Acute and subacute brain injury

Phase one — hours to days: systemic management

This is where most of the eventual outcome is determined, and almost none of it involves anything on the rest of this site. Part of the injury happened at the moment of the event and cannot be undone. The other part — secondary injury — develops over the hours and days that follow, and that part is modifiable.

Intensive care in this phase is directed at keeping the injured brain in conditions it can survive: adequate blood pressure and cerebral perfusion, controlled oxygen and carbon dioxide, avoidance of fever, stable glucose and sodium, control of intracranial pressure, and detection of seizures — which after a severe injury are frequently non-convulsive and visible only on EEG monitoring.

• Temperature. Fever worsens injured brain tissue and is actively prevented. Therapeutic cooling is established treatment in newborns with moderate to severe hypoxic-ischaemic encephalopathy; in older children after cardiac arrest, trials have not shown an advantage over carefully maintained normal temperature, but avoiding fever remains standard.
• Seizures. Non-convulsive seizures and status epilepticus are common after severe injury and are missed without EEG monitoring. They are treatable.
• Nutrition. Started early rather than deferred. Adequate protein and energy during this period is associated with better outcomes and is frequently under-delivered.
• The cause-specific treatment. Immunotherapy in autoimmune encephalitis, reopening the vessel in selected childhood stroke, surgery where a mass or bleed requires it. This is the point at which the diagnosis is worth more than any other intervention discussed on this site.

Phase two — weeks: rehabilitation begins in intensive care

Rehabilitation is not something that starts after discharge. In the subacute phase it starts in the intensive care unit, and what is done there determines how much of the later work is recovery rather than repair of avoidable secondary problems.

• Positioning and tone. Contractures form quickly in an immobile child with rising tone, and they are far easier to prevent than to treat. Positioning, splinting and early tone management belong in this phase.
• Early mobilisation. Getting a child upright and moving as soon as it is safe is associated with better functional outcomes, and the evidence for it in paediatric intensive care has strengthened.
• Swallowing and nutrition. Swallow safety is assessed rather than assumed; silent aspiration is common after brain injury and is a frequent cause of readmission.
• Communication. A child who cannot speak needs a route to communicate from the beginning, not once speech has been judged unlikely to return.
• The family. Parents in this phase are themselves in an acute situation. Practical support and honest information are part of the treatment, not an adjunct to it.

From this point the principles are the same as everywhere else in rehabilitation: active, goal-directed, task-specific practice, repeated often enough to matter. Conventional care →

Phase three — months and years: where supportive treatments sit

This is the phase in which most families begin asking about cell therapies, exosomes, Muse cells and stimulation, and it is worth being precise about how the evidence maps onto it.

Most research in acquired injury has targeted the acute and subacute window — the period in which inflammation is active and tissue is still being lost. That is where the biological rationale is strongest and where most registered trials recruit. Families, however, usually arrive at these questions months or years later, in the chronic phase, where the rationale is different and the evidence is thinner.

That mismatch is the single most useful thing to understand before paying for a chronic-phase course. It does not mean nothing can help later; it means the published results being cited were often produced in a different phase of a different illness.

What can reasonably be said about recovery

Recovery after acquired brain injury in childhood is slower than families are led to expect and continues for longer than is often stated. Meaningful change is still seen well beyond the first year, particularly where active rehabilitation continues.

At the same time, early prognosis is genuinely uncertain, and both excessive pessimism and excessive optimism in the first weeks are common and unhelpful. A clinician who says plainly that it is too early to know is usually being accurate rather than evasive.