The investigators will obtain thromboelastography (TEG) on pediatric patients admitted to the
Rady Children's Hospital ICU after traumatic brain injury on admission to our ICU and after
24 hours of care. The investigators hypothesize that TEG will identify abnormalities of
coagulation that are not identified by traditional coagulation studies, i.e. prothrombin time
(PT), activated partial thromboplastin time (aPTT), and international normalized ratio (INR).