Approach to the comatose patient

Stephen Lo

Introduction

Focus on developing a structured approach to comaCan be also applied to exam questions

Case50 year old polynesian lady presented with headache followed by

LOCHow would you assess and manage this patient?

Investigations

My approachInitial managementDifferential diagnosisInvestigationsManagement

Initial steps: safety + ensure adequate resources

Ask for resourcesABC, basic resuscitation

Assessment of airway, breathing, and circulation

Airway patencyAirway protection:

What is the GCS Is there protective reflexes presentWhat is the risk of aspirationAre 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 diagnosisNeed to construct a list of differential diagnosis at this point.

Approach to the diagnosisNeed a simple way of classifying causesIntracranialExtracranial

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 comaSevere peripheral neuropathy

Guillain Barre syndromeBotulismCritical illness neuropathy

Locked in syndromeAkinetic mutism

AssessmentHistory and examination to rule out or in your differentialsCatagorize into three broad categories based on patient’s signsComa 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 managementSpecific managementPosition of patient, CO2 control, BP control, Osmotherapy, sedation,

sugar, seizure control, temperatureGeneral managementInterventionsRadiological interventionsSurgical management

Case 249 yo male thai chef that was found collapsed at home, brought

in by ambulance.How would you manage this patient?

AssessmentABC: Noisy breathingGCS:

E1V2M5Sats: 84 % on 6LBP 190/80, HR 90/min

Further clinical assessmentRight side movement less than leftPupils equal and reactive

Investigations

Finding underlying causesThromboembolic

Consider source of clotBleeding

Is there an underlying abnormalityInfection

Are there underlying structural abnormality or immunosuppressionEpilepsy

Adult onset always need to consider cause

Further investigationsASD on echoParadoxical embolus and therefore infarct

Other learning pointsThat an extensive unilateral lesion can also cause reduced LOC