Un Un (consciousness)(consciousness)

Dr Antony ThomasDr Antony ThomasConsultant NeurologistConsultant Neurologist

UHCWUHCWAlexandra Hospital Alexandra Hospital

RedditchRedditch

Neural basis of Neural basis of consciousnessconsciousness

ConsciousnessConsciousness cannot be cannot be readily defined in terms of readily defined in terms of anything elseanything else

A state of awareness of A state of awareness of selfself and and surroundingsurrounding

Mental StatusMental Status = =

Arousal + ContentArousal + Content

Anatomy of Mental Status Anatomy of Mental Status

Ascending reticular activating system Ascending reticular activating system (ARAS)(ARAS) Activating systems of upper brainstem, Activating systems of upper brainstem,

hypothalamus, thalamushypothalamus, thalamus Determines the level of Determines the level of arousalarousal

Cerebral hemispheres and interaction Cerebral hemispheres and interaction between functional areas in cerebral between functional areas in cerebral hemisphereshemispheres Determines the Determines the intellectual and emotionalintellectual and emotional

functioningfunctioning

Interaction betweenInteraction between cerebral cerebral hemispheres and activating systemshemispheres and activating systems

Sum of patient’s Sum of patient’s intellectualintellectual (cognitive) (cognitive) functions and functions and emotionsemotions (affect) (affect)

Sensations, emotions, memories, images, Sensations, emotions, memories, images, ideas (SEMII)ideas (SEMII)

Depends upon the activities of the Depends upon the activities of the cerebral cerebral cortexcortex, the , the thalamusthalamus & their interrelationship & their interrelationship

The content of consciousness

Lesions of these structures will diminish the content of consciousness (without changing the state of consciousness)

The The ascending RASascending RAS, from the lower border , from the lower border of the of the ponspons to the to the ventromedial thalamusventromedial thalamus

The cells of origin of this system occupy a The cells of origin of this system occupy a paramedian area in the brainstem paramedian area in the brainstem

The state of consciousness (arousal)

Abnormal change in level of Abnormal change in level of arousalarousal or altered or altered content content of a patient's thought processesof a patient's thought processes

Change in the level of arousal or alertnessChange in the level of arousal or alertness

inattentiveness, lethargy, stupor, and coma.inattentiveness, lethargy, stupor, and coma.

Change in contentChange in content ““Relatively Relatively simplesimple” changes: e.g. ” changes: e.g. speech, speech,

calculations, spellingcalculations, spelling More More complexcomplex changes: changes: emotions, behavior or emotions, behavior or

personalitypersonality Examples: Examples: confusionconfusion, , disorientationdisorientation, , hallucinationshallucinations, ,

poor comprehensionpoor comprehension, or , or verbal expressive difficultyverbal expressive difficulty

Altered Mental Status

Definitions of levels of arousal Definitions of levels of arousal (conciousness)(conciousness)

Alert Alert (Conscious)(Conscious) - - Appearance of wakefulness, Appearance of wakefulness, awareness of the self and environment awareness of the self and environment

Lethargy Lethargy -- mildmild reduction in alertness reduction in alertness

ObtundationObtundation -- moderatemoderate reduction in alertness. reduction in alertness. Increased Increased response timeresponse time to stimuli. to stimuli.

StuporStupor - - Deep sleep, patient can be aroused only by Deep sleep, patient can be aroused only by vigorous and repetitivevigorous and repetitive stimulation. Returns to deep stimulation. Returns to deep sleep when not continually stimulatedsleep when not continually stimulated..

Coma (Unconscious)Coma (Unconscious) - - Sleep likeSleep like appearance and appearance and behaviorally behaviorally unresponsiveunresponsive to all external stimuli to all external stimuli ((UnarousableUnarousable unresponsivenessunresponsiveness, , eyes closedeyes closed) )

Psychogenic Psychogenic unresponsivenessunresponsiveness

The patient, although apparently The patient, although apparently unconscious, usually shows unconscious, usually shows some some response to external stimuliresponse to external stimuli

An attempt to elicit the An attempt to elicit the corneal reflexcorneal reflex may cause a vigorous contraction of may cause a vigorous contraction of the orbicularis oculithe orbicularis oculi

Marked Marked resistance to passive resistance to passive movementmovement of the limbs may be of the limbs may be present, and signs of organic disease present, and signs of organic disease are absent are absent

Locked in syndromeLocked in syndrome

Patient is Patient is awake and alertawake and alert, but , but unable unable to move or speak. to move or speak.

Pontine lesionsPontine lesions affect lateral eye affect lateral eye movement and motor controlmovement and motor control

Lesions often Lesions often sparespare vertical eye vertical eye movementsmovements and and blinking.blinking.

Vegetative

Locked-in

Confusional stateConfusional state

Major defectMajor defect: lack of attention: lack of attention DisorientationDisorientation to time > place > person to time > place > person Patient thinks Patient thinks less clearlyless clearly and and more more

slowlyslowly MemoryMemory faulty (difficulty in repeating faulty (difficulty in repeating

numbers (digit span)numbers (digit span) MisinterpretationMisinterpretation of external stimuli of external stimuli Drowsiness may Drowsiness may alternatealternate with hyper - with hyper -

excitability and irritability excitability and irritability

DeliriumDelirium

Markedly abnormal mental Markedly abnormal mental statestate Severe confusional stateSevere confusional state PLUSPLUS Visual hallucinations &/or Visual hallucinations &/or

delusionsdelusions(complex systematized dream like (complex systematized dream like state) state)

Marked: Marked: disorientation,disorientation, fear, irritability, fear, irritability, misperception of sensory stimulimisperception of sensory stimuli

Pt. Pt. out of true contactout of true contact with environment with environment and other people and other people

Common causesCommon causes: : 1.1. ToxinsToxins2.2. metabolic metabolic disordersdisorders3.3. partial complex partial complex seizuresseizures4.4. head head traumatrauma5.5. acute febrile systemic illnesses acute febrile systemic illnesses

To cause comaTo cause coma, , as defined as a state as defined as a state of of unconsciousnessunconsciousness in which the in which the eyes eyes are closedare closed and and sleep–wake cycles sleep–wake cycles absentabsent

Lesion of the cerebral Lesion of the cerebral hemisphereshemispheres extensive and bilateralextensive and bilateral

Lesions of the Lesions of the brainstembrainstem: : above the above the lower 1/3 of the ponslower 1/3 of the pons and destroy and destroy both both sides of the paramediansides of the paramedian reticulum reticulum

The use of The use of terms other than terms other than coma and stuporcoma and stupor to indicate the to indicate the degree of impairment of degree of impairment of consciousness is beset with consciousness is beset with difficulties and more important difficulties and more important is the use of coma scales is the use of coma scales ((Glasgow Coma ScaleGlasgow Coma Scale))

Glasgow Coma Scale (GCS)Glasgow Coma Scale (GCS)Best eye Best eye

response (E) response (E) Best verbal Best verbal

response (V) response (V) Best motor Best motor

response (M)response (M)

4 4 Eyes opening Eyes opening

spontaneouslyspontaneously 5 5 Oriented Oriented 6 6 Obeys commandsObeys commands

3 3 Eye opening to Eye opening to

speechspeech 4 4 ConfusedConfused 5 5 Localizes to painLocalizes to pain

2 2 Eye opening in Eye opening in response to painresponse to pain

3 3 Inappropriate Inappropriate

wordswords 4 4 Withdraws from Withdraws from

painpain

1 1 No eye opening No eye opening 2 2 Incomprehensible Incomprehensible

soundssounds 3 3 Flexion in response Flexion in response

to painto pain

1 1 None None 2 2 Extension to pain Extension to pain

1 1 No motor responseNo motor response

Individual Individual elements as well as elements as well as the sumthe sum of the score are important. of the score are important.

Hence, the score is expressed in the Hence, the score is expressed in the form "form "GCS 9GCS 9 = = EE2 2 VV4 4 MM3 3 at 07:35at 07:35

Generally, comas are classified as:Generally, comas are classified as: SevereSevere, with GCS ≤ 8 , with GCS ≤ 8 ModerateModerate, GCS 9 - 12 , GCS 9 - 12 MinorMinor, GCS ≥ 13. , GCS ≥ 13.

Approaches to DD Approaches to DD

Glucose, ABG, Lytes, Mg, Glucose, ABG, Lytes, Mg, Ca, Tox, ammoniaCa, Tox, ammonia

Unresponsive

ABCs

IV D50, narcan, flumazenil

CT

Brainstem or other

Focal signs

Diffuse brain dysfunction

metabolic/ infectious

Unconscious

Focal lesions

Tumor, ICH/SAH/ infarction

Pseudo-Coma

Psychogenic, Looked-in,

NM paralysis

LP± CT

Y N

Y

N

Approaches to DD Approaches to DD

General examination:General examination:

On arrival to ER immediate attention to: On arrival to ER immediate attention to:

1.1. AirwayAirway

2.2. CirculationCirculation

3.3. establishing establishing IV accessIV access

4.4. Blood Blood should be withdrawn: estimation should be withdrawn: estimation of of glucoseglucose # # other biochemicalother biochemical parameters # parameters # drugdrug screening screening

Attention is then directed towardsAttention is then directed towards::

1.1. Assessment of the patientAssessment of the patient

2.2. SeveritySeverity of the coma of the coma

3.3. DiagnosticDiagnostic evaluation evaluation All possible information from:All possible information from:

1.1. RelativesRelatives

2.2. ParamedicsParamedics

3.3. Ambulance personnelAmbulance personnel

4.4. BystandersBystanders

particularly about the particularly about the mode of onsetmode of onset

Previous medical historyPrevious medical history: : 1.1. EpilepsyEpilepsy

2.2. DM, Drug historyDM, Drug history

CluesClues obtained from the patient's obtained from the patient's1.1. ClothingClothing or or

2.2. HandbagHandbag

Careful examination forCareful examination for 1.1. TraumaTrauma requires complete exposure and requires complete exposure and

‘log roll’ to examine the ‘log roll’ to examine the backback

2.2. Needle marks Needle marks

If head trauma is suspectedIf head trauma is suspected, the , the examination must await examination must await adequate adequate stabilization of the neck. stabilization of the neck.

Glasgow Coma ScaleGlasgow Coma Scale:: the the severity severity of comaof coma is essential for subsequent is essential for subsequent management. management.

Following thisFollowing this, particular attention , particular attention should be paid to should be paid to brainstem and brainstem and motormotor function. function.

TemperatureTemperatureHypothermiaHypothermia Hypopituitarism, HypothyroidismHypopituitarism, Hypothyroidism ChlorpromazineChlorpromazine Exposure to low temperature Exposure to low temperature

environments,environments, cold-water cold-water immersionimmersion

Risk of hypothermia in the elderly Risk of hypothermia in the elderly with inadequately heated rooms, with inadequately heated rooms, exacerbated by immobility.exacerbated by immobility.

C/P:C/P: generalized generalized rigidityrigidity and muscle and muscle fasciculationfasciculation but true shivering may but true shivering may be absent. (a low-reading be absent. (a low-reading rectal rectal thermometerthermometer is required). is required).

HypoxiaHypoxia and and hypercarbiahypercarbia are are common. common.

Treatment:Treatment:

1.1. Gradual Gradual warming warming is necessary is necessary

2.2. May require May require peritoneal dialysis with peritoneal dialysis with warmwarm fluids. fluids.

Hyperthermia (febrile Coma)Hyperthermia (febrile Coma)

InfectiveInfective: encephalitis, meningitis: encephalitis, meningitis VascularVascular: pontine, subarachnoid hge: pontine, subarachnoid hge MetabolicMetabolic: thyrotoxic, Addisonian : thyrotoxic, Addisonian

crisiscrisis ToxicToxic: belladonna, salicylate poisoning: belladonna, salicylate poisoning SunSun stroke, stroke, heatheat stroke stroke Coma with Coma with 2ry infection2ry infection: UTI, : UTI,

pneumonia, bed sores. pneumonia, bed sores.

Hyperthermia or heat strokeHyperthermia or heat stroke

Loss of thermoregulation dt. prolonged Loss of thermoregulation dt. prolonged exertion in a exertion in a hot environmenthot environment

Initial Initial ↑↑ in body in body temperaturetemperature with with profuse profuse sweatingsweating followed by followed by

hyperpyrexiahyperpyrexia, an abrupt , an abrupt cessation of cessation of sweatingsweating, , and thenand then

rapid onset of comarapid onset of coma, , convulsionsconvulsions, and , and deathdeath

This may be This may be exacerbated by certain exacerbated by certain drugsdrugs, ‘Ecstasy’ abuse—involving a loss , ‘Ecstasy’ abuse—involving a loss of the thirst reaction in individuals of the thirst reaction in individuals engaged in engaged in prolonged dancingprolonged dancing. .

Other causesOther causes TetanusTetanus Pontine hgePontine hge Lesions in the floor of the third ventricleLesions in the floor of the third ventricle Neuroleptic malignant syndromeNeuroleptic malignant syndrome Malignant hyperpyrexia with Malignant hyperpyrexia with

anaesthetics. anaesthetics.

Heat stroke neurological sequelaeHeat stroke neurological sequelae

Paraparesis.Paraparesis. Cerebellar Cerebellar ataxia.ataxia. DementiaDementia (rare) (rare)

PulsePulse BradycardiaBradycardia: brain tumors, opiates, : brain tumors, opiates,

myxedema.myxedema. TachycardiaTachycardia: hyperthyroidism, uremia: hyperthyroidism, uremia

Blood PressureBlood Pressure HighHigh: hypertensive encephalopathy: hypertensive encephalopathy LowLow: Addisonian crisis, alcohol, : Addisonian crisis, alcohol,

barbiturate barbiturate

SkinSkin Injuries, BruisesInjuries, Bruises: traumatic causes: traumatic causes Dry SkinDry Skin: DKA, Atropine: DKA, Atropine Moist skinMoist skin: Hypoglycemic coma: Hypoglycemic coma Cherry-redCherry-red: CO poisoning: CO poisoning Needle marksNeedle marks: drug addiction: drug addiction RashesRashes: meningitis, endocarditis : meningitis, endocarditis

PupilsPupils SizeSize, , inequalityinequality, reaction to a bright, reaction to a bright

lightlight. . An important general rule:An important general rule: most most

metabolicmetabolic encephalopathies give encephalopathies give small small pupils with pupils with preserved light reflex.preserved light reflex.

Atropine,Atropine, and and cerebral anoxiacerebral anoxia tend to tend to dilatedilate the pupils, and the pupils, and opiatesopiates will will constrictconstrict them. them.

Structural lesionsStructural lesions are more commonly are more commonly associated with associated with pupillary asymmetrypupillary asymmetry and with and with loss of light reflexloss of light reflex..

Midbrain tectal lesionsMidbrain tectal lesions : round, : round, regular, medium-sized pupils, regular, medium-sized pupils, do not do not reactreact to light to light

Midbrain nuclear lesionsMidbrain nuclear lesions: medium-: medium-sized pupils, sized pupils, fixedfixed to all stimuli to all stimuli, often , often irregular and unequalirregular and unequal..

Cranial n III distal to the nucleusCranial n III distal to the nucleus: : Ipsilateral Ipsilateral fixedfixed, , dilateddilated pupil. pupil.

Pons (Tegmental lesions)Pons (Tegmental lesions) : bilaterally : bilaterally small pupilssmall pupils, {in pontine hge, may be , {in pontine hge, may be pinpointpinpoint, although , although reactivereactive}} assess the assess the light response using a light response using a magnifying glassmagnifying glass

Lateral medullary lesionLateral medullary lesion: : ipsilateral ipsilateral Horner'sHorner's syndrome. syndrome.

Occluded carotid arteryOccluded carotid artery causing causing cerebral infarction: Pupil on that side is cerebral infarction: Pupil on that side is often often small small

Small, reactive

Diencephalons

Dilated, Fixed

small, pinpointIn hge reactive

Pons

Midbrain

Ipsilateral dilated, Fixed

Medium-sized, fixed

.

The oculocephalic (doll's head) The oculocephalic (doll's head) responseresponse

Caloric oculovestibular responsesCaloric oculovestibular responses

Odour of breathOdour of breath

AcetoneAcetone: DKA: DKA Fetor HepaticusFetor Hepaticus: in hepatic coma: in hepatic coma Urineferous odourUrineferous odour: in uremic coma: in uremic coma Alcohol odourAlcohol odour: in alcohol intoxication: in alcohol intoxication

RespirationRespiration Cheyne–Stokes respirationCheyne–Stokes respiration: :

( (hyperpnoeahyperpnoea alternates with alternates with apneasapneas) is commonly found in ) is commonly found in comatose patients, often with comatose patients, often with cerebralcerebral disease, but is relatively disease, but is relatively non-specificnon-specific. .

Rapid, regular respirationRapid, regular respiration is also is also common in comatose patients and is common in comatose patients and is often found with often found with pneumoniapneumonia or or acidosisacidosis. .

Central neurogenic hyperventilationCentral neurogenic hyperventilation

Brainstem tegmentumBrainstem tegmentum ( (mostly mostly tumorstumors)): :

↑ ↑ PO2PO2, , ↓↓ PCO2PCO2, and , and

Respiratory Respiratory alkalosisalkalosis in the in the absence of any absence of any evidence of pulmonary evidence of pulmonary disease disease

Sometimes complicates Sometimes complicates hepatic encephalopathyhepatic encephalopathy

Apneustic breathingApneustic breathing BrainstemBrainstem lesions lesions PonsPons may also may also

give with a give with a pause at full pause at full inspirationinspiration

Ataxic:Ataxic: Medullary lesions:Medullary lesions: irregular irregular

respirationrespiration with with random deeprandom deep and and shallowshallow breaths breaths

Cheyne-Stocks

Ataxic

Apneustic

Central Neurogenic Hyperventilation

Cluster

Abnormal breathing patterns in Abnormal breathing patterns in comacoma

Midbrain

Pons

Medulla

ARAS

Cheynes - Stokes

Ataxic

Apneustic

Central Neurogenic

Motor functionMotor function Particular attention should be directed Particular attention should be directed

towards asymmetry of towards asymmetry of tone or movementtone or movement. . The The plantarplantar responses are usually responses are usually

extensor, but asymmetry is again extensor, but asymmetry is again important. important.

The The tendon reflexestendon reflexes are less useful. are less useful. The motor The motor response to painful stimuliresponse to painful stimuli

should be assessed carefully (part of GCS) should be assessed carefully (part of GCS)

Painful stimuliPainful stimuli: supraorbital nerve : supraorbital nerve pressure and nail-bed pressure. pressure and nail-bed pressure. Rubbing Rubbing of the of the sternumsternum should be should be avoidedavoided (bruising and distress to the relatives)(bruising and distress to the relatives)

Patients may localize or exhibit a variety Patients may localize or exhibit a variety of responses, of responses, asymmetryasymmetry is important is important

FlexionFlexion of the of the upperupper limb with limb with extensionextension of the of the lower lower limb limb ((decorticate decorticate responseresponse) and ) and extension of the extension of the upper and lower upper and lower limb limb (decerebrate (decerebrate response) response) indicate indicate a more severe a more severe disturbance and disturbance and prognosis. prognosis.

Signs of lateralizationSigns of lateralization

Unequal Unequal pupilspupils Deviation of the Deviation of the eyeseyes to one side to one side FacialFacial asymmetry asymmetry Turning of the Turning of the headhead to one side to one side Unilateral hypo-hyperUnilateral hypo-hypertoniatonia Asymmetric deep Asymmetric deep reflexesreflexes Unilateral extensor Unilateral extensor plantarplantar response response

(Babinski)(Babinski) Unilateral focal or Jacksonian Unilateral focal or Jacksonian fitsfits

Head and neckHead and neck The headThe head

1.1. Evidence of injury Evidence of injury

2.2. Skull should be palpated for Skull should be palpated for depressed fractures. depressed fractures.

The ears and nose:The ears and nose: haemorrhage haemorrhage and leakage of CSFand leakage of CSF

The fundi:The fundi: papilloedema or papilloedema or subhyaloid or retinal haemorrhages subhyaloid or retinal haemorrhages

NeckNeck: In the presence of trauma to : In the presence of trauma to the head, associated trauma to the the head, associated trauma to the neck should be assumed until neck should be assumed until proven otherwise.proven otherwise.

Positive Positive Kernig's signKernig's sign : a meningitis : a meningitis or SAH. or SAH. If established as safe to do If established as safe to do so, the cervical spine should be so, the cervical spine should be gently flexed gently flexed

Neck stiffnessNeck stiffness may occur: may occur:

1.1. ↑ ↑ ICPICP

2.2. incipient tonsillar herniation incipient tonsillar herniation

Causes of Causes of COMACOMA

Cerebrovascular disease is a frequent Cerebrovascular disease is a frequent cause of coma. cause of coma.

Mechanism:Mechanism:

Impairment of perfusion of the RAS Impairment of perfusion of the RAS With With hypotensionhypotension Brainstem herniationBrainstem herniation ( parenchymal ( parenchymal

hge, swelling from infarct, or more hge, swelling from infarct, or more rarely, extensive brainstem infarction)rarely, extensive brainstem infarction)

CNS causes of coma

Loss of consciousness is commonLoss of consciousness is common with SAH with SAH

only about 1/2 of patients only about 1/2 of patients recover from the initial effects of recover from the initial effects of the haemorrhage. the haemorrhage.

Causes of comaCauses of coma: :

1.1. Acute ↑Acute ↑ICPICP and and

2.2. Later, Later, vasospasmsvasospasms, , hyponatraemiahyponatraemia

Subarachnoid haemorrhage

May cause a rapid decline in May cause a rapid decline in consciousness, from consciousness, from

1.1. Rupture into the ventriclesRupture into the ventricles

2.2. or subsequent or subsequent herniationherniation and and brainstem compression. brainstem compression.

Cerebellar haemorrhage or infarctCerebellar haemorrhage or infarct with with

1.1. Subsequent Subsequent oedemaoedema

2.2. Direct brainstem compressionDirect brainstem compression, early , early decompression can be lifesaving. decompression can be lifesaving.

Parenchymal haemorrhage

The critical blood flow in humans The critical blood flow in humans required to maintain effective required to maintain effective cerebral activity is about cerebral activity is about 20 20 ml/100 g/minml/100 g/min and and any fall below any fall below this leads rapidly to cerebral this leads rapidly to cerebral insufficiency. insufficiency.

The causes: The causes:

1.1. syncopesyncope in in youngeryounger patients patients

2.2. cardiaccardiac disease in disease in older older patients. patients.

Hypotension

Now Now rare with better control of rare with better control of blood pressure. blood pressure.

C/PC/P: impaired consciousness, : impaired consciousness, grossly raised blood pressure, grossly raised blood pressure, papilloedema. papilloedema.

Neuropathologically: Neuropathologically: fibrinoid fibrinoid necrosis, arteriolar thrombosis, necrosis, arteriolar thrombosis, microinfarction, and cerebral microinfarction, and cerebral oedemaoedema (failure of autoregulation) (failure of autoregulation)

Hypertensive encephalopathy

Mass effectsMass effects: tumours, abscesses, : tumours, abscesses, haemorrhage, subdural, haemorrhage, subdural, extradural haematoma, brainstem extradural haematoma, brainstem herniation→ distortion of the RAS.herniation→ distortion of the RAS.

C/PC/P: depends on normal variation : depends on normal variation in the tentorial aperture, site of in the tentorial aperture, site of lesion, and the speed of lesion, and the speed of development. development.

Raised intracranial pressure

Herniation and loss of consciousness Herniation and loss of consciousness Lesions located deeply, laterally, or in Lesions located deeply, laterally, or in the temporal lobes > located at a the temporal lobes > located at a distance, such as the frontal and distance, such as the frontal and occipital lobes. occipital lobes.

Rate of growth: Rate of growth: slowly growing slowly growing tumours may achieve a substantial tumours may achieve a substantial size and distortion of cerebral size and distortion of cerebral structure without impairment of structure without impairment of consciousness, in contrast to small consciousness, in contrast to small rapidly expanding lesions rapidly expanding lesions

Central herniationCentral herniation involves involves downward displacement of the downward displacement of the upper brainstemupper brainstem

Uncal herniationUncal herniation in which the in which the medial temporal lobe herniates medial temporal lobe herniates through the tentorium through the tentorium

The leading cause of The leading cause of deathdeath below the below the age of 45, head injury accounts for age of 45, head injury accounts for 1/2 of all trauma deaths 1/2 of all trauma deaths

A major causeA major cause of patients presenting of patients presenting with with comacoma. .

A A historyhistory is usually available and, if is usually available and, if not, not, signs of injurysigns of injury such as bruising of such as bruising of the scalp or skull fracture lead one to the scalp or skull fracture lead one to the diagnosis the diagnosis

Head injury

Other Neurological causesOther Neurological causes

InfectionsInfections Epileptic SeizuresEpileptic Seizures Raised ICP ( Posterior Fossa tumours, Raised ICP ( Posterior Fossa tumours,

hydrocephalus)hydrocephalus) Sleep disordersSleep disorders StrokeStroke Basilar Artery MigraineBasilar Artery Migraine

OthersOthers

Cardiac arrhythmiaCardiac arrhythmia HOCMHOCM PEPE ASAS

Metabolic causes of comaMetabolic causes of coma

Hepatic ComaHepatic Coma

Renal ComaRenal Coma

DKADKA

HONKHONK

Hypglycaemic ComaHypglycaemic Coma

Pituitary FailurePituitary Failure Pituitary ApoplexyPituitary Apoplexy Myxedema ComaMyxedema Coma HyperthyroidismHyperthyroidism Adrenocortical FailureAdrenocortical Failure

Other endocrine causes of coma

Hypo & Hyper CaHypo & Hyper Ca

Hypo & Hyper MgHypo & Hyper Mg

Ca, Mg metabolism

SeizuresSeizures

Definition:- Definition:- A seizure is the clinical event that result from A seizure is the clinical event that result from

abnormal excessive neuronal activity. abnormal excessive neuronal activity. Etiology:- Etiology:- --Alteration of consciousness, motor activity, behavior, Alteration of consciousness, motor activity, behavior,

sensation or autonomic function.sensation or autonomic function.-It may be viewed as a symptom of an underlying disease -It may be viewed as a symptom of an underlying disease

process.process.

Classification:-Classification:- Acute non recurrent convulsionsAcute non recurrent convulsions:-:-One or more convulsive fits that occur during the same One or more convulsive fits that occur during the same

acute illness & do not recur after recovery:-acute illness & do not recur after recovery:- Febrile convulsions. – hypertensive Febrile convulsions. – hypertensive

encephalopathy.encephalopathy. CNs infections:- meningitis, encephalitis.CNs infections:- meningitis, encephalitis. Intra cranial Hemorrhage: spontaneous, or Intra cranial Hemorrhage: spontaneous, or

traumatic traumatic Toxic:- e.g tetanus. – Intracranial tumors.Toxic:- e.g tetanus. – Intracranial tumors. Anoxic:- sudden severe asphyxia.Anoxic:- sudden severe asphyxia. Metabolic:- hypoglycemia, hypocalcaemia, hypo Metabolic:- hypoglycemia, hypocalcaemia, hypo

or hypernateremia.or hypernateremia.

Chronic recurrent convulsions:-Chronic recurrent convulsions:-Recurrent attacks of convulsions with symptoms free Recurrent attacks of convulsions with symptoms free

intervals:-intervals:-

*Epilepsy:*Epilepsy:

-- Idiopathic. -- Idiopathic.

--Neurocutaneous synd. Such as Sturge---Neurocutaneous synd. Such as Sturge-weber, neurofibromatosis, tuberous weber, neurofibromatosis, tuberous scelosis.scelosis.

Organic secondary to brain insult:- post- Organic secondary to brain insult:- post- infection, post- traumatic, post- hypoxic, infection, post- traumatic, post- hypoxic, post- toxic.post- toxic.

Benign neonatal convulsions. Benign neonatal convulsions.

*Degenerative*Degenerative brain disease. brain disease.

*Congenital cerebral malformation.*Congenital cerebral malformation.

Electrical rhythm in epilepsyElectrical rhythm in epilepsy

EpilepsyEpilepsyDefined as Increased Neuronal ExcitabilityDefined as Increased Neuronal Excitability   

PartialPartial:- Epileptic focus start localized :- Epileptic focus start localized and remain localized: and remain localized:

Classified according to level of consciousness:Classified according to level of consciousness: No loss of consciousness:No loss of consciousness: Motor – Sensory – Autonomic.Motor – Sensory – Autonomic. Loss of Consciousness: Temporal lobe epilepsy.Loss of Consciousness: Temporal lobe epilepsy.

GeneralizedGeneralized:- :- Epileptic focus start Epileptic focus start localized then become generalizedlocalized then become generalized..

Grandmal – Febrile - Status epilepticus – Myoclonic Grandmal – Febrile - Status epilepticus – Myoclonic Clonic – Atonic.-- Petite mal (typical and atypical) – Clonic – Atonic.-- Petite mal (typical and atypical) –

Tonic.Tonic.

Unclassified Unclassified

Generalized tonic clonicGeneralized tonic clonic

(grand-mal epilepsy)(grand-mal epilepsy)The commonest form of childhood convulsions 60%:-The commonest form of childhood convulsions 60%:-

-An aura:--An aura:- unusual behaviors recognized by the mother. unusual behaviors recognized by the mother.

-Tonic phase:--Tonic phase:- powerful sustained contraction(5 powerful sustained contraction(5 minutes):-minutes):-

The patient falls to the ground stiff due to The patient falls to the ground stiff due to powerful sustained contraction of all muscles.powerful sustained contraction of all muscles.

Arm flexed - Legs extended.Arm flexed - Legs extended.

-Clonic phase:--Clonic phase:- Rhythmical contraction and relaxation Rhythmical contraction and relaxation of muscles of limbs and face:- Biting the tongue and of muscles of limbs and face:- Biting the tongue and incontinence may occur during the clonic phase.incontinence may occur during the clonic phase.

-Duration of attack is variable but if exceed 20 minutes it -Duration of attack is variable but if exceed 20 minutes it considered status epilepticus.considered status epilepticus.

-Post epileptic phase-Post epileptic phase:- The child falls in :- The child falls in deep sleep and afterwards he may be deep sleep and afterwards he may be confused or irritable.confused or irritable.

Grand-mal epilepsy has good prognosis if the Grand-mal epilepsy has good prognosis if the first attack start after the age of 3years first attack start after the age of 3years and the mental development is normal.and the mental development is normal.

Febrile convulsionFebrile convulsionDefinition:- Definition:- Generalized tonic clonic Generalized tonic clonic

convulsions which occasionally occur at the convulsions which occasionally occur at the onset of acute extra-cranial infections.onset of acute extra-cranial infections.

Incidence:-Incidence:- 3-5% in all children.3-5% in all children.

Etiology:-Etiology:- At the onset of acute extra-cranial infections At the onset of acute extra-cranial infections

such as tonsillitis.such as tonsillitis.- Febrile seizures may signify a serious - Febrile seizures may signify a serious

underlying acute infections.underlying acute infections.- In association with high environmental temp.- In association with high environmental temp.Clinical picture:-Clinical picture:- Criteria for diagnosis of simple febrile convulsions:- Criteria for diagnosis of simple febrile convulsions:-

Patient type:- Patient type:- Age: 6month to Age: 6month to 6years. - Sex: male more than 6years. - Sex: male more than female. female.

Family history: Family history: Strong positive. Strong positive. - Neurologically & metabolically - Neurologically & metabolically

free.free.

Seizures stages:-Seizures stages:- PrePre- Ictal:- Convulsions occur at the - Ictal:- Convulsions occur at the

onset of temperature 39onset of temperature 39oo c or more. c or more. IctalIctal:- Generalized tonic clonic.:- Generalized tonic clonic. Short duration:- 5-15 minutes.Short duration:- 5-15 minutes. Course:- Usually one convulsive fit Course:- Usually one convulsive fit

during the same illness.during the same illness. Post-Post-ictal:- Short postictal stupor.ictal:- Short postictal stupor.

InvestigationInvestigation Laboratory:-Laboratory:-CSF analysisCSF analysis: Indicated if any doubt exist : Indicated if any doubt exist

regarding the possibility of meningitis.regarding the possibility of meningitis.EEG:- EEG:- Indicated in Indicated in atypicalatypical febrile seizure febrile seizure persists persists

for more than 15 minutes or recurrent more for more than 15 minutes or recurrent more than than 3 time/day3 time/day, or focal seizures., or focal seizures.

A child at risk for developing A child at risk for developing epilepsy:-epilepsy:-

Positive family history of epilepsy Positive family history of epilepsy Initial febrile seizures before the age of 6 Initial febrile seizures before the age of 6

months. months. A febrile seizure.A febrile seizure. Delayed developmental milestone.Delayed developmental milestone. Associated Respiratory manifestation Associated Respiratory manifestation

(cyanosis).(cyanosis).

Prognosis:-Prognosis:- Risk for developing epilepsy Risk for developing epilepsy is 1% in children without risk factors,9% is 1% in children without risk factors,9% with risk factors.with risk factors.

Treatment:-Treatment:- Immediate first aid measures.Immediate first aid measures. Measures to lower the temperature:- Measures to lower the temperature:-

Cold fomentation / Antipyretics. Cold fomentation / Antipyretics. Treatment of the cause of fever e.g Treatment of the cause of fever e.g

Antibiotics for acute tonsillitis.Antibiotics for acute tonsillitis. Short acting anticonvulsant:- Short acting anticonvulsant:-

Diazepam (valium) 0.25mg/kg/dose.Diazepam (valium) 0.25mg/kg/dose.

Generalized absence = petit-mal Generalized absence = petit-mal epilepsyepilepsy

- The commonest age 5-9 years.- The commonest age 5-9 years.- Rare below 2years and never continue after - Rare below 2years and never continue after

15 years.15 years.- Short sudden loss of consciousness.- Short sudden loss of consciousness.- The child suddenly stops talking and stares - The child suddenly stops talking and stares

for few seconds.for few seconds.- Recovery is immediate and child resumes - Recovery is immediate and child resumes

talking.talking.- Not associated with limb movement.- Not associated with limb movement.- Recurrent up to more than 100 times/day.- Recurrent up to more than 100 times/day.- May affect school performance. May affect school performance.

Myoclonic epilepsyMyoclonic epilepsy- Occurs at any age but is more seen in infants and - Occurs at any age but is more seen in infants and

young children.young children.

- Usually associated with mental retardation.- Usually associated with mental retardation.

-The attack which is very frequent, present with -The attack which is very frequent, present with sudden symmetrical mass jerking involving all sudden symmetrical mass jerking involving all limbs.limbs.

Juvenile myoclonic epilepsyJuvenile myoclonic epilepsy-Occurs during adolescence -Occurs during adolescence

––A.D. -Chromosome No. 6A.D. -Chromosome No. 6

––The hallmark is morning myoclonus within 90 The hallmark is morning myoclonus within 90 minutes after awakening.minutes after awakening.

-Resolved with Valporic acid therapy for life.-Resolved with Valporic acid therapy for life.

Atonic (a kinetic) epilepsyAtonic (a kinetic) epilepsy- It is a type of myoclonic epilepsy.- It is a type of myoclonic epilepsy.

- Transient loss of consciousness and falling on the - Transient loss of consciousness and falling on the ground.ground.

- Then immediately the child gets up and resumes - Then immediately the child gets up and resumes activity.activity.

- The condition may be confused with petit mal.The condition may be confused with petit mal.

Benign neonatal convulsionsBenign neonatal convulsions-A.D. - Chromosome No. 20-A.D. - Chromosome No. 20

-Generalized clonic seizures -Generalized clonic seizures

-Occurs toward the end of the 1-Occurs toward the end of the 1stst week of life. week of life.

-Called familial 5-Called familial 5thth day fits. day fits.

-Favorable prognosis.-Favorable prognosis.

Infantile spasm ( West syndrome)Infantile spasm ( West syndrome)

Brief convulsionBrief convulsion of the neck, trunk and arm muscles followed of the neck, trunk and arm muscles followed byby sustained muscle contraction lasting 2 to 10 seconds.sustained muscle contraction lasting 2 to 10 seconds.

Occurs when the child awakening or going to sleep.Occurs when the child awakening or going to sleep. Each jerk is followed by a brief period of relaxation, many Each jerk is followed by a brief period of relaxation, many

clusters occurs each day.clusters occurs each day.

EEG EEG showed Hypsarrhythmia ( high- voltage slow waves, showed Hypsarrhythmia ( high- voltage slow waves, spikes and polyspikes).spikes and polyspikes).

Peak age 3-8 months. - It could be mistaken for infantile colic.Peak age 3-8 months. - It could be mistaken for infantile colic.

TreatmentTreatment by ACTH,or oral steroids, or benzodiazepines,or by ACTH,or oral steroids, or benzodiazepines,or valproic acid and vigabatrinis also promising.valproic acid and vigabatrinis also promising.

Status epilepticusStatus epilepticusDefinition:- Definition:- Continuous convulsion or repeated Continuous convulsion or repeated

convulsions without return of the level of convulsions without return of the level of consciousness more than 20 min.consciousness more than 20 min.

Causes:- Causes:- -Sudden withdrawal of anticonvulsant. -Sudden withdrawal of anticonvulsant. --Febrile Febrile convulsion in poorly controlled convulsion in poorly controlled

epileptic patient. epileptic patient. --Metabolic or toxic.Metabolic or toxic.

Management:Management:1-Stop the convulsion by:-1-Stop the convulsion by:-

- Diazepam 0.2 – 0.4mg / kg / dose I.V. or 0.5mg/kg/dose - Diazepam 0.2 – 0.4mg / kg / dose I.V. or 0.5mg/kg/dose rectally.rectally.

- Chloral hydrate or paraldehyde:- 0.15 mg/kg diluted in - Chloral hydrate or paraldehyde:- 0.15 mg/kg diluted in saline I.V or 0.5ml/kg/dose rectallysaline I.V or 0.5ml/kg/dose rectally

- If failed give general anesthesia (short acting - If failed give general anesthesia (short acting barbiturates).barbiturates).

2-Long-term anticonvulsant:- 2-Long-term anticonvulsant:- Phenobarbitone 3-5mg/kg/day.Phenobarbitone 3-5mg/kg/day. Diphenylhydantoin 5-8mg/kg/day.Diphenylhydantoin 5-8mg/kg/day.

3-Evaluation of the patient: 3-Evaluation of the patient: After the attack After the attack Todd's paralysis may occur and then resolve Todd's paralysis may occur and then resolve completely.completely.

Partial (focal) seizuresPartial (focal) seizures Motor : Motor : Jacksonian epilepsyJacksonian epilepsy (simple partial motor seizures):-(simple partial motor seizures):-

Involve the motor area of the brain and the Involve the motor area of the brain and the patient is alert.patient is alert.

Consists of clonic movements in a localized Consists of clonic movements in a localized group of muscles. Commonly at the Corner group of muscles. Commonly at the Corner of mouth, Thumb, and Great toe. of mouth, Thumb, and Great toe.

Jacksonian march:- The neuronal discharge Jacksonian march:- The neuronal discharge may spread to other parts on the same may spread to other parts on the same side or become generalized.side or become generalized.

Rarely may continue for hours or day Rarely may continue for hours or day (epilepsia partialis continue).(epilepsia partialis continue).

After the attack, there may be weakness of After the attack, there may be weakness of the part involved (Todd's) paralysis.the part involved (Todd's) paralysis.

Sensory Sensory seizures:-seizures:- (simple partial (simple partial sensory seizures):-sensory seizures):-

Localized or spreading parasethesia:- Localized or spreading parasethesia:- tingling, coldness, numbness electricity or tingling, coldness, numbness electricity or even pain.even pain.

Autonomic Autonomic seizures-seizures- (simple partial (simple partial autonomic seizures):-autonomic seizures):-

Autonomic manifestationAutonomic manifestation::

-Sweating. - Tachycardia.-Sweating. - Tachycardia. Diarrhea or Constipation. Diarrhea or Constipation. Hypertension.Hypertension. Abdominal pain (abdominal epilepsy). Abdominal pain (abdominal epilepsy). Pupillary dilatation or constriction.Pupillary dilatation or constriction.

Temporal lobe (psychomotor)Temporal lobe (psychomotor)Partial complex epilepsyPartial complex epilepsySequence of events:-Sequence of events:-

Aura:- blinking of eyes, abnormal sound, Aura:- blinking of eyes, abnormal sound, taste, smell or movement.taste, smell or movement.

Absence:- loss of consciousness.Absence:- loss of consciousness. Automatism:- automatic movements e.g: Automatism:- automatic movements e.g:

chewing, smacking of lips.chewing, smacking of lips. Amnesia:- recent amnesia for all events Amnesia:- recent amnesia for all events

during the attack.during the attack.

Treatment of epilepsyTreatment of epilepsyDuration of therapy:- Duration of therapy:-

3 or 4 years after the last convulsions in 3 or 4 years after the last convulsions in grand-mal or petit mal epilepsy in an grand-mal or petit mal epilepsy in an otherwise normal child.otherwise normal child.

Longer period or even life long for those with Longer period or even life long for those with associated neurological problems.associated neurological problems.

Advice to parents & child:-Advice to parents & child:- Give full information about the drug Give full information about the drug

therapy and stress on therapy and stress on not to stop not to stop the drugthe drug without medical advice. without medical advice.

Allow normal activities:- the child Allow normal activities:- the child should be attended by a responsible should be attended by a responsible adult while bathing or swimming.adult while bathing or swimming.

Give clear instructions about the first-Give clear instructions about the first-aid measures in case the seizures: aid measures in case the seizures:

1.1. Ensure patent airway. Ensure patent airway.

2.2. Avoid biting the tongue Avoid biting the tongue

3.3. Putting the child in the prone or side Putting the child in the prone or side position with head down.position with head down.

Anticonvulsants:Anticonvulsants:

Type of Type of seizuresseizures

Drug of Drug of choicechoice

Daily doseDaily doseSide effectsSide effects

NeonatalNeonatalPhenobarbitoPhenobarbitonene

3-5 mg/kg3-5 mg/kgIrritability,overactiIrritability,overactivityvity

Grand-malGrand-malNa-Valproat, Na-Valproat, Phentoin, Phentoin,

CarpamazepiCarpamazepinene

10-20mg/kg 10-20mg/kg 4- 4-8mg/kg 8mg/kg

10-20mg/kg10-20mg/kg

-Hepatic -Hepatic dysfunction dysfunction -Ataxia,gum -Ataxia,gum hypertrophy. hypertrophy. -Rash, Leucopenia, -Rash, Leucopenia, hepatic hepatic dysfunctiondysfunction

Focal motorFocal motorCarpamazepiCarpamazepinene

4-8mg/kg4-8mg/kgRash, Leucopenia, Rash, Leucopenia, hepatic hepatic dysfunctiondysfunction

PsychomotorPsychomotorCarpamazepiCarpamazepinene

4-8mg/kg4-8mg/kgRash, Leucopenia, Rash, Leucopenia, hepatic hepatic dysfunctiondysfunction

Myoclonic, Myoclonic, Akinetic Akinetic

ClonazepamClonazepam0.05-0.05-0.2mg/kg0.2mg/kg

Drowsiness, Drowsiness, salivation, salivation, sedationsedation

Petit-malPetit-malEthosuximideEthosuximide20-40mg/kg20-40mg/kgRash, Leucopenia, Rash, Leucopenia, hepatic hepatic dysfunctiondysfunction

Status Status EpilepticusEpilepticus

DiazepamDiazepam0.2-0.4mg/0.2-0.4mg/kgkg

Respiratory Respiratory depressiondepression

New drugs used for treatment of New drugs used for treatment of epilepsy:epilepsy:

-For-For generalized generalized seizures: seizures:• LamotrigineLamotrigine• TopiramateTopiramate• ZonisamideZonisamide-For -For partialpartial seizures: seizures:*Gabapentine*Gabapentine--ForFor Infatile spasm:Infatile spasm:*Topiramate*Topiramate*Vigabatrin*Vigabatrin

PoisoningPoisoning, , drug abusedrug abuse, and , and alcohol intoxicationalcohol intoxication

The most commonly drugs in The most commonly drugs in suicide attempts aresuicide attempts are : :

1.1. BenzodiazepinesBenzodiazepines2.2. ParacetamolParacetamol3.3. antidepressantsantidepressants. . Narcotic overdosesNarcotic overdoses (heroin)(heroin) 1.1. Pinpoint pupilsPinpoint pupils2.2. Shallow respirationsShallow respirations , , needle marksneedle marks. . 3.3. The coma is easily reversible with The coma is easily reversible with

naloxonenaloxone

Alcohol intoxicationAlcohol intoxication Apparent from the Apparent from the historyhistory, , flushed flushed

faceface, , rapid pulserapid pulse, and , and low blood low blood pressurepressure. The . The smell of alcoholsmell of alcohol on the on the breath.breath.

Intoxicated are at increased risk of Intoxicated are at increased risk of hypothermia and of head injuryhypothermia and of head injury can be can be the cause of coma. the cause of coma.

At low plasma concentrationsAt low plasma concentrations of of alcoholalcohol, , mental changesmental changes, , at higher at higher levelslevels, , comacoma ensues, >350 mg/dl may ensues, >350 mg/dl may prove prove fatalfatal..