title: Efficacy of moderate hypothermia in patients with severe head injury and intracranial hypertension refractory to mild hypothermia.
abstract: OBJECTIVE
  This study was performed to determine whether moderate hypothermia (31 degrees C) improves clinical outcome in severely head injured patients whose intracranial hypertension cannot be controlled using mild hypothermia (34 degrees C).
  
  
  METHODS
  Twenty-two consecutive severely head injured patients who fulfilled the following criteria were included in this study: an intracranial pressure (ICP) that remained higher than 40 mm Hg despite the use of mild hypothermia combined with conventional therapies; and a Glasgow Coma Scale score of 8 or less on admission. After the failure of mild hypothermia in combination with conventional therapies; patients were exposed to moderate hypothermia as quickly as possible. As brain temperature was reduced from 34 to 31 degrees C, the volume of intravenous fluid infusion was increased significantly from 1.9 +/- 0.9 to 2.6 +/- 1.2 mg/kg/hr (p < 0.01), and the dose of dopamine infusion increased significantly from 4.3 +/- 3.1 to 8.2 +/- 4.4 microg/kg/min (p < 0.01). Nevertheless, mean arterial blood pressure and heart rate decreased significantly from 97.1 +/- 13.1 to 85.1 +/- 10.5 mm Hg (p < 0.01) and from 92.2 +/- 13.8 to 72.2 +/- 14.3 beats/minute at (p < 0.01) at 34 and 31 degrees C, respectively. Arterial base excess was significantly aggravated from -3.3 +/- 4 at 34 degrees C to -5.6 +/- 5.4 mEq/L (at 31 degrees C; p < 0.05). Likewise, serum potassium concentration, white blood cell counts, and platelet counts at 31 degrees C decreased significantly compared with those at 34 degrees C (p < 0.01). In 19 (86%) of 22 patients, elevation of ICP could not be prevented using moderate hypothermia. In the remaining three patients. ICP was maintained below 40 mm Hg by inducing moderate hypothermia; however, these three patients died of multiple organ failure. These results clearly indicate that moderate hypothermia induces complications more severe than those induced by mild hypothermia without improving outcomes.
  
  
  CONCLUSIONS
  The authors concluded that moderate hypothermia is not effective in improving clinical outcomes in severely head injured patients whose ICP remains higher than 40 mm Hg after treatment with mild hypothermia combined with conventional therapies.
authors.affiliation: Department of Traumatology, Osaka University Graduate School of Medicine, Suita-shi, Osaka, Japan. shiozaki@hp-emerg.med.osaka-u.ac.jp
authors.forename: Tadahiko
authors.initials: T
authors.lastname: Shiozaki
authors.forename: Yoshikazu
authors.initials: Y
authors.lastname: Nakajima
authors.forename: Mamoru
authors.initials: M
authors.lastname: Taneda
authors.forename: Osamu
authors.initials: O
authors.lastname: Tasaki
authors.forename: Yoshiaki
authors.initials: Y
authors.lastname: Inoue
authors.forename: Hitoshi
authors.initials: H
authors.lastname: Ikegawa
authors.forename: Asako
authors.initials: A
authors.lastname: Matsushima
authors.forename: Hiroshi
authors.initials: H
authors.lastname: Tanaka
authors.forename: Takeshi
authors.initials: T
authors.lastname: Shimazu
authors.forename: Hisashi
authors.initials: H
authors.lastname: Sugimoto
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001831:Body Temperature / Q000502:physiology; D001930:Brain Injuries / Q000150:complications*; D005260:Female; D015600:Glasgow Coma Scale; D006801:Humans; D006973:Hypertension / Q000209:etiology* / Q000628:therapy*; D007036:Hypothermia, Induced / Q000379:methods*; D007427:Intracranial Pressure; D007958:Leukocyte Count; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D014812:Vitamin K / Q000097:blood
chemical_list: D014812:Vitamin K