Head injury: warning signs, assessment and recovery

Head injury, concussion and structural brain injury are not the same thing

A head injury can affect the scalp, skull, protective membranes, blood vessels or brain. Some impacts leave no structural brain damage. A contusion is bruised brain tissue; a haematoma is a collection of blood around or within the brain. Bleeding or swelling can raise pressure because the skull cannot expand.

Concussion is a clinical disturbance of brain function. It may cause headache, dizziness, nausea, tiredness, feeling slowed or foggy, sensitivity to light or noise, sleep or mood change, and difficulty with memory or concentration. Concussion can occur with a normal CT scan, while symptoms alone cannot identify a bleed.

What happens in the emergency department

• Immediate threats to breathing, circulation and the neck or other body areas are treated first.
• The team reconstructs the event and checks consciousness, pupils, speech, movement, sensation, balance and the person’s usual baseline.
• The Glasgow Coma Scale is one part of repeated neurological assessment; a number never replaces the whole examination.
• Age, symptoms, examination, the injury mechanism, medicines and the possibility of safe supervision all influence the next step.
• Depending on the findings, the safe path may be discharge with written advice, observation, CT, admission or transfer for specialist care.

CT, observation and what a normal scan means

CT is the first-choice emergency test for clinically important acute structural brain injury when age-appropriate criteria are met. Not every head impact needs a scan, and an online checklist cannot safely replace examination. MRI can answer selected later questions but is not usually the first emergency test for acute bleeding.

A normal CT is reassuring about the injuries it is designed to detect, but it does not rule out concussion or predict exactly how long symptoms will last. Observation and repeat neurological checks are important when symptoms, timing or risk make one assessment insufficient. New deterioration after discharge needs reassessment even after an earlier normal scan.

Medicines, children, older people and other factors that change risk

Anticoagulants and some antiplatelet medicines can change the decision about CT or observation. Do not stop, reverse or change these medicines yourself after an injury; give the clinician the exact medicine, dose and time last taken. A medicine that affects clotting increases concern, but it does not mean that bleeding has definitely occurred.

Children need age-specific examination, observation and imaging criteria. Older people may have a less obvious history after a fall, a different pre-injury level of function, fragile blood vessels or medicines that change risk. Adult rules must not simply be copied to children, and a person’s usual cognitive or neurological baseline matters at every age.

If discharged: the first 24 hours after the injury

• A suitable responsible adult should stay with the injured person until 24 hours after the injury and know the return-to-hospital warning signs.
• Follow the verbal and written discharge plan, including whom to contact if symptoms change. The plan should be age appropriate and accessible.
• Sleep itself is not prohibited after a clinician has judged discharge safe. Routine waking every two hours is not a substitute for supervision; follow the individual instructions and seek help if the person cannot be roused normally.
• Do not use alcohol, drive, return to contact sport or undertake hazardous activity until the recovery plan says it is safe. Do not start, stop or change medicines unless a clinician advises it.

Concussion recovery is gradual and individual

Many people improve steadily, but symptoms can fluctuate and may become more noticeable with physical or mental effort. A staged return to everyday activity, school, work, driving and sport should be guided by symptoms and professional advice rather than a fixed timetable.

Children may need temporary changes to school attendance, screen use, homework, physical education and sport. Adults may need adjustments to workload, travel, shift work or safety-critical tasks. Avoiding another head impact during recovery is important.

If symptoms do not settle

Persistent headache, dizziness, balance problems, sleep change, fatigue, slowed thinking, memory or concentration difficulty, mood change, loss of confidence or reduced function deserve review. Worsening or new neurological symptoms require urgent reassessment rather than waiting for a routine appointment.

Longer-lasting problems are not always primarily neurosurgical. Depending on the pattern, useful care may involve primary care, neurology, neuropsychology, clinical psychology, vestibular or physical therapy, pain expertise, paediatrics, occupational support or a multidisciplinary neurorehabilitation team.

Severe brain injury, intensive care and the neurosurgical role

Brain Trauma Foundation guidance applies to severe traumatic brain injury treated by trauma, intensive-care and neurosurgical teams; it is not a home-triage or ordinary-concussion guide. Hospital care aims to prevent secondary injury by supporting oxygen delivery and circulation and, where indicated, monitoring and treating pressure inside the skull.

Care can include ventilation, intensive neurological monitoring, medication, drainage of cerebrospinal fluid and surgery. Neurosurgery may evacuate a pressure-producing haematoma, treat selected depressed skull injuries or cerebrospinal-fluid leaks, or create space for dangerous pressure that has not responded to other care. These are conditional specialist decisions based on the examination, scans, timing, clotting status and the whole clinical situation—not automatic steps after every abnormal scan.

Questions worth taking to follow-up

• What injury has been found, and what remains uncertain?
• Which symptoms should trigger emergency reassessment rather than a routine appointment?
• Do my medicines change the imaging, observation or follow-up plan?
• How should I return to school, work, driving, exercise and sport?
• Who should review persistent symptoms, and what rehabilitation or practical support may help?