Randomised Evaluation of Surgery with Craniectomy for patients Undergoing Evacuation of Acute Subdural Haematoma

Research summary

Head injury is common with approximately 900,000 people attending Emergency Departments per year in the UK. The majority of patients sustain a mild Traumatic Brain Injury (TBI). However, the majority of fatal and unfavourable outcomes occur in patients with moderate or severe TBI, which account for approximately 10% of attenders. An estimated 1.2 million people live with some level of TBI-related disability in the UK, which has profound socio-economic consequences, as the prevalence is particularly high among children and young to middle-aged adults.

By far, the most important early consequence of TBI is the development of an intracranial haematoma (also known as a clot). Intracranial haematomas can be extradural (inside the skull but outside the dura mater which is the outermost covering of the brain), subdural (between the dura mater and the brain), intraparenchymal (within the brain) or a combination thereof. Without effective surgical management, an intracranial haematoma may transform an otherwise benign clinical course with the expectation of recovery, to a situation where death or severe disability will occur.

Studies conducted after the introduction of CT scanning report an incidence of acute subdural hematoma (ASDH) between 12 and 29% in patients admitted with severe TBI. Studies looking at patients with ASDH requiring surgery quote mortality rates between 40 and 60%. The decision to operate on an ASDH is usually based on the patient’s GCS score, pupillary exam, comorbidities, CT findings, age, and, in delayed decisions, ICP. Neurological deterioration over time is also an important factor influencing the decision to operate. Different surgical techniques have been advocated for the evacuation of an ASDH. Patients with an ASDH that require an operation to remove the clot are currently treated either with a craniotomy or a decompressive craniectomy (DC). The choice of operative technique is influenced by the surgeon’s expertise, training, and evaluation of the particular situation. Some centres treat all SDH with decompressive craniectomies, whereas other centres used solely craniotomies.

The two health technologies we wish to assess are the two most widely used surgical techniques for the evacuation of an ASDH: craniotomy and decompressive craniectomy (DC). The difference between these 2 procedures is that a bone flap is left out prior to closing the skin in DC. The advantage of a DC is that it is effective in controlling brain swelling which is often a problem in the days after the operation. When the swelling goes down, the patient has another operation to reconstruct the skull (cranioplasty). The advantage of a craniotomy is that the patient will not need a later operation to rebuild the skull. However, it may fail to control brain swelling in some patients.

Five-year pilot data from an NHS neurosurgical unit (Cambridge) show that 56% of patients with ASDH were treated with a DC. In this retrospective cohort comparison study, 91 patients had an operation for an ASDH. The standardised morbidity ratio was lower in individuals who received DC (0.75; 95% CI 0.51–1.07) than in those treated with a craniotomy (0.90; 95% CI 0.57–1.35). Although the standardised morbidity ratio 95% confidence intervals overlap, this study lends support to the hypothesis that DC may lead to better functional outcomes in comparison to craniotomy for adult head-injured patients with ASDH.

There is currently no high-quality evidence guiding surgeons as to which operation they should be offering as first line treatment to patients with ASDH. The results of a high-quality study will be used to inform future NICE head injury guidelines and the practice of neurosurgeons in the NHS and worldwide. We aim to perform a multi-centre, pragmatic, parallel-group randomised trial in order to compare the clinical and cost-effectiveness of decompressive craniectomy versus craniotomy for the management of adult head-injured patients undergoing evacuation of an acute subdural haematoma.

Main inclusion criteria

  1. Adult head-injured patients (>16 years)

  2. Acute subdural haematoma on CT

The admitting neurosurgeon feels that the haematoma needs to be evacuated with a large bone flap (recommended size ≥11 cm anteroposterior diameter) either by a craniotomy or decompressive craniectomy*

*Patients with additional lesions (e.g. intracerebral haemorrhage, contusions) can be included

Main exclusion criteria

The presence of any of the following will preclude patient inclusion:

  1. Bilateral acute subdural haematomas both requiring evacuation

  2. Previous enrolment in the RESCUE-ASDH study

  3. Severe pre-existing physical or mental disability or severe co-morbidity which would lead to a poor outcome even if the patient made a full recovery from the head injury

Chief investigator

Prof Peter Hutchinson

Contact details

Clinical Trials Coordinator: Carol Davis-Wilkie

Telephone: 01223 254921 | Email: [email protected]