Sonoclot Signature Analysis: A New Point-of-Care Testing Method for Defining Heat Stroke-Induced Coagulopathy

Abstract

Purpose

Data regarding the incidence of a coagulable state following heat stroke as assessed by Sonoclot signature analysis are limited. Our purpose was to appraise coagulopathy using a dynamic test capable of analyzing the entire coagulation cascade and to characterize coagulation in patients with heat stroke prior to transfusion.

Materials and Methods

The data of 106 patients were collected prospectively from the Critical Care Center of the General Hospital of Guangzhou Military Command. Coagulable state was defined as normal. Both hyper- and hypo-coagulable states were defined as coagulation defects. Hypercoagulability was defined as an activated clotting time (ACT) ≦195s and a clot rate (CR) >23, and hypocoagulability was defined as an ACT ≧119s and a CR < 7. The Sonoclot signature t examination was performed at the time of admission. Conventional tests, such as the prothrombin time (PT) and activated partial thromboplastin time (aPTT), were compared with Sonoclot monitoring to identify coagulation defects.

Results

The average age of the 106 patients was 23.2±2.5 years. There were 102 males (96.3%) and 4 females (3.7%). Thirty-four patients (32.1%) were hypercoagulable and 44 patients (41.5%) were hypocoagulable at the time of admission; 28 patients (26.4%) had no evidence of a coagulopathy. Patients with hypocoagulability, unlike patients with hypercoagulability, had a higher sequential Organ Failure Assessment score, indicating a more severe multiple organ dysfunction score. Mortality was 5.9% in patients with hypercoagulability compared with 3.5% in patients with normal coagulation, and 18.1% in patients with a hypocoagulable state ( P < 0.05). ACT was a predictor of mortality, while the CR and platelet function did not show statistical significance.

Conclusion

This study determined the clinical outcomes and prognostic value of coagulability in patients with heat stroke, as defined by Sonoclot signature analysis at the time of admission.