Approach toApproach to The Unconscious PatientThe Unconscious Patient

Dr. Sharat S. KolkeDr. Sharat S. Kolke

MD, DNBMD, DNB

Fauziya HospitalKohinoor Hospital

The Unconscious PatientThe Unconscious Patient

Wakefulness depends on the integrityWakefulness depends on the integrity

of both cerebral hemispheres and theof both cerebral hemispheres and the

ascending reticular activating formation ofascending reticular activating formation of

the brain stem.the brain stem.

The Reticular formationThe Reticular formation

The Reticular formationThe Reticular formation

Causes of ComaCauses of Coma

( A ) Localised mass lesions, ( A ) Localised mass lesions, producing pressure effectproducing pressure effect : :

i) Supratentorial causing i) Supratentorial causing herniationherniation

ii) Infratentorial causing ii) Infratentorial causing compressioncompression

( C ) Psychiatric diseases( C ) Psychiatric diseases

( B ) Diffuse neurona! lesions

i) Infection

ii) Metabolic encephalopathies

iii) Drug intoxication

iv) Haemorrhage ( subarachnoid )

v) Trauma (generalised brain oedema)

vi) Ischaemia ( anoxia )

Clinico-pathological approachClinico-pathological approach

ApproachApproach

General examinationGeneral examination

      SkinSkin

(for example, rash, anaemia, cyanosis, jaundice) (for example, rash, anaemia, cyanosis, jaundice)

TemperatureTemperature

(fever-infection /hypothermia-drugs, (fever-infection /hypothermia-drugs, hypothyroid /circulatory failure) hypothyroid /circulatory failure)

Blood pressureBlood pressure

(for example, septicaemia/Addison's disease) (for example, septicaemia/Addison's disease)

General examinationGeneral examinationBreathBreath

(eg, fetor hepaticus) (eg, fetor hepaticus)

CardiovascularCardiovascular

(eg, murmurs, arrhythmia) (eg, murmurs, arrhythmia)

Abdomen Abdomen

(eg, organomegaly)   (eg, organomegaly)   

Neurological (general)Neurological (general)      

Head, neck and eardrum (trauma)   Head, neck and eardrum (trauma)   

Meningism Meningism

(SAH/ meningitis)   (SAH/ meningitis)   

Fundoscopy Fundoscopy

ApproachApproach

DefinitionDefinition

Unconsciousness is defined as lossUnconsciousness is defined as loss

of awareness of the environment and it canof awareness of the environment and it can

be divided into three stages :be divided into three stages :

( a ) ( a ) ObtundationObtundation; responds to verbal; responds to verbal

stimuli although slow and inappropriate.stimuli although slow and inappropriate.

( b ) ( b ) StuporStupor; the subject can be roused; the subject can be roused

only by vigorous and repeated noxious stimuli.only by vigorous and repeated noxious stimuli.

( c )( c ) Coma Coma; unarousable and unresponsive.; unarousable and unresponsive.

Level of consciousnessLevel of consciousness

Glasgow coma scaleGlasgow coma scale

Eye openingEye opening

Verbal response  Verbal response  

Motor responseMotor response

Glasgow coma scaleGlasgow coma scaleEye Opening

N ever 1To pain 2To verbal stimuli 3Spontaneously 4

Best Verbal Response

No response 1Incomprehensible sounds 2Inappropriate words 3Disoriented and converses 4Oriented and converses 5

Best Motor Response

No response 1Extension (Decerbration) 2Flexion (Decortication) 3Flexion withdrawal 4Only localises pain 5No response 6

Glasgow coma scaleGlasgow coma scale

More commonly used to assess the severity More commonly used to assess the severity of Brain injuryof Brain injury

Lesser the score deeper the level on Lesser the score deeper the level on unconsciousnessunconsciousness

Coma is defined as a score of 8 or lessComa is defined as a score of 8 or less

Brain DeathBrain Death

Deep unresponsive comaDeep unresponsive coma

Absence of brain stem activityAbsence of brain stem activity

Large non reactive pupilsLarge non reactive pupils

Absent corneal responseAbsent corneal response

Absent of eye movementsAbsent of eye movements

Apnea in spite of pCo2 > Apnea in spite of pCo2 > 50mmHg50mmHg

Exclusion of drug overdose and/or Exclusion of drug overdose and/or hypothermiahypothermia

Respiratory patternRespiratory pattern

( a )( a ) HyperventilationHyperventilation - usually indicating a - usually indicating a midbrain and upper ponsmidbrain and upper pons lesion commonly lesion commonly found in metabolic diseases e.g. hepatic found in metabolic diseases e.g. hepatic coma, diabetes and generalized raised coma, diabetes and generalized raised

intracranial pressure in its early stages.intracranial pressure in its early stages.

( b )( b ) HypoventilationHypoventilation - usually indicating a - usually indicating amedullary, upper cervical spinal lesion medullary, upper cervical spinal lesion commonly found in drug overdose and commonly found in drug overdose and

later stages of cerebral herniation.later stages of cerebral herniation.

Respiratory patternRespiratory pattern

( c ) ( c ) Cheyne-Stoke respirationCheyne-Stoke respiration - usually indicating - usually indicating a diencephalic lesion commonly found in a diencephalic lesion commonly found in central transtentorial herniation and central transtentorial herniation and

obstructive,hydrocephalus.obstructive,hydrocephalus.

( d ) ( d ) Ataxic respirationAtaxic respiration (completely irregular (completely irregular breathing)breathing) - usually indicating brain-stem - usually indicating brain-stem dysfunction of a diffuse nature.dysfunction of a diffuse nature.

Pupillary size and reactionPupillary size and reaction

(a) Medium to dilated symmetrical pupils fixed to light – structural disease of the brain stem.

(b) Small symmetrical pupils reactive to light - metabolic diseases and drug overdose.

(c) Unequal pupil fixed to light - intracranial mass lesion producing 3rd nerve palsy, e.g. in unilateral uncal herniation.

Pupillary size and reactionPupillary size and reaction

Eye movementsEye movements( a ) Vestibulo-ocular reflexes –( a ) Vestibulo-ocular reflexes –

Douching of one ear with Douching of one ear with cold watercold water produces ipsilateral produces ipsilateral deviation of both eyes with a contralateral quick phase deviation of both eyes with a contralateral quick phase nystagmus lasting for 1—2 minutes.nystagmus lasting for 1—2 minutes.

Use of Use of hot waterhot water produces the opposite effect i.e. produces the opposite effect i.e. contralateral deviation with ipsilateral quick phase nystagmus. contralateral deviation with ipsilateral quick phase nystagmus.

Bilateral douching with cold water gives rise to downward Bilateral douching with cold water gives rise to downward deviation with upward nystagmus and with hot water the deviation with upward nystagmus and with hot water the opposite response.opposite response.

Absence or abnormal response indicates brain-stem Absence or abnormal response indicates brain-stem dysfunction.dysfunction.

( b ) ( b ) Oculo-cephalic reflexes or (Doll's eye Oculo-cephalic reflexes or (Doll's eye movement )movement ) – –

Normal response consist of deviation of both Normal response consist of deviation of both eyes to the opposite direction of head rotation.eyes to the opposite direction of head rotation.

Again absence or abnormal responseAgain absence or abnormal response

indicates brain-stem dysfunction.indicates brain-stem dysfunction.

Eye movementsEye movements

Eye movementsEye movements

5. Motor responses5. Motor responses

This is elicited by applying peripheral noxious stimuli e.g. This is elicited by applying peripheral noxious stimuli e.g. pinching of limbs, rubbing the sternum to elicit pain.pinching of limbs, rubbing the sternum to elicit pain.

(a) Appropriate response(a) Appropriate response – brushing away the source of – brushing away the source of stimulus.stimulus.

((b) Inappropriate responseb) Inappropriate response – decerebrate or decorticate – decerebrate or decorticate rigidity. Motor response is also of localising valuerigidity. Motor response is also of localising value

(c) Paralysed limb will show (c) Paralysed limb will show no responseno response

Decerebrate rigidity indicates brain-stem

damage and if bilateral is usually associated

with a very poor prognosis.

Complete flaccidity with no response to noxious

stimuli is often indicative of severe central

nervous system depression due to drug

overdose.

5. Motor responses5. Motor responses

InvestigationsInvestigations

Supratorial lesions -Supratorial lesions -

1.1. Computerised tomographic scan ( CT scan )Computerised tomographic scan ( CT scan )

2.2. Carotid DSACarotid DSA

3.3. EEG ( electroencephalogram )EEG ( electroencephalogram )

Infratentorial lesions –Infratentorial lesions –

1.1. CT scan/MRICT scan/MRI

2.2. Carotid or Vertebrobasilar DSACarotid or Vertebrobasilar DSA

Diffuse neuronal lesions -Diffuse neuronal lesions -

1.1. Examination of CSF ( cerebral spine fluid )Examination of CSF ( cerebral spine fluid )

2.2. Serum glucose, calcium, Na+, K , magnesiumSerum glucose, calcium, Na+, K , magnesium

3.3. Blood gases and PHBlood gases and PH

4.4. Liver and renal functionsLiver and renal functions

5.5. Drug levelsDrug levels

InvestigationsInvestigations

ManagementManagement

Management of the comatose patient Management of the comatose patient depends on the depends on the cause.cause.

However, while the patient is undergoingHowever, while the patient is undergoing

evaluation, it is essential to :evaluation, it is essential to :

1) Maintain adequate cerebral 1) Maintain adequate cerebral oxygenation, patent air-way, assisted oxygenation, patent air-way, assisted respiration if necessary.respiration if necessary.

2) 2) Prevent aspirationPrevent aspiration - Nursing the - Nursing the

patient on the side and empty thepatient on the side and empty the

stomach.stomach.

3) Establish an 3) Establish an intravenous Siteintravenous Site for for

prompt medication - e.g. !Vprompt medication - e.g. !V

glucose/insulin; antibiotics; highglucose/insulin; antibiotics; high

dose steroid; anticonvulsants.dose steroid; anticonvulsants.

ManagementManagement