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I prepared this presentation for CME at 108 Emergency Services GVK-EMRI, Bangalore in January 2013. I kept it simple and concise as the CME was attended by EMTs too. Hope its of help to any medical professional out there.
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Head Injury- Clinical Manifestations, Diagnosis and
Management
Head Injury- Clinical Manifestations, Diagnosis and
Management
-Dr. Vibha A PEmergency Response Care Physician
GVK-EMRI, Bangalore
Head InjuryHead Injury
• Any degree of traumatic brain injury ranging from scalp laceration to LOC to focal neurological deficits
• Any degree of traumatic brain injury ranging from scalp laceration to LOC to focal neurological deficits
Head InjuryHead Injury
• Causes
– Motor vehicle accidents
– Falls
– Assaults
– Sports-related injuries
– Firearm-related injuries
• Causes
– Motor vehicle accidents
– Falls
– Assaults
– Sports-related injuries
– Firearm-related injuries
Head InjuryHead Injury
• High potential for poor outcome
• Deaths occur at three points in time after injury:
– Immediately after the injury
– Within 2 hours after injury
– 3 weeks after injury
• High potential for poor outcome
• Deaths occur at three points in time after injury:
– Immediately after the injury
– Within 2 hours after injury
– 3 weeks after injury
Head Injury Head Injury
TYPES:• Scalp laceration• Skull Fractures• Minor Head Trauma
Concussion and post-concussion syndrome
• Major Head Trauma: Cerebral contusion
Laceration
TYPES:• Scalp laceration• Skull Fractures• Minor Head Trauma
Concussion and post-concussion syndrome
• Major Head Trauma: Cerebral contusion
Laceration
Head InjuryHead Injury
• Scalp lacerations
– The most minor type of head trauma
– Scalp is highly vascular profuse bleeding
– Major complication is infection
• Scalp lacerations
– The most minor type of head trauma
– Scalp is highly vascular profuse bleeding
– Major complication is infection
Head InjuryHead Injury
• Skull fractures
– Linear Skull Fracture
– Depressed Skull Fracture
– Diastatic Skull Fracture
– Basal Skull Fracture
– Compound Skull Fracture
– Compound elevated Skull Fracture
– Growing Skull Fracture
– Coup & Contrecoup
• Skull fractures
– Linear Skull Fracture
– Depressed Skull Fracture
– Diastatic Skull Fracture
– Basal Skull Fracture
– Compound Skull Fracture
– Compound elevated Skull Fracture
– Growing Skull Fracture
– Coup & Contrecoup
Head InjuryHead Injury
• Skull fractures
– Location of fracture alters the presentation of the manifestations
– Facial paralysis
– Conjugate deviation of gaze
– Battle’s sign, Raccoon eyes
• Skull fractures
– Location of fracture alters the presentation of the manifestations
– Facial paralysis
– Conjugate deviation of gaze
– Battle’s sign, Raccoon eyes
Battle’s SignBattle’s Sign
Fig. 55-13
Head InjuryHead Injury
• Basal Skull fractures– CSF leak (extravasation)
into ear (Otorrhea) or nose (Rhinorrhea)
– High risk infection or meningitis
– “HALO Sign ” on clothes of linen
– Possible injury to Internal carotid artery
– Permanent CSF leaks possible
• Basal Skull fractures– CSF leak (extravasation)
into ear (Otorrhea) or nose (Rhinorrhea)
– High risk infection or meningitis
– “HALO Sign ” on clothes of linen
– Possible injury to Internal carotid artery
– Permanent CSF leaks possible
Investigations Investigations
X-ray CT scan: standard modality
MRI
Bleeding from the ear or nose in cases of suspected CSF leak -"halo" or "ring" sign , when dabbed on a tissue paper
CSF leak - analyzing the glucose level and by measuring tau-transferrin.
X-ray CT scan: standard modality
MRI
Bleeding from the ear or nose in cases of suspected CSF leak -"halo" or "ring" sign , when dabbed on a tissue paper
CSF leak - analyzing the glucose level and by measuring tau-transferrin.
ManagementManagement
Pre-hospital care:• Patients with severe head injuries should be assumed to have
a cervical spine (C-spine) injury and immobilized with until clinical and radiographic studies can prove otherwise
• Minimize CSF leak– Bed flat– Never suction orally; never insert NG tube; never use Q-Tips in
nose/ears; caution patient not to blow nose
• Place sterile gauze/cotton ball around areaDefinitive Rx: • Measures to reduce ICP • Supportive management• Surgery
Pre-hospital care:• Patients with severe head injuries should be assumed to have
a cervical spine (C-spine) injury and immobilized with until clinical and radiographic studies can prove otherwise
• Minimize CSF leak– Bed flat– Never suction orally; never insert NG tube; never use Q-Tips in
nose/ears; caution patient not to blow nose
• Place sterile gauze/cotton ball around areaDefinitive Rx: • Measures to reduce ICP • Supportive management• Surgery
Head InjuryHead Injury
• Minor head trauma– Concussion : head injury with a temporary
loss of brain function concussion can cause a variety of physical, cognitive , and emotional symptoms.
Cause: Sudden acceleration and deceleration injury eg: Car accident, sports injury, bicycle accident etc
• Minor head trauma– Concussion : head injury with a temporary
loss of brain function concussion can cause a variety of physical, cognitive , and emotional symptoms.
Cause: Sudden acceleration and deceleration injury eg: Car accident, sports injury, bicycle accident etc
Head InjuryTypes of Head Injuries
Head InjuryTypes of Head Injuries
ConcussionPresentation:Physical-headache, LOC, Amnesia, s/s of
ICP(Cushing’s triad) , convulsions Cognitive : confusion, irritability,
behavioral changes
ConcussionPresentation:Physical-headache, LOC, Amnesia, s/s of
ICP(Cushing’s triad) , convulsions Cognitive : confusion, irritability,
behavioral changes
Head InjuryHead Injury
• Minor head trauma
– Postconcussion syndrome
• 2 weeks to 2 months
• Persistent headache
• Lethargy
• Personality and behavior changes
• Minor head trauma
– Postconcussion syndrome
• 2 weeks to 2 months
• Persistent headache
• Lethargy
• Personality and behavior changes
Head InjuryHead Injury
• Major head trauma
– Includes cerebral contusions and lacerations
– Both injuries represent severe trauma to the brain
• Major head trauma
– Includes cerebral contusions and lacerations
– Both injuries represent severe trauma to the brain
Head InjuryHead Injury
• Major head trauma– Contusion
• The bruising of brain tissue within a focal area that maintains the integrity of the pia mater and arachnoid layers associated with multiple micro-hemorrhages, small vessel bleed into brain tissue
– Lacerations• Involve actual tearing of the brain tissue• Intracerebral hemorrhage is generally
associated with cerebral laceration
• Major head trauma– Contusion
• The bruising of brain tissue within a focal area that maintains the integrity of the pia mater and arachnoid layers associated with multiple micro-hemorrhages, small vessel bleed into brain tissue
– Lacerations• Involve actual tearing of the brain tissue• Intracerebral hemorrhage is generally
associated with cerebral laceration
Head InjuryHead Injury
Cerebral Contusion Cerebral Laceration
Head InjuryPathophysiology
Head InjuryPathophysiology
• Diffuse axonal injury (DAI)
– Widespread axonal damage occurring after a mild, moderate, or severe TBI
– Seen in half the cases of head injury
– Process takes approximately 12-24 hours
• Diffuse axonal injury (DAI)
– Widespread axonal damage occurring after a mild, moderate, or severe TBI
– Seen in half the cases of head injury
– Process takes approximately 12-24 hours
Head InjuryPathophysiology
Head InjuryPathophysiology
• Diffuse axonal injury (DAI)
– Clinical signs: Level of Consciousness ICP
• Decerebration or decortication
• Global cerebral edema
• 90% regain consciousness from severe DAI
• Diffuse axonal injury (DAI)
– Clinical signs: Level of Consciousness ICP
• Decerebration or decortication
• Global cerebral edema
• 90% regain consciousness from severe DAI
Intracranial HemorrhageIntracranial Hemorrhage
Extra- axial hemorrhage
• Epidural hematoma
• Subdural hematoma-
Acute
Chronic
• Subarachnoid hemorrhage
Intra-axial hemorrhage
• Intra-parenchymal hemorrhage
• Intra-ventricular hemorrhage
Extra- axial hemorrhage
• Epidural hematoma
• Subdural hematoma-
Acute
Chronic
• Subarachnoid hemorrhage
Intra-axial hemorrhage
• Intra-parenchymal hemorrhage
• Intra-ventricular hemorrhage
Epidural hematomaEpidural hematoma
– Results from bleeding between the dura and the inner surface of the skull
– MC type of traumatic Intracranial bleed, rarely occurs spontaneously
– A neurologic emergency– Bleed is Venous or arterial origin
– Results from bleeding between the dura and the inner surface of the skull
– MC type of traumatic Intracranial bleed, rarely occurs spontaneously
– A neurologic emergency– Bleed is Venous or arterial origin
Epidural hematomaEpidural hematoma
Source of Bleed : Temperoparietal locus (most likely) - Middle meningeal artery
Frontal locus - anterior ethmoidal artery
Occipital locus - transverse or sigmoid sinuses
Vertex locus - superior sagittal sinus
Clinical Features: • LOC>>> Lucid Interval >> unconsciousness
• s/s of raised ICP
• Focal neurological deficit
• s/s of cerebral herniation
Source of Bleed : Temperoparietal locus (most likely) - Middle meningeal artery
Frontal locus - anterior ethmoidal artery
Occipital locus - transverse or sigmoid sinuses
Vertex locus - superior sagittal sinus
Clinical Features: • LOC>>> Lucid Interval >> unconsciousness
• s/s of raised ICP
• Focal neurological deficit
• s/s of cerebral herniation
Subdural hematomaSubdural hematoma
– Occurs from bleeding between the dura mater and arachnoid layer of the meningeal covering of the brain
– Source of bleed: Bridging veins; May be caused by an arterial hemorrhage
– Much slower to develop into a mass large enough to produce symptoms.
Cause: Acceleration-deceleration injury, direct trauma,
Risk factors: Elderly, dementia, alcoholics, shaken baby syndrome, pts on anticoagulants
– Occurs from bleeding between the dura mater and arachnoid layer of the meningeal covering of the brain
– Source of bleed: Bridging veins; May be caused by an arterial hemorrhage
– Much slower to develop into a mass large enough to produce symptoms.
Cause: Acceleration-deceleration injury, direct trauma,
Risk factors: Elderly, dementia, alcoholics, shaken baby syndrome, pts on anticoagulants
Subdural hematomaSubdural hematoma
– Acute subdural hematoma(<72hrs)• High mortality
• Associated with major direct trauma (Shearing Forces)
Clinical Features:
Headache, fluctuating LOC, confusion, dilated fixed pupil, deviated gaze
CT scan: hyperdense
– Acute subdural hematoma(<72hrs)• High mortality
• Associated with major direct trauma (Shearing Forces)
Clinical Features:
Headache, fluctuating LOC, confusion, dilated fixed pupil, deviated gaze
CT scan: hyperdense
Subdural hematomaSubdural hematoma
– Subacute subdural hematoma• Occurs within 4-21 days of the injury• Failure to regain consciousness may be an indicator
CT scan: Isodense or hypodense– Chronic subdural hematoma(>3wks)
• Develops over weeks or months after a seemingly minor head injury, probably from repeat minor bleeds
CT scan : hypodense
– Subacute subdural hematoma• Occurs within 4-21 days of the injury• Failure to regain consciousness may be an indicator
CT scan: Isodense or hypodense– Chronic subdural hematoma(>3wks)
• Develops over weeks or months after a seemingly minor head injury, probably from repeat minor bleeds
CT scan : hypodense
Epidural and Subdural HematomasEpidural and Subdural Hematomas
Fig. 55-15
Epidural Hematoma
Subdural Hematoma
Epidural and Subdural HematomasEpidural and Subdural Hematomas
Hematoma type Epidural Subdural
Location Between the skull and the dura Between the dura and the arachnoid
Involved vessel Temperoparietal (most likely) - Middle meningeal artery Frontal - anterior ethmoidal arteryOccipital - transverse or sigmoid sinusesVertex - superior sagittal sinus
Bridging veins
Symptoms Lucid interval followed by unconsciousness
Gradually increasing headache and confusion
CT appearance Biconvex lens- limited by suture lines
Crescent shaped- crosses suture lines
Fig. 55-15
Subarachnoid Hemorrhage Subarachnoid HemorrhageCauses:• Rupture of Berry aneurism(MCC)• Trauma (fracture at the base of the skull leading to internal
carotid aneurysm)• Amyloid angiopathy• Blood dyscrasias• Vasculitis
Clinical Features:• Explosive or thunderclap headache, “worst headache of my life”, • nausea and vomiting, decreased LOC or coma.• Signs of meningeal irritation
Causes:• Rupture of Berry aneurism(MCC)• Trauma (fracture at the base of the skull leading to internal
carotid aneurysm)• Amyloid angiopathy• Blood dyscrasias• Vasculitis
Clinical Features:• Explosive or thunderclap headache, “worst headache of my life”, • nausea and vomiting, decreased LOC or coma.• Signs of meningeal irritation
Intracerebral Hemorrhage (ICH)
Intracerebral Hemorrhage (ICH)
Intracranial hemorrhage is hemorrhage that occurs within the brain tissue itself; an intra-axial hemorrhage.
Two main types:
1)Intraparencymal hemorrahge- ICH extending into brain parenchyma; MCC- HTNsive vasculopathy
2)Intra-ventricular hemorrhage- ICH extending into ventricles; MCC –trauma
Causes:
Hypertensive vasculopathy(70-80%)
Ruptured AVM
Trauma
Blood dyscracias
Intracranial hemorrhage is hemorrhage that occurs within the brain tissue itself; an intra-axial hemorrhage.
Two main types:
1)Intraparencymal hemorrahge- ICH extending into brain parenchyma; MCC- HTNsive vasculopathy
2)Intra-ventricular hemorrhage- ICH extending into ventricles; MCC –trauma
Causes:
Hypertensive vasculopathy(70-80%)
Ruptured AVM
Trauma
Blood dyscracias
Intracerebral Hemorrhage (ICH)
Intracerebral Hemorrhage (ICH)
Clinical presentation: Rapidly progressive severe headache, building over several minutes, often accompanied by focal neurological deficits, nausea and vomiting, decreased level of consciousness.
S/S depend site of hemorrhage:
Basal ganglia/internal capsule - hemiparesis, dysphasia
Cerebellum - ataxia, vertigo
Pons - cranial nerve deficits, coma
Cerebral cortex - hemiparesis, hemisensory loss,
hemianopsia, dysphasia
Clinical presentation: Rapidly progressive severe headache, building over several minutes, often accompanied by focal neurological deficits, nausea and vomiting, decreased level of consciousness.
S/S depend site of hemorrhage:
Basal ganglia/internal capsule - hemiparesis, dysphasia
Cerebellum - ataxia, vertigo
Pons - cranial nerve deficits, coma
Cerebral cortex - hemiparesis, hemisensory loss,
hemianopsia, dysphasia
ComplicationsComplications
• Neurological deficits or death• Seizures• Obstructive Hydrocephalus• Spasticity• Urinary complications• Aspiration pneumonia• Cushing’s ulcer• Neuropathic pain• Deep venous thrombosis• Pulmonary emboli• Cerebral herniation
• Neurological deficits or death• Seizures• Obstructive Hydrocephalus• Spasticity• Urinary complications• Aspiration pneumonia• Cushing’s ulcer• Neuropathic pain• Deep venous thrombosis• Pulmonary emboli• Cerebral herniation
Cerbral HerniationCerbral Herniation
Brain herniation is a deadly side effect of very high intracranial pressure that occurs when a part of the brain is squeezed across structures within the skull.
“Brain herniation represents mechanical displacement of normal brain relative to another anatomic region secondary to mass effect from traumatic, neoplastic, ischemic, or infectious etiologies. “
Brain herniation is a deadly side effect of very high intracranial pressure that occurs when a part of the brain is squeezed across structures within the skull.
“Brain herniation represents mechanical displacement of normal brain relative to another anatomic region secondary to mass effect from traumatic, neoplastic, ischemic, or infectious etiologies. “
Cerbral HerniationCerbral Herniation
Supratentorial herniation
1. Uncal
2. Central (transtentorial)
3. Cingulate (subfalcine)
4. Transcalvarial
Infratentorial herniation
5. Upward (upward cerebellar or upward transtentorial)
6. Tonsillar (downward cerebellar)
Cingulate HerniationCingulate Herniation
The most common type, the innermost part of the frontal lobe is scraped under part of the falx cerebri, the dura mater at the top of the head between the two hemispheres of the brain.
Cingulate herniation can be caused when one hemisphere swells and pushes the cingulate gyrus by the falx cerebri.
Cingulate herniation is frequently believed to be a precursor to other types of herniation
The most common type, the innermost part of the frontal lobe is scraped under part of the falx cerebri, the dura mater at the top of the head between the two hemispheres of the brain.
Cingulate herniation can be caused when one hemisphere swells and pushes the cingulate gyrus by the falx cerebri.
Cingulate herniation is frequently believed to be a precursor to other types of herniation
Uncal HerniationUncal Herniation
common subtype of cerebral herniation following raised ICP
Innermost part of the temporal lobe, the uncus, can be squeezed so much that it moves towards the tentorium and puts pressure on the brainstem, most notably the midbrain
Clinical feature:
• Compression of I/L CN III- I/L fixed dilted pupil
• Compression of I/L PCA- C/L homonymous hemianopsia
• Compression of C/L crus cerebri- I/L hemiparesis
• Duret hemorrhage
common subtype of cerebral herniation following raised ICP
Innermost part of the temporal lobe, the uncus, can be squeezed so much that it moves towards the tentorium and puts pressure on the brainstem, most notably the midbrain
Clinical feature:
• Compression of I/L CN III- I/L fixed dilted pupil
• Compression of I/L PCA- C/L homonymous hemianopsia
• Compression of C/L crus cerebri- I/L hemiparesis
• Duret hemorrhage
Diagnostic Studies Diagnostic Studies
CT scan –• A GCS score less than 15 after blunt
head trauma warrants a patient with no intoxicating consideration of an urgent CT scan.
CT scan –• A GCS score less than 15 after blunt
head trauma warrants a patient with no intoxicating consideration of an urgent CT scan.
CT findingsCT findings
Fig. 55-15
Epidural Hematoma Subdural Hematoma
CT findingsCT findings
Fig. 55-15
Subarachnoid hemorrhage Intracerebral hematoma
Diagnostic Studies Diagnostic Studies
• MRI – superior for demonstrating the size of an acute subdural hematoma.
• Cerebral angiogram if hemorrhage is confirmed (not necessary in case of classic hypertensive hemorrhage
• Cervical spine X-ray• EEG• Lumbar Pucture
• MRI – superior for demonstrating the size of an acute subdural hematoma.
• Cerebral angiogram if hemorrhage is confirmed (not necessary in case of classic hypertensive hemorrhage
• Cervical spine X-ray• EEG• Lumbar Pucture
Management Management
1) Supportive Measures:
• Endotracheal intubation for patients with decreased level of consciousness and poor airway protection.
• Cautiously lower blood pressure to a MAP less than 130 mm Hg, but avoid excessive hypotension.[10]
• Rapidly stabilize vital signs, and simultaneously acquire emergent CT scan.
• Maintain euvolemia, using normotonic rather than hypotonic fluids, to maintain brain perfusion without exacerbating brain edema
• Avoid hyperthermia.
• Facilitate transfer to the operating room or ICU.
1) Supportive Measures:
• Endotracheal intubation for patients with decreased level of consciousness and poor airway protection.
• Cautiously lower blood pressure to a MAP less than 130 mm Hg, but avoid excessive hypotension.[10]
• Rapidly stabilize vital signs, and simultaneously acquire emergent CT scan.
• Maintain euvolemia, using normotonic rather than hypotonic fluids, to maintain brain perfusion without exacerbating brain edema
• Avoid hyperthermia.
• Facilitate transfer to the operating room or ICU.
Management Management
2) Decrease cerebral edema: • Modest passive hyperventilation to reduce PaCO2• Mannitol, 0.5-1.0 gm/kg slow iv push
• Furosemide 5-20 mg iv
• Elevate head 20-30 degrees, avoid any neck vein compression
• Sedate and paralyze if necessary with morphine and vecuronium (struggling, coughing etc will elevate intracranial pressure)
2) Decrease cerebral edema: • Modest passive hyperventilation to reduce PaCO2• Mannitol, 0.5-1.0 gm/kg slow iv push
• Furosemide 5-20 mg iv
• Elevate head 20-30 degrees, avoid any neck vein compression
• Sedate and paralyze if necessary with morphine and vecuronium (struggling, coughing etc will elevate intracranial pressure)
Management Management 3) Surgical Evacuation of hematoma:• No surgical intervention if collection <10ml
Indication of surgical decompression: • The GCS score decreases by 2 or more points between the time of injury and hospital
evaluation• The patient presents with fixed and dilated pupils• The intracranial pressure (ICP) exceeds 20 mm Hg
Exception : In Subdural hematoma with GCS=15- hematoma >10mm ,or >5mm midline shift ----
requires Surgical decompression
SAH: whn a cerebral aneurysm is identified on angiography, clipping and coiling is done to prevent re-bleed
3) Surgical Evacuation of hematoma:• No surgical intervention if collection <10ml
Indication of surgical decompression: • The GCS score decreases by 2 or more points between the time of injury and hospital
evaluation• The patient presents with fixed and dilated pupils• The intracranial pressure (ICP) exceeds 20 mm Hg
Exception : In Subdural hematoma with GCS=15- hematoma >10mm ,or >5mm midline shift ----
requires Surgical decompression
SAH: whn a cerebral aneurysm is identified on angiography, clipping and coiling is done to prevent re-bleed
ManagementManagement
Sugical Decompression contd.. Types:
• Burr-hole • Craniotomy- bone flap is temporarily removed from
the skull to access the brain• Craniectomy – in which the skull flap is not immediately
replaced, allowing the brain to swell, thus reducing intracranial pressure
• Cranioplasty - surgical repair of a defect or deformity of a skull.
Sugical Decompression contd.. Types:
• Burr-hole • Craniotomy- bone flap is temporarily removed from
the skull to access the brain• Craniectomy – in which the skull flap is not immediately
replaced, allowing the brain to swell, thus reducing intracranial pressure
• Cranioplasty - surgical repair of a defect or deformity of a skull.
ManagementManagement4) Medical therapy:
• Antihypertensives - reduce blood pressure to prevent exacerbation of intracerebral hemorrhage in hypertensive encephalopathy. Eg Nicardipine, labetolol; CCB help relieve vasospasm in SAH and decrease further damage
• Diuretics - Mannitol, CAI• Anticonvulsants – reduce frequency of seizures and prophylaxis of
seizures eg: Fosphenytoin• Antipyretics- to Rx fever and pain relief eg: Acetaminophene• Antidote-
VitK/FFP for warfarin overdose; protamine for heparin overdose
• Antacids- prophylaxis for Cushing’s gastric ulcer eg: Famotidin • Glucorticoids may help reduce the head and neck ache caused by the
irritative effect of the subarachnoid blood.
4) Medical therapy:
• Antihypertensives - reduce blood pressure to prevent exacerbation of intracerebral hemorrhage in hypertensive encephalopathy. Eg Nicardipine, labetolol; CCB help relieve vasospasm in SAH and decrease further damage
• Diuretics - Mannitol, CAI• Anticonvulsants – reduce frequency of seizures and prophylaxis of
seizures eg: Fosphenytoin• Antipyretics- to Rx fever and pain relief eg: Acetaminophene• Antidote-
VitK/FFP for warfarin overdose; protamine for heparin overdose
• Antacids- prophylaxis for Cushing’s gastric ulcer eg: Famotidin • Glucorticoids may help reduce the head and neck ache caused by the
irritative effect of the subarachnoid blood.
Preventive MeasuresPreventive Measures
Health Promotion
• Prevent car and motorcycle accidents
• To Wear safety helmets
Health Promotion
• Prevent car and motorcycle accidents
• To Wear safety helmets
RehabilitationRehabilitation
Ambulatory and Home Care
• Nutrition
• Bowel and bladder management
• Spasticity
• Dysphagia
• Seizure disorders
• Family participation and education
Ambulatory and Home Care
• Nutrition
• Bowel and bladder management
• Spasticity
• Dysphagia
• Seizure disorders
• Family participation and education
References:
• Harrison's Principles of Internal Medicine
• Medscape Reference http://emedicine.medscape.com
• US National Library of Medicine National Institutes of Health http://www.ncbi.nlm.nih.gov
References:
• Harrison's Principles of Internal Medicine
• Medscape Reference http://emedicine.medscape.com
• US National Library of Medicine National Institutes of Health http://www.ncbi.nlm.nih.gov
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