management of comatose patient

Management of comatose Management of comatose patient patient

DR.H.N.SARKERDR.H.N.SARKER

MBBS,FCPS,MRCP(UK),MBBS,FCPS,MRCP(UK),

FRCP(Edin)FRCP(Edin)

Associate ProfessorAssociate Professor

MedicineMedicine

IntroductionIntroduction

Consciousness means wakefulness Consciousness means wakefulness with awareness of self and with awareness of self and surroundings.surroundings.

The state of consciousness is the The state of consciousness is the product of complex interactions product of complex interactions between parts of the between parts of the reticular reticular activating systemactivating system in brainstem and in brainstem and medial part of thalamus , cortex, medial part of thalamus , cortex, and all sensory stimuli. and all sensory stimuli.


For a person, in order to maintain For a person, in order to maintain consciousness, the two important consciousness, the two important neurological components must function neurological components must function perfectly. perfectly.

The first is the cerebral cortex which is the The first is the cerebral cortex which is the gray matter covering the outer layer of the gray matter covering the outer layer of the brain, and the other is a structure located brain, and the other is a structure located in the brainstem, called reticular activating in the brainstem, called reticular activating system (RAS or ARAS).system (RAS or ARAS).


Injury to either, or both of these Injury to either, or both of these components is sufficient to cause a components is sufficient to cause a patient to experience altered patient to experience altered consciousness.consciousness.

IntroductionIntroduction Altered / Disturbed consciousness: Altered / Disturbed consciousness:

definitions of some terms-definitions of some terms-■ ■ Clouding of consciousness Clouding of consciousness ––

means reduced wakefulness and/or self-means reduced wakefulness and/or self-awareness, sometimes with confusion.awareness, sometimes with confusion.

■ ■ Confusion Confusion means that the subject means that the subject is bewildered and misinterprets his/her is bewildered and misinterprets his/her surroundings.surroundings.

■ ■ Delirium Delirium is a state of confusion, is a state of confusion, sometimes with visual hallucination, and sometimes with visual hallucination, and often high arousal (e.g. deliriumoften high arousal (e.g. deliriumtremens, ).tremens, ).


■ ■ Sleep Sleep is normal mental and physical is normal mental and physical inactivity: the subject can be roused.inactivity: the subject can be roused.■ ■ Stupor Stupor is abnormal; a sleepy state from is abnormal; a sleepy state from which the subject can be aroused by which the subject can be aroused by vigorous or repeated stimuli.vigorous or repeated stimuli.The term is also used for psychiatric The term is also used for psychiatric states, e.g. catatonic and depressive states, e.g. catatonic and depressive stupor.stupor.■ ■ Coma Coma means unrousable means unrousable unresponsiveness. Coma is a state of unresponsiveness. Coma is a state of unconsciousness whereby a patient cannot unconsciousness whereby a patient cannot react with the surrounding environment.react with the surrounding environment.

Mechanisms of comaMechanisms of coma

Altered consciousness is produced by Altered consciousness is produced by three mechanisms affecting three mechanisms affecting brainstem, reticular formation and brainstem, reticular formation and cortex.cortex.■ ■ Diffuse brain dysfunctionDiffuse brain dysfunction. . Generalized severe metabolic or Generalized severe metabolic or toxic disorders (e.g. alcohol, toxic disorders (e.g. alcohol, sedatives, uraemia, septicaemia) sedatives, uraemia, septicaemia) depress overall brain function.depress overall brain function.


■ ■ Direct effect within the Direct effect within the brainstembrainstem. A brainstem lesion . A brainstem lesion inhibits the reticular formation.inhibits the reticular formation.

■ ■ Pressure effect on the Pressure effect on the brainstembrainstem. A mass lesion within the . A mass lesion within the brain compresses the brainstem, brain compresses the brainstem, inhibiting the reticular formation.inhibiting the reticular formation.


A single focal hemisphere (or A single focal hemisphere (or cerebellar) lesion does not produce cerebellar) lesion does not produce coma unless it compresses or coma unless it compresses or damages the brainstem. damages the brainstem.

Causes of comaCauses of coma

Principal causes of comaPrincipal causes of coma

Diffuse brain dysfunctionDiffuse brain dysfunction Drug overdose, alcohol abuseDrug overdose, alcohol abuse CO poisoning, anaesthetic gasesCO poisoning, anaesthetic gases Hypoglycaemia, hyperglycaemiaHypoglycaemia, hyperglycaemia Hypoxic/ischaemic brain injuryHypoxic/ischaemic brain injury Hypertensive encephalopathyHypertensive encephalopathy


Diffuse brain dysfunctionDiffuse brain dysfunction Severe uraemia Severe uraemia Hepatocellular failure Hepatocellular failure Respiratory failure with CO2 retention Respiratory failure with CO2 retention Hypercalcaemia, hypocalcaemiaHypercalcaemia, hypocalcaemia Hypoadrenalism, hypopituitarism and Hypoadrenalism, hypopituitarism and

hypothyroidismhypothyroidism


Diffuse brain dysfunctionDiffuse brain dysfunction Hyponatraemia, hypernatraemiaHyponatraemia, hypernatraemia Metabolic acidosisMetabolic acidosis Hypothermia, hyperpyrexiaHypothermia, hyperpyrexia Trauma to brainTrauma to brain Epilepsy Epilepsy


Diffuse brain dysfunctionDiffuse brain dysfunction Encephalitis, cerebral malaria, Encephalitis, cerebral malaria,

septicaemiasepticaemia Subarachnoid haemorrhageSubarachnoid haemorrhage Metabolic rarities, e.g. porphyriaMetabolic rarities, e.g. porphyria Cerebral oedema from chronic Cerebral oedema from chronic

hypoxia hypoxia


Direct effect within brainstemDirect effect within brainstem• Brainstem haemorrhage or infarctionBrainstem haemorrhage or infarction• Brainstem neoplasm, e.g. gliomaBrainstem neoplasm, e.g. glioma• Brainstem demyelinationBrainstem demyelination• Wernicke–Korsakoff syndromeWernicke–Korsakoff syndrome• TraumaTrauma


Pressure effect on brainstemPressure effect on brainstem• Hemisphere tumour, infarction, Hemisphere tumour, infarction,

haematoma, abscess,haematoma, abscess,• encephalitis or traumaencephalitis or trauma• Cerebellar massCerebellar mass


Common causes of coma Common causes of coma (remember by Mnomonic-(remember by Mnomonic-AEIOU,DAMM )AEIOU,DAMM )• A-Alcohol, AbscessA-Alcohol, Abscess• E- Epilepsy, Encephalitis, Endocrine and E- Epilepsy, Encephalitis, Endocrine and

Electrolyte disturbanceElectrolyte disturbance• I- Head injury, Brainstem Infarction or I- Head injury, Brainstem Infarction or

haemorrhage haemorrhage


O-Opium,drug OverdoseO-Opium,drug Overdose U- UraemiaU- Uraemia D- Diabetes(Hypoglycaemia, diabetic D- Diabetes(Hypoglycaemia, diabetic

ketoacidosis, nonketotic ketoacidosis, nonketotic hyperosmolar hyperglycemia)hyperosmolar hyperglycemia)


A-Apoplexy, Epidural and subdural A-Apoplexy, Epidural and subdural hemorrhage, Subarachnoid hemorrhage, Subarachnoid hemorrhagehemorrhage

M- Meningitis,cerebral MalariaM- Meningitis,cerebral Malaria M-Metabolic(hepatic failure)M-Metabolic(hepatic failure)


A-Apoplexy, Epidural and subdural A-Apoplexy, Epidural and subdural hemorrhage, Subarachnoid hemorrhage, Subarachnoid hemorrhagehemorrhage

M- Meningitis, cerebral MalariaM- Meningitis, cerebral Malaria M-Metabolic (hepatic failure)M-Metabolic (hepatic failure)

Approach to the Patient: ComaApproach to the Patient: Coma

Immediate assessmentImmediate assessment

Actions that take seconds save lives.Actions that take seconds save lives.• Assess airway, breathing, circulation-Assess airway, breathing, circulation-

resuscitate.resuscitate.• Give 100% O2, monitor pulse oximetry Give 100% O2, monitor pulse oximetry

and obtain venous access.and obtain venous access.• Withdraw blood for glucose, other Withdraw blood for glucose, other

biochemical parameters and drug biochemical parameters and drug screening screening

Immediate assessmentImmediate assessment

Record the GCS and check the pupil Record the GCS and check the pupil size and reaction.size and reaction.

Check the bedside glucose and the Check the bedside glucose and the temperature.temperature.

Consider the differential diagnosis.Consider the differential diagnosis. Look for a Medic alert bracelet or Look for a Medic alert bracelet or

necklace.necklace.

Immediate therapyImmediate therapy

If hypoglycaemia, give 50 ml 50% If hypoglycaemia, give 50 ml 50% glucose i.v.glucose i.v.

If hypothermia, start rewarming.If hypothermia, start rewarming. If pupils are small, R rate is low or If pupils are small, R rate is low or

signs of drug abuse are present, give signs of drug abuse are present, give 400µg of naloxane i.v stat and 400µg of naloxane i.v stat and repeat.repeat.

Subsequent managementSubsequent management

After initial therapy, subsequent After initial therapy, subsequent assessment is done by taking history assessment is done by taking history and physical examination including and physical examination including General and neurological General and neurological examinationexamination

History History

All possible information fromAll possible information from

RelativesRelatives

ParamedicsParamedics

Ambulance crewAmbulance crew

BystandersBystanders

HistoryHistory

Particularly about the mood of onset Particularly about the mood of onset and circumstancesand circumstances

Previous medical history-Previous medical historyepilepsy, DM, drug historyepilepsy, DM, drug history

Clues obtained from pt’s clothing and Clues obtained from pt’s clothing and handbag handbag

Examination Examination

A thorough examination of all A thorough examination of all systems is essential but concentrate systems is essential but concentrate on the following.on the following.

1.Trauma requires complete 1.Trauma requires complete exposure and roll to examine backexposure and roll to examine back

2. Neddle mark 2. Neddle mark

ExaminationExamination

3. Severity of coma-assessed by 3. Severity of coma-assessed by Glasgow Coma ScaleGlasgow Coma Scale

Eye opening (E)Eye opening (E)• Spontaneous Spontaneous 44• To speech To speech 33• To pain To pain 22• No response No response 11


Motor response (M)Motor response (M)• Obeys Obeys 66• LocalizesLocalizes 55• Withdraws Withdraws 44• FlexionFlexion 3 3• ExtensionExtension 22• No responseNo response 11


Verbal response (V)Verbal response (V)• Orientated Orientated 55• Confused conversation Confused conversation 44• Inappropriate wordsInappropriate words 3 3• Incomprehensible sounds 2Incomprehensible sounds 2• No response No response 11


Glasgow Coma Scale = E + M + VGlasgow Coma Scale = E + M + V

(GCS minimum = 3: maximum = 15)(GCS minimum = 3: maximum = 15)


4. Pupil size and reaction-4. Pupil size and reaction-


5.Spontaneous eye movement-5.Spontaneous eye movement-

Abnormal conjugate deviation Abnormal conjugate deviation suggests intracerebral damage. suggests intracerebral damage.

Dysconjugate deviation implies Dysconjugate deviation implies damage to 3,4 or 6th nerve damage to 3,4 or 6th nerve

palsypalsy


6.Respiratory rate and pattern- 6.Respiratory rate and pattern-


7. 7. Signs of Lateralisation suggest focal Signs of Lateralisation suggest focal neurological damageneurological damage

InvestigationsInvestigations

Often, the cause is evident (e.g. head Often, the cause is evident (e.g. head injury, cerebral haemorrhage, self-injury, cerebral haemorrhage, self-poisoning); poisoning);

if no cause is evident, further if no cause is evident, further investigations are essential.investigations are essential.


Blood and urineBlood and urine■ ■ Drugs screen (e.g. salicylates, diazepam, Drugs screen (e.g. salicylates, diazepam, narcotics, amfetamines).narcotics, amfetamines).■ ■ Routine biochemistry (urea, electrolytes, Routine biochemistry (urea, electrolytes, glucose, calcium, liver biochemistry).glucose, calcium, liver biochemistry).■ ■ Metabolic and endocrine studies (TSH, Metabolic and endocrine studies (TSH, cortisol).cortisol).■ ■ Blood and urine cultures.Blood and urine cultures.■ ■ Other, e.g. cerebral malaria (request Other, e.g. cerebral malaria (request thick blood film).thick blood film).


ImagingImaging

CT or MR brain imaging may indicate CT or MR brain imaging may indicate an an unsuspected mass lesion or unsuspected mass lesion or intracranial intracranial haemorrhage.haemorrhage.

CSF examinationCSF examination

Lumbar puncture should be Lumbar puncture should be performed in coma only after careful risk performed in coma only after careful risk assessment. It is contraindicated when an assessment. It is contraindicated when an intracranial mass lesion is a possibility:intracranial mass lesion is a possibility:


CT is essential to exclude this. CSF CT is essential to exclude this. CSF examination is likely to alter therapy examination is likely to alter therapy only if undiagnosed only if undiagnosed meningoencephalitis or other meningoencephalitis or other infection is present.infection is present.

ElectroencephalographyElectroencephalography

EEG is of some value in the diagnosis EEG is of some value in the diagnosis of metabolic coma and encephalitis.of metabolic coma and encephalitis.

ManagementManagement

Comatose and stuporose patients – Comatose and stuporose patients – at home or outside, on a trolley, in a at home or outside, on a trolley, in a ward or ITU – need immediate careful ward or ITU – need immediate careful nursing,nursing,• meticulous attention to the airway meticulous attention to the airway

(protected airway) , and (protected airway) , and • frequent monitoring of vital functions frequent monitoring of vital functions

and high flow O2.and high flow O2.


Longer-term essentials are:Longer-term essentials are:

■ ■ skin care – turning (to avoid skin care – turning (to avoid pressure pressure sores and pressure palsies), sores and pressure palsies), removal removal of jewellery, of jewellery,

a suitable pressure-relieving a suitable pressure-relieving mattress. mattress.

■ ■ oral hygiene – mouthwashes, oral hygiene – mouthwashes, suctionsuction

■ ■ eye care – prevention of corneal eye care – prevention of corneal damage (lid taping, irrigation)damage (lid taping, irrigation)


■ ■ fluids – intragastric or i.v.fluids – intragastric or i.v.

■ ■ calories – liquid diet through a fine calories – liquid diet through a fine intragastric tube, 3000 kcal dailyintragastric tube, 3000 kcal daily

■ ■ sphincters – catheterization when sphincters – catheterization when essential ; rectal evacuation.essential ; rectal evacuation.


Broad spectrum antibiotics and/or Broad spectrum antibiotics and/or antivirals should be given empirically antivirals should be given empirically if there is any suggestion of bacterial if there is any suggestion of bacterial infection or encephalitis . infection or encephalitis .

Half-hourly neuro-observations.Half-hourly neuro-observations.


Specific treatment- Specific treatment-

Treatment of specific causes of Treatment of specific causes of coma.coma.