Effect of hypothermia on serum electrolyte, inflammation, coagulation, and nutritional parameters in patients with severe traumatic brain injury

Introduction: We evaluated the effect of induced hypothermia on biochemical parameters in patients with severe traumatic brain injury. Methods: We obtained hemoglobin, hematocrit, white blood count, lymphocyte count, platelet count, and serum concentrations of sodium, potassium, glucose, albumin, and C-reactive protein, and prothrombin time, hepaplastin test, activated partial thromboplastin time, antithrombin-III, α2PI, and nitrogen excretion on the day of admission, and on days 1, 3, 5, 7, 14, and 21 after the injury in 31 patients with severe head injury who were treated with hypothermia of 33°ranging from 48 to 72 hours. We selected 33 normothermic patients as a control group; these patients were selected from patients who had been treated before hypothermia was used as a treatment modality, by the same criteria for hypothermia therapy. We compared the biochemical markers and rectal temperature and intracranial pressure in the hypothermia group with those in the normothermia group. Outcome was assessed using the Glasgow Outcome Scale at 6 months after injury. Results: The demographic characteristics, severity, and outcome were similar in the hypothermia and normothermia group. Intracranial pressure was significantly decreased by hypothermia. Serum potassium concentration decreased significantly during hypothermia. White blood cell counts and C-reactive protein levels were higher after rewarming in the hypothermia group, and these were also higher in the patients with infectious complications, although the incidence of infectious complications did not differ between the hypothermia and normothermia groups. There were no statistically significant prolongations of activated partial thromboplastin time and no decline in prothrombin time with hypothermia. Platelet count, antithrombin-III, and α2PI did not differ significantly between the two groups. Conclusion: Hypothermia of 33° for 48–72 hours does not appear to increase the risk for coagulopathy and infections, although hypothermic patients exhibited significant increments in inflammatory markers such as C-reactive protein and white blood counts after rewarming.