Chapter 24 Neurological emergencies
COMA OR IMPAIRED CONSCIOUSNESS
Impaired consciousness is recognised and described by observation of response to sound, light, touch or painful stimulus. The Glasgow Coma Scale (GCS) gives a standard way of recording and monitoring the level of consciousness (see Chapter 15, ‘Neurosurgical emergencies’).
Examination
• Look for signs of:
• raised intracranial pressure (hypertension, bradycardia with dilated and non-reactive pupil is classical, see Chapter 15)
• Pupils: enlarged pupil with impaired response to light signifies a third nerve lesion. This can alert to transtentorial herniation. When bilateral, it suggests brainstem death. Small pupils occur with pontine lesions or opiate effect. Dilated pupils can be due to effect of psychostimulants.
• Eye movements: test by following a target or reflex with head turning (oculocephalic reflex). Failure of conjugate gaze to the side of the hemiplegia is common with a hemisphere lesion. When severe, the head and eyes stay deviated away from the hemiplegic side. Dysconjugate gaze is indicative of lesions of the 3rd, 4th and 6th cranial nerves or their nuclei or connections in the brain stem.
• Fundoscopy: look for papilloedema which usually indicates raised intracranial pressure. Preretinal haemorrhage, which may have a fluid level, suggests subarachnoid haemorrhage (SAH). Hypertensive or diabetic retinopathy may be present.
Investigations
• Blood count, blood sugar level (BSL), electrolytes, urea, creatinine (EUC), liver function tests (LFTs) and calcium
• If sepsis is suspected: blood and urine culture; lumbar puncture should only be performed if there are no contraindications (see ‘Lumbar puncture’, below)
Management
EPILEPSY
Fits are usually self-limiting and no urgent drug treatment is needed. During fits:
2. Observe the features and duration of the fit: rigid (tonic) or jerking (clonic) or focal (arm, leg, face, eyes, lips etc), responsiveness, breathing, pallor, cyanosis, frothing, incontinence, eyes open or deviated, vocalisation etc. Classification as generalised or partial will influence management. Pseudoseizures are common and are often hard to recognise.
4. Do not put anything between the teeth during a fit. Damage to the patient’s teeth or the carer’s fingers is more likely than any benefit.
After the fit, ask if there is a history of fits.
Prolonged fitting or frequent fitting (status epilepticus)
Partial seizures may be prolonged or frequently recurrent without major hazard.
Major generalised seizures lasting more than 5–10 minutes or recurring rapidly are life-threatening. This situation demands prompt and adequate IV drug therapy, monitoring and support.
Treatment
2. Give midazolam 2.5 mg IV with repeated bolus doses up to 15 mg (0.2 mg/kg for a child). Buccal or intranasal administration can be used if venous access is delayed. May have been given by carers before reaching the emergency department. Alternatives to midazolam are:
3. Add phenytoin 17 mg/kg IV at no more than 50 mg/minute (if not already taking phenytoin). For a child, administer 20 mg/kg IV at no more than 25 mg/minute.
4. Clonazepam 0.5 mg 8-hourly (oral or parenteral) for the next 24–48 hours may permit initiation of long-term oral anticonvulsant medication.
5. If seizures persist despite treatment, anaesthetise with thiopentone and muscle relaxant, provide ventilatory support and admit to intensive care unit. Prolonged seizures can result in damage to the brain and other organs with significant increase in mortality.
CEREBROVASCULAR DISEASE
Initial assessment and management of stroke
• excluding stroke mimics, e.g. seizure, hypoglycaemia, sepsis, syncope, drug overdose, hypoxia, hyponatraemia and hemiplegic migraine
• identifying any cardiovascular abnormalities, e.g. atrial fibrillation (AF), signs of endocarditis, carotid bruit/dissection
Investigations
• Perform non-contrast CT scans, full blood count (FBC), electrolytes, creatinine, blood glucose level, coagulation studies, urinalysis, ECG and chest X-ray.
• Initial CT scans can be normal for ischaemic stroke as infarction is best shown a few days after the onset. Early CT is used to exclude haemorrhage or brain tumour to allow the commencement of antiplatelet or thrombolytic agents.
• Magnetic resonance imaging (MRI) and magnetic resonance angiography can replace CT scans and carotid ultrasound when available. MRI shows infarction immediately after a stroke and can distinguish a new from an old infarct. Small lesions and brainstem lesions invisible in CT scans can be seen with MRI.
Stroke management checklist
• Neurological status: hourly GCS and neurological observation for first 4 hours or until stabilised.
• Body temperature: control fever at < 37.5°C with paracetamol orally or rectally. Septic work-up if fever > 38°C.
• Blood glucose: aim for 5–11 mmol/L. If BSL < 3 mmol/L, give 50% dextrose. If BSL > 11 mmol/L, start SC or IV insulin.
• Blood pressure: established drug treatment for hypertension should be continued. Avoid new antihypertensive drug therapy during the first 24 hours as it may worsen the ischaemia. However, treatment is indicated by systolic blood pressure (SBP) > 220 mmHg or diastolic blood pressure (DBP) > 120 mmHg or hypertensive encephalopathy, acute myocardial infarction (AMI) or acute left ventricular failure (LVF).
• Swallowing status/hydration: until it is established that swallowing is safe a ‘nil by mouth’ order is applied. IV fluids without glucose are given to correct dehydration at presentation and provide maintenance fluid and electrolytes. Planning of oral intake or IV or nasogastric fluids and feeding needs daily review.
• Urine output: bladder catheterisation may be needed to monitor urine output and assist nursing care of pressure areas.
Stay updated, free articles. Join our Telegram channel
Full access? Get Clinical Tree
