RECOGNITION

Initial assessment:

1. Assessment of the A, B and C should be made before moving on to D
2. Assess conscious level (ACVPU or GCS)
3. Examine pupils
4. Check blood glucose
5. Focused neurological examination
6. Look for signs of traumatic brain injury

The ACVPU scale and Glasgow Coma Scale (GCS) have been developed to quantify a patient’s conscious level. It is important to document one of them. The ACVPU scale is preferred in the RRAPID course due to it’s relative simplicity and is a component of the National Early Warning Score 2 (NEWS2). A patient’s conscious level can vary between being in a coma (Unresponsive on ACVPU scale, GCS 3) and alert, orientated (Alert on ACVPU scale, GCS 15 ).

ACVPU

ACVPU is a simpler and quicker alternative to the GCS where the patient scores A, C, V, P or U according to their response to stimulation. The benefit of this system is that it is clearly descriptive, giving an immediate understanding of the patient’s conscious level.

• A = Alert
• C = Confusion
• V = responds to Voice
• P = responds to Pain
• U = Unresponsive

Glasgow Coma Scale

The GCS is relatively easy to perform and is a simple grading system of a patient‘s level of consciousness. It was initially designed in Glasgow in 1974, for use in intensive care units on head injured patients. Scored from 3 (comatose) to 15 (alert and orientated). There are 3 component parts, Eyes, Verbal and Motor responses to stimulation. If any component part is affected by an interfering factor then the score is non testable (NT). For example a patient who is intubated cannot be tested for a verbal response. They would be scored as E₄V_NTM₆.

Assessment starts with a verbal stimulus to the patient (for example ‘Hello Mr X can you open your eyes for me?’). If the response is good, then further questioning will establish if there is any evidence of confusion and if the patient is following commands (e.g. moving fingers on command). If there is no response to a verbal stimulus then it will be necessary to assess response to pressure. Pressure is best placed in the supra-orbital notch. The supra-orbital notch is located in the supra-orbital margin (superior and medial edge of the orbit) and contains the supra-orbital nerve. The response to this pressure is assessed and most importantly the eye, verbal and motor score is noted. Where a patient has differing responses on their left and right sides it is their best score that is recorded. Serial measurement of the GCS is particularly useful to monitor patients at risk of deterioration and a drop in GCS should prompt a further assessment of the patient.

 Reference: https://www.glasgowcomascale.org/

Pupils

Examine the pupils and note the size, equality and reaction to light.

A fixed dilated pupil in the context of a brain injury indicates herniation of the temporal lobe through the tentorial hiatus (‘coning’) as a result of 3rd cranial nerve compression. Urgent discussion with a neurosurgical centre is required.

Bilateral fixed dilated pupils are a sign of brain death but can occur in deep unconsciousness due to drugs or hypothermia.

Pinpoint pupils are seen with an opioid overdose.

Blood glucose

Both hypo and hyperglycaemia can cause a reduction in consciousness. The blood glucose should be measured as part of your assessment of D. A rapid finger-prick bedside testing method can be used.

Focussed Neurological Examination

A brief neurological examination is required to rule out large cerebral ischaemic events and intracranial bleeds. The examination should be brief but assess tone and power in all limbs. Look for any asymmetry of spontaneous limb movement and check reflexes. The plantar responses are often both extensor in a coma of any cause.

Trauma

Reduced consciousness due to a traumatic head injury is usually evident from the history, however, you should always look for signs of trauma which may have been overlooked. Soft tissue damage such as bruising and swelling should be looked for particularly on the back of the head, which may be hidden from view. Leaking cerebrospinal fluid (CSF) from the nose or ear is indicative of a base of skull fracture. Typically an extradural haematoma presents with a reduction in consciousness after a delay, or a lucid period following a head injury.

Immediate management:

1. If GCS < 9 seek urgent senior support and anaesthetics review. Patient will require a secure airway such as an endotracheal tube.
2. Treat life threatening breathing and circulatory problems.
3. Treat reversible causes of reduced consciousness (e.g. low glucose, opioid overdose and seizures).
4. Consider further investigations such as a CT head, urine for toxicology, thyroid function tests or a lumbar puncture after excluding raised intra-cranial pressure.

An unconscious patient can be managed in the lateral recovery position as long as the A, B and C are adequate. This is to protect the airway in case of vomiting if the patient does not have a protected airway such as an endotracheal tube.

If the patient is unresponsive, GCS < 9 and the airway is at risk of compromise then an endotracheal tube is required. Call for anaesthetic help.

If the cause of reduced consciousness is not clear a CT head should be considered to rule out an intra-cerebral event.