Neurosurgeons and Traumatic Brain Injury

In the first article of this series, we explored the non-surgical acute management of traumatic brain injury (TBI). This follow-up delves into the neurosurgical perspective, highlighting both the surgical decision-making process and the essential role neurosurgeons play as part of the multidisciplinary team. As emphasised before, “interdisciplinary team working must be the cornerstone of treatment in this very vulnerable patient group.” Neurosurgeons are central to this collaborative approach.

Once a TBI patient is stabilised by the pre-hospital and emergency teams, neurosurgical consultation often follows. The on-call neurosurgeon typically reviews initial scans and offers urgent input.

Whilst it is a commonly held belief that neurosurgeons are binary decision-makers – ‘yes’ or ‘no’, in answer to the question, “is there a role for neurosurgical intervention?” – in fact, the route to that decision-making is often incredibly complex.

There are a number of pieces of information that need to be collated and considered in a very short period of time, in order to reach a conclusion about the optimal management for an individual patient.

Very often, the decision not to intervene is a harder one to reach, than a decision in the affirmative.

The factors that are considered include:

  • Severity of the TBI – based on the clinical status of the patient, together with imaging findings
  • The presence of other injuries – the polytrauma patient
  • Patient pre-existing comorbidities, performance status, and their wishes
  • Whether a patient can be safely managed locally (the majority of TBI cases can remain at their local hospitals without neurosurgical presence)
  • The level of ward care required (HDU/ICU), and the need for airway protection for transfer (intubation and ventilation, by definition determining the need for an ICU bed)

For those patients in whom surgery may be indicated, time critical action is required to preserve life and neurological function. The phrase “Time is Brain” coined by the stroke fraternity, is equally applicable in severe TBI, with the goals of surgical intervention being twofold:

  1. Minimise the damage from the primary brain injury – which is immediate and irreversible
  2. Prevent secondary brain injury – which arises from a number of physical, biochemical, and cerebrovascular changes following the primary insult

Types of Neurosurgical Injuries and Indications for Surgery

Extradural Haematoma (EDH)
EDHs are collections of blood between the inner skull and the dura mater. Most often, they result from arterial bleeding, typically following trauma that fractures the skull in the region of the pterion, and lacerates the middle meningeal artery. These injuries frequently affect younger adults after assaults, falls, or road traffic accidents.

Classic teaching describes the “lucid interval” – a temporary recovery of consciousness before rapid neurological decline. Because patients can appear deceptively stable, close observation and rapid rescanning are essential.

Surgical evacuation is indicated if the haematoma exceeds 30 cm³, or if there are signs of raised intracranial pressure or neurological deterioration. EDH accounts for 2.7–4% of all TBI cases, with adult mortality rates near 10% [1]. The prognosis, however, is favourable when treated early, as the underlying brain is often relatively uninjured.

Acute Subdural Haematoma (ASDH)
ASDHs involve bleeding between the dura and the surface of the brain. In younger individuals, they often follow high-energy trauma with associated brain contusions; in the elderly, they frequently result from minor falls that tear fragile bridging veins in the context of cerebral atrophy.

The decision to operate is based on several radiological and clinical criteria:

  • Haematoma >10 mm in thickness
  • Midline shift >4-5 mm
  • GCS decline of ≥2 points from injury to hospital
  • Pupillary abnormalities

Mortality rates for ASDHs requiring surgery range from 15% to 60%, depending heavily on age and physiological reserve [2]. Careful case-by-case assessment is vital, particularly when deciding intervention in older patients. Such patients may tolerate a larger volume subdural haematoma due to pre-existing brain atrophy, and the risks of surgery often outweigh benefit in the acute setting. Outcomes following craniotomy for evacuation of acute subdural haematoma in patients over the age of 60 are poor [2]. If the patient survives, then over time (days – week) the acute blood (jelly-like consistency) becomes chronic (less viscous) and burr-hole drainage (a simpler, less risky, operation – which may even be performed under local anaesthetic) may be beneficial.

Assessing the degree of underlying brain damage is also important in considering outcomes following acute subdural haematoma – contrary to the extradural haematoma which frequently has little underlying parenchymal damage, ASDH is often associated with significant traumatic injury to the brain – adversely impacting on the potential clinical recovery for the patient.

The RESCUE-ASDH trial explored whether a craniotomy (replacing the bone flap) or decompressive craniectomy (leaving the bone out) offered better outcomes. It found no significant difference in functional or quality-of-life outcomes between the two [3], though surgical strategy often depends on the extent of swelling and institutional practice. Replacing the bone flap has the advantage that a cranioplasty is not required.

Traumatic Intracerebral Haematoma (ICH) and Contusions

Traumatic contusions – bruises of the brain tissue – commonly occur in the frontal and temporal lobes, particularly on the basal surfaces. These lesions can evolve over time, enlarging as surrounding oedema develops, sometimes called the “blossoming” phenomenon.

Most ICHs are treated conservatively unless they:

  • Cause significant mass effect
  • Are associated with declining neurological function
  • Result in refractory raised ICP

Surgical evacuation may be considered when:

  • GCS 6–8 with haematoma volume >20 cm³
  • Midline shift >5 mm
  • Cisternal compression present on CT

Due to their diffuse and evolving nature, contusions may require serial imaging and close observation, especially when patients cannot be assessed neurologically due to sedation or intubation.

Diffuse Brain Injury, ICP Monitoring, and CSF diversion

In patients with coma but without obvious mass lesions, the challenge becomes monitoring and managing diffuse brain injury – such as traumatic subarachnoid haemorrhage, contusions, or widespread cerebral oedema.

In these scenarios, intracranial pressure (ICP) monitoring becomes essential (a pressure probe is placed ~2cm deep into the brain, through a metal bolt secured into the skull). It serves as a proxy for assessing the state of the brain when clinical examination is limited. Where resources allow, brain tissue oxygenation (PbtO₂) monitoring may also be used to guide treatment, although it is not yet standard practice. The physiological rationale underlying ICP management is to preserve oxygen delivery to the brain, and yet studies have shown that cerebral hypoxia is common; thus, the notion that multimodal monitoring to include PbtO₂ might allow refinement of clinical management and improve outcomes compared to ICP management alone.

Several major trials are evaluating the role of multimodal monitoring:

  • OXY-TC [4] – Multi-centre, randomised controlled superiority trial; to evaluate the superiority of combined ICP + PbtO₂ over ICP alone to reduce the proportion of patients with poor outcomes at 6 months; study completed and found no reduction; also had technical failures associated with the intracerebral catheter
  • BOOST [5] – Multi-centre, randomised, comparative effectiveness study; to determine whether a treatment protocol, informed by PbtO₂ plus ICP, results in improved neurological outcome (GOSE) 6 months post-injury compared with ICP alone; study ongoing at time of publication
  • BONANZA [6] – Multi-centre, definitive intervention study of neuro-intensive care management of early brain tissue oxygen optimisation; to assess the value of combined ICP/ PbtO₂ monitoring together with specific set of interventions to be instituted when brain oxygen levels low on mortality and disability; study ongoing at time of publication

Treatment is guided by established ICP management protocols [7, 8]. If ICP remains high despite maximal medical therapy, drainage of cerebrospinal fluid (CSF) may be indicated, with surgical decompression being the final option, as per the Brain Trauma Foundation guidelines.

CSF diversion can be achieved with the use of either an external ventricular drain (EVD) or lumbar drain (LD). ICP can be measured using the EVD, and CSF drainage can then be regulated through intermittent volume-controlled drainage, by continuous pressure controlled drainage, or a combination. Whether CSF diversion strategies avoid the need for further escalation to surgical decompression, or reduces the morbidity/mortality is not clear [9, 10]. There has been no multi-centre, prospective trial to assess if CSF diversion reduces the need for decompressive craniectomy.

Decompressive Craniectomy: A Last Resort

When all else fails to control dangerously high ICP, decompressive craniectomy (DC) may be lifesaving. The skull is removed, and the dura is opened to allow the brain to swell safely.

Two landmark trials inform this practice:

  • DECRA (2011): Early bifrontal DC reduced ICP and ICU stay but was linked with worse neurological outcomes [11]
  • RESCUEicp (2016): DC reduced mortality in patients with refractory ICP but there was an increased number of survivors with severe disability or in a vegetative state [12]. However, at 24 months, there was an improvement in the quality of life of the surgical patients as opposed to the medical patients such that DC saved 21 lives / 100 with two thirds independent inside/outside the home and one third dependent [13].

It is important to acknowledge that these trials recruited patients between the ages of 10-65 (DECRA median age 24, RESCUEicp mean age 33); younger patients have the capacity to improve over time, with greater physiological reserve from the onset of injury; the outcome for older patients is less well known and is unlikely a simple extrapolation of the data available thus far.

Decompressive craniectomy is probably one of the most contentious areas in neurosurgery. The findings from these trials highlight the ethical complexities of neurosurgical decision-making. Families and clinicians must weigh survival against quality of life.

Long-Term Surgical Sequelae: Hydrocephalus and Cranioplasty

Post-traumatic hydrocephalus (PTH), whilst an infrequent long-term complication of TBI (2% of all TBI patients admitted to intensive care [14]), can develop due to altered cerebrospinal fluid dynamics, requiring CSF diversion procedures like ventriculoperitoneal shunting.

Factors associated with an increased risk of its development include [14]:

  • Increasing age
  • Midline shift > 5 mm and traumatic SAH (subarachnoid haemorrhage) on the admission CT head scan
  • The need for EVD or DC

It is associated with permanent disability, so is important to be identified and treated.

Patients who undergo decompressive craniectomy may eventually need cranioplasty – surgery to reconstruct the skull. Despite being a technically ‘simple’ operation, it carries significant risks including infection, bleeding, seizures, and hydrocephalus; with rates of complication between 10 – 40%.

Optimal timing and materials for the cranioplasty plate remain uncertain. Some studies suggest early cranioplasty (<90 days) improves symptoms of “syndrome of the trephined” (cognitive and motor decline post-DC) [15], but others suggest the rate of hydrocephalus may increase [16]. Whilst international expert groups have published consensus statements, there remain no clear guidelines for timing of cranioplasty surgery or favoured material [17, 18].

As with all aspects of TBI care, decisions must be individualised, often involving input from neurosurgeons, neurologists, rehabilitation specialists, and families.

Multidisciplinary Teamwork: A Cornerstone of TBI Care

Modern TBI care demands seamless coordination across disciplines to deliver optimal care to the patient, and their family. The neurosurgeon’s role must, therefore, extend beyond the operating theatre.

In practice, this includes:

  • Liaising with major trauma and intensive care teams
  • Supporting neurology, neurorehabilitation, and neuropsychiatry
  • Working with therapy teams
  • Training and educating colleagues across all specialties

Strong communication also extends beyond the major trauma centre; with neurosurgeons building relationships across the regional network, providing support, training, and helping develop services.

Patients and their families must remain at the centre of our work. Clear, consistent communication and open discussion with families are essential to managing expectations effectively. Care must be taken to avoid mixed messages between teams, particularly ICU and neurosurgery, to ensure families are fully supported throughout what is often a long and complex journey for their relative.

Feedback from patients and their families should be actively sought, with their perspectives on potential improvements to current care settings and service design listened to and acted upon.

Integrated multidisciplinary working improves patient flow, decision-making, and outcomes – particularly important in time-sensitive and resource-limited settings.

Research: Driving Innovation in TBI

Neurosurgical practice in TBI is increasingly informed by robust clinical research. Current areas of research include, but are not limited to:

  • Improving diagnosis with new imaging techniques/clinical criteria
  • Optimising surgical interventions
  • Pragmatic trials of daily practice issues – such as the safe resumption of anticoagulant therapies following intracranial haemorrhage [19] and seizure management [20]
  • Understanding the complex mechanisms of brain injury and repair (neuroplasticity)
  • Identifying (and understanding the application of) biomarkers as indicators of injury severity, prognosis and treatment response

Research platforms such as TBI-REPORTER (https://tbi-reporter.uk) have been established to centralise and utilise data, with the aim to accelerate progress in clinical care.

These research efforts are fostering global collaboration between neurosurgery, emergency medicine, neurology, basic sciences, and sports and military medicine.

Conclusion

TBI is one of the most complex and challenging conditions in medicine. The neurosurgical role – critical though it is – represents just one part of a patient’s journey.

Every patient brings unique circumstances, values, and potential for recovery. As such, neurosurgeons must not only interpret scans and perform life-saving surgery, but also engage in compassionate, ethical, and collaborative decision-making.

As we continue to build evidence, expand research, and refine interdisciplinary pathways, we must hold fast to one guiding principle: working together offers patients the best chance at meaningful recovery.

References

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  2. Manivannan S, et al. Acute subdural haematoma in the elderly: to operate or not to operate? A systematic review and meta-analysis of outcomes following surgery. BMJ Open, 2021; 11:e050786 https://doi.org/10.1136/bmjopen-2021-050786
  3. Hutchinson PJ, et al. Decompressive Craniectomy versus Craniotomy for Acute Subdural Hematoma, New England Journal of Medicine, 2023; 388 (24):2219-2229 https://doi.org/10.1056/NEJMoa2214172
  4. Payen JF, et al. Intracranial pressure monitoring with and without brain tissue oxygen pressure monitoring for severe traumatic brain injury in France (OXY-TC): an open-label, randomised controlled superiority trial. Lancet Neurology, 2023; 22(11):1005-1014 https://doi.org/10.1016/S1474-4422(23)00290-9
  5. Bernard F, et al. Brain Oxygen Optimization in Severe Traumatic Brain Injury (BOOST-3): a multicentre, randomised, blinded-endpoint, comparative effectiveness study of brain tissue oxygen and intracranial pressure monitoring versus intracranial pressure alone. BMJ Open, 2022 Mar 10;12(3):e060188 https://doi.org/10.1136/bmjopen-2021-060188
  6. Brain Oxygen Neuromonitoring In Australia and New Zealand Assessment Trial – The BONANZA Trial; Australian New Zealand Clinical Trials Registry: ACTRN12619001328167P
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  9. Moyer JD, et al. External ventricular drainage for intracranial hypertension after traumatic brain injury: is it really useful? European Journal of Trauma and Emergency Surgery, 2023 Jun;49(3):1227-1234. https://doi:10.1007/s00068-022-01903-4
  10. Dagod G, et al. Impact of lumbar cerebrospinal fluid drainage to control intracranial hypertension in patients with severe traumatic brain injury: a retrospective monocentric cohort. Critical Care, 2025 Jan 2;29:2. https://doi:10.1186/s13054-024-05199-1
  11. Cooper DJ, et al. Decompressive Craniectomy in Diffuse Traumatic Brain Injury, New England Journal of Medicine, 2011; 364(16):1493-502 https://doi.org/10.1056/NEJMoa1102077
  12. Hutchinson PJ, et al. Trial of Decompressive Craniectomy for Traumatic Intracranial Hypertension, New England Journal of Medicine, 2016; 375(12):1119-30 https://doi.org/10.1056/NEJMoa1605215
  13. Kolias A, et al. Evaluation of outcomes among patients with traumatic intracranial hypertension treated with decompressive craniectomy vs standard medical care at 24 months: a secondary analysis of the RESCUEicp randomized clinical trial. JAMA Neurology, 2022; 79 (7):664-671 https://doi.org/10.1001/jamaneurol.2022.1070
  14. Lindfors M, et al. Incidence and risk factors of posttraumatic hydrocephalus and its association with outcome following intensive care unit treatment for traumatic brain injury: a multicenter observational study. Journal of Neurosurgery, 2023; 139(5):1420-1429 https://doi.org/10.3171/2023.2.JNS22728
  15. Ashayeri K, et al. Syndrome of the trephined: a systematic review. Neurosurgery, 2016;79(4):525-534 https://doi.org/10.1227/NEU.0000000000001366
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  19. Restart tICrH: A Randomised Trial of Timing to Restart Direct Oral Anticoagulants after Traumatic Intracranial Haemorrhage; Clinical trial identifier: NCT06322953
  20. MAST – Pharmacological management of seizures post traumatic brain injury; Clinical trial identifier: NCT04573803