONCLUSIONS
Thromboelastography analysis of whole blood showed that patients were in a hypercoagulable state; this was not detected by plasma PT or aPTT. The high incidence of pulmonary embolism indicated that our current prophylaxis regimen could be improved.
Park
Myung S
MS
U S Army Institute of Surgical Research, Fort Sam Houston, Texas, USA. park.myung@mayo.edu
Martini
Wenjun Z
WZ
Dubick
Michael A
MA
Salinas
Jose
J
Butenas
Saulius
S
Kheirabadi
Bijan S
BS
Pusateri
Anthony E
AE
Vos
Jeffrey A
JA
Guymon
Charles H
CH
Wolf
Steven E
SE
Mann
Kenneth G
KG
Holcomb
John B
JB
D000328:Adult; D000990:Antithrombin III / Q000032:analysis; D016022:Case-Control Studies; D015945:Factor XIa / Q000032:analysis; D005260:Female; D006801:Humans; D007362:Intensive Care Units; D008297:Male; D008875:Middle Aged; D010314:Partial Thromboplastin Time; D011486:Protein C / Q000032:analysis; D011517:Prothrombin Time; D011655:Pulmonary Embolism / Q000175:diagnosis / Q000209:etiology; D013916:Thrombelastography; D019851:Thrombophilia / Q000175:diagnosis* / Q000209:etiology*; D054556:Venous Thromboembolism / Q000175:diagnosis / Q000209:etiology; D014947:Wounds and Injuries / Q000150:complications*
D011486:Protein C; D000990:Antithrombin III; D015945:Factor XIa