MILD HEAD INJURY (MHI)
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Transcript MILD HEAD INJURY (MHI)
MILD HEAD INJURY (MHI)
Bernard Foley
Auckland Hospital
Emergency Department
6th October 2001
SCENARIO 1
A 15-year-old boy is brought to your clinic by
his mother
He had been out rollerblading and was
observed to fall and hit his head
He was not knocked out
He complains of mild headache
SCENARIO 2
A 23-year-old man presents by ambulance
He had been drinking at a pub and
subsequently assaulted 1 hour ago
GCS 14, PERLA, No focal neurology or signs
of skull fracture
SCENARIO 3
A 45-year-old woman presents following an
RTC
Briefly K.O.’D at the scene
GCS 12 (E3,M5,V4)
PERLA
No focal neurology
Large haematoma over right temple region
MHI EPIDEMIOLOGY
@ 130 MILD HEAD INJURIES/100,000/yr.
@ 100/MONTH AT AUCKLAND ED
MALE 2 : 1 FEMALE
PEAK AGE 15-24 YEARS
LOWEST RATES AGE 35-65
ALCOHOL > 17mmol/L PRESENT IN 2/3rds
OF THOSE TESTED FOR IT
MHI CAUSES
ROAD CRASH
FALLS
ASSAULT
SPORTS
40%
20%
15%
12%
CHILDREN CONSIDER NAI
MHI DIAGNOSES
CONCUSSION
FACIAL/SKULL FRACTURE
CONTUSION
HAEMORRHAGE
80%
10%
5%
1%
CONCUSSION
Transient alteration in cerebral function
Usually associated with L.O.C.
Thought to be due to disturbance in reticular
activating system function
No structural brain injury
May lead to post-concussive syndromes
POST CONCUSSION SYMDROMES
Typically mild headache and cognitive
disturbances
Confusion,nausea,dizziness,fatigue
Typically last 1-2 days
May last months
If symptoms last >6 weeks should be seen by
head injury specialist
CONTUSION
Bruising of brain substance
Morbidity relates to size and site of contusion
Commonly occur in frontal and temporal lobes
INTRACRANIAL BLEEDING
Extradural
Subdural
Intracerebral
Subarachnoid
Intraventricular
DIFFUSE AXONAL INJURY
Shearing and rotational forces resulting in
major structural and functional damage at a
microscopic level.
CT scan often appears normal
Pathogenesis unclear
MINIMAL HEAD INJURY
GCS 15 and…
No or only mild headache and nausea
No L.O.C.
No antegrade amnesia
No seizure
No vomiting
2< AGE< 65
Likelihood of CT abnormality essentially 0%
MILD HEAD INJURY
GCS 14 or 15 and….
Any L.O.C., seizure or vomiting
Intoxication, Coagulopathy
Clinical skull fracture or large scalp
haematoma
Focal neurological abnormality
Abnormal pupillary reactions
MILD HEAD INJURY 2
Likelihood of abnormal CT @ 10%
Neurosurgical intervention <1%
MODERATE HEAD INJURY
GCS 9-13
Likelihood of abnormal CT 40%
Neurosurgical intervention @ 8%
Mortality 20%
Long term disability 50%
SEVERE HEAD INJURY
GCS <9
Mortality 40%
Long term disability >90%
HISTORY
Accident events
Duration of L.O.C.
Seizure?
Amnesia
Nausea/vomiting
Drug use
Coexistent medical problems/allergies etc.
PHYSICAL EXAMINATION
Primary survey
GCS
Check/protect C-spine
Pupils
Signs of skull/ basal skull fracture
Focal neurology
Other injuries
NEUROLOGICAL OBSERVATIONS
No good evidence of usefulness
No evidence regarding duration
4-hours v 24-hours
Possibly useful if no imaging available
INVESTIGATIONS
Blood tests
Consider Glucose, U&E’s, FBC, Group and Hold
Skull x-rays
No
Perhaps in suspected depressed skull fracture
CT head
Investigation of choice
Considerable debate about who should be scanned
CT HEAD - PRO’S
ACCURATE DIAGNOSIS OF
INTRACRANIAL INJURY
AIDS SURGICAL PLANNING/ TRIAGE
MAY IDENTIFY AREAS WHERE INJURY
OTHERWISE OCCULT
MAY IDENTIFY INJURY WHERE NOT
SUSPECTED
MOST STUDIES IN LEVEL 1 TRAUMA CENTRES
CT HEAD CONS
EXPENSE
AVAILABILITY
MAY REQUIRE TRANSPORT TO ANOTHER
FACILITY
RADIATION EXPOSURE
PATIENT ISOLATION
?SEDATION REQUIRED esp. KIDS
CANADIAN CT HEAD RULES
LANCET 2001;357 1391-96
ELIGIBILITY
Blunt trauma within 24 hours
Witnessed L.O.C. or definite amnesia or
disorientation
GCS 13 or greater
EXCLUSIONS
Obvious penetrating injury, depressed skull
fracture or focal neurology on exam
CANADIAN HEAD CT RULES
5 HIGH RISK PREDICTORS
1) GCS < 15, 2 hours after injury
2) Suspected open or depressed skull fracture
3) Any sign of basal skull fracture
4) Vomiting (2x or more)
5) Age > 65
CANADIAN HEAD CT RULES
2 Additional medium risk factors
Amnesia >30 minutes before event
Dangerous mechanism of injury
Fall > 3 feet or 5 stairs
Pedestrian struck by motor vehicle
Ejected from car
CANADIAN HEAD CT RULES
USING 5 HIGH-RISK CRITERIA
100% sensitivity (identifying those dying or
requiring neurosurgery
Specificity 69%
USING ABOVE + 2 MEDIUM RISK
CRITERIA
98.4% sensitivity and 54% specificity
WHO TO SCAN
AGE > 65
INTOXICATED
SEVERE HEADACHE
VOMITING
SEIZURE
SIGNS OF SKULL FRACTURE
FOCAL NEUROLOGY
? ALL LATE PRESENTERS
MANAGEMENT
Analgesia
Attend to other injuries
? Tetanus prophylaxis
? Observation
Referral if requires inpatient care
Documentation (incl.. ACC)
MANAGEMENT (SEVERE INJURY)
Discuss with hospital/neurosurgeon
Oxygen/ ? Intubate and ventilate
IV access
Treat hypotension with fluids
Protect spine
Consider neuroprotection
Role of mannitol and hyperventilation
controversial
DISCHARGE
ALL MINIMAL HEAD INJURY
If sober and competent observer
ALL MHI WITH NORMAL CT SCAN
Unless other injuries
All require competent supervision
ADMIT ALL MODERATE/SEVERE
ADMIT ALL WITH ABNORMAL CT
DISCHARGE ADVICE
Written advice
Explain and give to observer
67% will carry out instructions correctly
If given to patient to arrange <20%
ANNALS OF EMRGENCY MEDICINE
15:2 FEB 1986
DISCHARGE ADVICE
EXPLAIN POST CONCUSSION
SYMPTOMS
REST AND TIME OFF WORK
ANALGESIA
RETURN IF ANY CONCERNS
AVOID
Alcohol
Driving? Major decisions for 24 hours
Further injury for 3 weeks