Introduction: Recent reports using thrombelastography have suggested that neurosurgical patients develop a hypercoagulable state in the postoperative period. Since venous thromboembolism is a potentially life threatening complication in these patients, we studied a similar population in our institution.
Methods: We conducted a prospective pilot study to evaluate postoperative coagulation changes in critically ill cancer patients after craniotomy. Data collected included demographics, diagnoses, severity of illness, all hematological information (coagulation tests included conventional and TEG), therapies, and complications. Analysis included descriptive statistics, and multivariate regression analysis.
Results: Eleven patients were included in the study. Mean age was 52 +/- 17 years, BMI 28 +/- 6.5, APACHE II and SOFA scores were 11.18 +/- 5.0 and 3.82 +/- 1.6 respectively. The Coagulation Index (CI), which is derived from the measured values of R, K, MA, and alpha angle was 1.22 +/- 3.5, R 4.2 +/- 1.6, K 2.0 +/- 2.1, MA 60.78 +/- 5.97, and alpha angle 66.88 +/- 14.9; while the Thrombodynamic Potential Index (TPI), which is derived from the measured values of K and MA only was 32.48 +/- 21. The CI correlated significantly with R, K, alpha angle, MA, TMA, TPI, PMA, E, A30 and A60 but not with the PTT, INR, or SOFA and APACHE II scores. One patient was hypocoagulable by CI and TPI values; in contrast, nine patients were hypercoagulable by TPI but only one by CI. There were no cases of VTE.
Conclusions: Hypercoagulability as defined by the CI was not a common finding in this study. Although the TPI indicated hypercoagulability in a large number of patients, we do not believe it is a good tool to assess the patient's clotting status or predictor of thrombosis because in contrast to the CI, it does not take into account the enzymatic portions of the clotting cascade. A larger TEG study is warranted to determine the clinical significance of these changes in this and other populations.