• Paediatric Cerebral Performance Category (PCPC) at 12 months after injury [ Time Frame: 12 months ] [ Designated as safety issue: Yes ]
  
• Recruitment Rates [ Time Frame: Recruitment completion ] [ Designated as safety issue: No ]
  
• Adverse Events [ Time Frame: Recruitment completion ] [ Designated as safety issue: Yes ]
  

• Intracranial pressure(ICP)/Cerebral perfusion pressure(CPP) control [ Time Frame: Recruitment completion ] [ Designated as safety issue: Yes ]
  
• Duration of mechanical ventilation [ Time Frame: Recruitment completion ] [ Designated as safety issue: Yes ]
  
• Intensive care and hospital length of stay [ Time Frame: Recruitment completion ] [ Designated as safety issue: Yes ]
  
• Neuropsychological Outcome [ Time Frame: 12 months ] [ Designated as safety issue: Yes ]
  

Procedure: Induced Hypothermia
Induced Hypothermia within 6 hours of injury and maintained for a minimum of 72 hours

We propose to do a pilot study of 50 children admitted with severe TBI to paediatric intensive care units in Australia and New Zealand. Severe TBI will be defined as children with either (i) Glasgow Coma Scale (GCS) ≤ 8 and an abnormal CT scan or (ii) motor score of ≤ 3 and normal CT scan. Children will be included only if they can be randomised within 6 hours of the injury occurring. Patients will be stratified a priori by (i) centre and (ii) Glasgow Coma Score. One half will be cooled to 32-33°C for 72 hours and then slowly rewarmed. If intracranial hypertension occurs during or after rewarming, the hypothermia group will have cooling continued until intracranial pressure (ICP) is controlled. The other half will have their temperature maintained at 36-37°C. All other aspects of care will be managed with a standardised protocol.

The purpose of this pilot study is to establish the feasibility of doing an outcome study with other international centres. It will also assess the safety of more prolonged cooling and protocol adherence. Primary outcomes will be the frequency of adverse events related to hypothermia, recruitment rates and protocol adherence. These children may also be able to be included in a larger trial.

The primary aim of the outcome study will be to determine whether, in children with severe TBI, prolonged initial hypothermia improves the proportion with good outcome 12 months after injury when compared to initial normothermia. Outcome will be assessed at 6 and 12 months. The primary outcome measure will be a Paediatric Cerebral Performance Category (PCPC) at 12 months after the date of injury, dichotomized to poor outcome (categories 4-6) and good outcome (categories 1-3). Secondary outcome measures will be (i) PCPC at 6 after injury (ii) standardised tests (intelligence and memory, functional outcome, attention, executive functions) 12 months after injury (iii) ICP and cerebral perfusion pressure (CPP) during the first 5 days of treatment (v) frequency and nature of interventions to control ICP/CPP (vi) duration of mechanical ventilation and (vii) potential adverse events.