Approach to the comatose patient Stephen Lo

Introduction Focus on developing a structured approach to coma Can be also applied to exam questions

Case 50 year old polynesian lady presented with headache followed by LOC How would you assess and manage this patient?

Investigations

My approach Initial management Differential diagnosis Investigations Management

Initial steps: safety + ensure adequate resources Ask for resources ABC, basic resuscitation

Assessment of airway, breathing, and circulation Airway patency Airway protection: What is the GCS Is there protective reflexes present What is the risk of aspiration Are there secretions Rate and pattern of ventilation Circulation: signs of shock, hypotension. Consider maintaining CPP. In this case, I would put Blood sugar levels at the priority of the ABCs

Differential diagnosis Need to construct a list of differential diagnosis at this point.

Approach to the diagnosis Need a simple way of classifying causes Intracranial Extracranial

Intracranial Consider surgical sieve or other pneumonics Need to include the key ones such as: bleed, stroke, infection, trauma, Seizures, rarer causes such as tumours, autoimmune, vasculitis, PRES context specific differentials such as vasospasm, hydocephalus in SAH

Extracranial These are generally metabolic in nature. Again, have a sieve that you are familiar with, but need to include the most common ones including: Drugs: direct effect, indirect effects Acid base Hypoxia/hypercarbic Temperature Organ function: Kidney and liver Nutritional Electrolyte disturbance Endocrine Sepsis

Mimics of coma Severe peripheral neuropathy Guillain Barre syndrome Botulism Critical illness neuropathy Locked in syndrome Akinetic mutism

Assessment History and examination to rule out or in your differentials Catagorize into three broad categories based on patient’s signs Coma with focal signs: Suggests an intracranial event Coma with meningism: Suggests meningitis, SAH Coma without signs: Suggests a very diffuse intracranial lesion or an extracranial cause

Investigations Consider all your options Systemic investigations CT head Lumbar puncture: MCS, PCR, antibodies CT angiogram EEG MRI SSEPs Cerebral angiogram

What’s your management now? Medical management Specific management Position of patient, CO2 control, BP control, Osmotherapy, sedation, sugar, seizure control, temperature General management Interventions Radiological interventions Surgical management

Case 2 49 yo male thai chef that was found collapsed at home, brought in by ambulance. How would you manage this patient?

Assessment ABC: Noisy breathing GCS: E1V2M5 Sats: 84 % on 6L BP 190/80, HR 90/min

Further clinical assessment Right side movement less than left Pupils equal and reactive

Investigations

Finding underlying causes Thromboembolic Consider source of clot Bleeding Is there an underlying abnormality Infection Are there underlying structural abnormality or immunosuppression Epilepsy Adult onset always need to consider cause

Further investigations ASD on echo Paradoxical embolus and therefore infarct

Other learning points That an extensive unilateral lesion can also cause reduced LOC