Post on 15-Aug-2015
Traumatic Brain InjuryRobert Lieberson, MD, FACS
Brain, Spine, and Peripheral Nerve Surgery
Learning Objectives
At the conclusion of this session, you will be able to:
1. appreciate the demographics of TBI;
2. discuss the approach to the TBI patient;
3. describe the examination and the evaluation of the TBI patient;
4. recognize many of the common injuries;
5. be familiar with some of the medical treatment options;
6. be aware of some of the surgical options; and,
7. understand the prognosis of TBI.
1. Demographics of TBI
52,000 Deaths
275,000 Hospitalization
s
1,365,000 Emergency Room Visits
An unknown number receive alternate care or no care
789,925
Men
574,870
Women
At least 1.7 million TBI per
year in USA
By cause All ages
Assault10%
Struck By/
Against17%
Unknown/Other21%
Motor Vehicle-Traffic17%
Falls35%
Frequency by age
0-4 5-9 10-14 15-19 20-24 25-34 35-44 45-54 55-64 65-74 75 +0
200
400
600
800
1000
1200
1400
Per
100,0
00
2. Approach to the TBI Patient
Schematic behavior ("on autopilot“) versus attentional behavior (problem-solving)
Failures of schematic behavior are “slips” (lapses in concentration, distractions, or fatigue).
Failures of attentional behavior are “mistakes” (lack of training or experience).
In health care, most errors are caused by “slips.”
Checklists reduce the risk of “slips.”
Ghajar J, Hariri RJ, Narayan RK, Iacono LA, Firlik K, Patterson RH.
Survey of critical care management of comatose, head-injured patients in the United States.
Critical Care Med. 1995 Mar;23(3):560-7.
Adherence to the TBI guidelines improves outcomes, but in a survey of ICUs in 45 states:
Only 28% of neurosurgeons routinely measure ICP
83% still use hyperventilation and osmotic diuretics
29% still maintain PaCO2 < 25 mm Hg
44% still use corticosteroids
Advanced Trauma Life Support Guidelines for the Management of
Severe Traumatic Brain Injury, 3rd Edition, 2007
Guidelines for the Surgical Management of Traumatic Brain Injury, 2006
Guidelines for Management and Prognosis of Severe Traumatic Brain Injury, 2000
Guidelines for the Acute Medical Management of Severe Traumatic Brain Injury in Infants, Children, and Adolescents, 2nd Edition, 2012
Start with Advanced Trauma Life Support Primary Survey
ABCDEs
Secondary Survey GCS from the top down (EVM) General examination from the top down Neuro examination from the top down
Tertiary Survey PMH, FH, SH, Meds, Allergies, ROS
If the patient deteriorates, return to the primary survey and start over
3. Evaluation of the TBI Patient
ATLS primary survey
ABCDE (different than the ABCs of CPR) Airway (remember the c-spine precautions) Breathing (exclude pneumothorax,
tamponade, etc) Circulation (and also control hemorrhage) Disability/neurological (AVPU [alert, verbal,
painful, unresponsive], pupils and spinal cord (GCS goes with secondary survey)
Environmental (remove clothes, correct/prevent hypothermia)
ATLS Secondary Survey
Complete history Top down examination (including GCS) X-rays and lab
Focused abdominal sonogram for trauma (FAST exam)
Evaluates pericardium, right and left upper abdomen and pelvic region for blood
CBC, BMP, coags, type and screen, tox, ABG, pregnancy
Non-contrast CTs of C-spine, chest, abdomen, and pelvis
Maintain PaO2 > 60 mm Hg and SBP ≥ 65 mm Hg
ATLS Tertiary Survey
Careful and complete examination, serial assessments, rate of delayed diagnosis can be 10%
If patient deteriorates, return and repeat the primary survey
History Events surrounding the
accident Seatbelt, helmet, position in
motor vehicle, direction of impact, speed, damage to windshield or steering wheel
Assess for EtOH or illicit drugs Drugs may confound the
examination
Was there a seizure at the time of the accident
HistoryMechanism of Injury
Rotational most likely to cause shearing
Lateral and AP cause coup and contra-coupand subdurals
Local injury to the temporal bone causes epidurals
Examination—General Head
Scalp lacerations
May be associated with significant blood loss
Depressed skull fracture (convexity fractures)
Most skull fractures non-displaced
CSF rhinorrhea or otorrhea, raccoon eyes, Battle’s sign (basilar skull fractures)
Significant head injuries can occur without external stigmata
Spine
Step-off
Tenderness
Passive rewarming
Hypothermia may confound the neurological examination
Examination—Glasgow Coma Scale
Top down (EVM); least categories to most
GCS 13-15 is mild; GCS 9-12 is moderate; GCS 3-8 is severe/coma
Eyes
Verbal
Motor
Top Down
4
5
6
Neurological Examination
A complete neurological examination on every patient (organized from top down) Mental status Cranial Nerves (including pupils) Motor (rate power from 0/5 to 5/5) Sensory (light touch and pin prick) Reflexes (0, 1, 2, 3, 4) Coordination/Gait
Post Traumatic Amnesia
Retrograde versus antegrade
Indications for CT
Mild TBI (GCS ≥ 13) New Orleans Criteria
No CT if GCS 15, + LOC, no neuro deficit, age > 3 years
CT if headache, vomiting, seizure, intoxication, short term memory deficit, age > 60, injury above the clavicle
Canadian CT Head rule No CT if GCS 13-15, + LOC, no neuro deficit, no seizure, no
anticoagulation, age > 16 years
CT if:
High risk—GCS < 15 after 2 hours, suspected convexity or basilar skull fracture, vomiting ≥ 2 times, or age ≥ 65; or,
Medium risk—retrograde amnesia > 30 minutes, severe mechanism (pedestrian vs. car, ejected from car, or fall from > 1 m or five stairs)
Indications for CT
Moderate TBI (GCS 9-12) or Severe TBI (GCS ≤ 8) All get a head CT
CT is positive in 93% of patients with a severe TBI
A negative CT does not guarantee a “favorable” prognosis
Obliteration of basal cisterns associated with “unfavorable” outcomes in 97% of cases
4. Recognize Common Injuries
Layers from outside to inside
Scalp Contusion
Caput succedaneum
Subgaleal hematoma
Subperiosteal hematoma or cephalohematoma
Subgaleal versus subperiosteal hematoma
Epidural hematoma
Epidural hematoma
Subdural hematoma
Subdural hematoma
Subarachnoid Hemorrhage
Cerebral contusion
Cerebral contusion
Intraventricular hemorrhage
Axonal shearing injuries
Through and through gunshot wound
Marshall Classification of CT findings
Diffuse injury I—No visible pathology on CTDiffuse injury II—Cisterns present, midline
shift < 5 mm, no high-density lesion > 2.5 cm
Diffuse injury III—Cisterns compressed or absent, no high-density lesion > 2.5 cm
Diffuse injury IV—Midline shift > 5 mm, no high-density lesion > 2.5 cm
Evacuated mass—Any lesion surgically evacuated
Non-evacuated mass—High-density lesion > 2.5 cm but not surgically evacuated
Traumatic dissections
5. Medical Treatment Options Primary Injury
Occurs at the moment of trauma
Contusion, damage to blood vessels, axonal shearing, blood brain barrier changes, fractures, and meningeal injury
Secondary Injury Begins in the hospital (causes significant disability, preventable)
Ischemia and cerebral hypoxia (due to hypotension and impaired autoregulation)
Cerebral edema (raised intracranial pressure, brain herniation)
Metabolic changes such as hypercapnia and acidosis
Infection (meningitis, brain abscess)
Release of neurotransmitters (excitotoxicity)
Viscous Cycles (edema causes more ischemia which causes more edema)
Systemic complications (pneumonia, DVT)
TBI Guidelines 2007
Three classes of evidence
Class I: Relevant screening test; credible reference standard; reference standard independent of screening test; reliability of test assessed; few indeterminate results; large number of patients.
Class II: Relevant screening test; reasonable although not best standard; standard independent of screening test; moderate number of patients.
Class III: Has fatal flaws; inappropriate reference standard; screening tests improperly administered; small number of patients.
Three levels of recommendation (based on class of evidence, highest level with at least one recommendation given)
15 categories, only 14 stated “level of evidence”
Level I: 1/14 (steroid use)
Level II: 10/14 (BP, Mannatol, Abx, ICP monitoring, ICP threshold, CPP, anesthetics, nutrition, Sz meds, hyperventilation)
Level III: 3/14 (hypothermia, DVT, brain O2 monitoring)
TBI Guidelines (I to III)
I. Blood Pressure and Oxygenation B. Level II—Hypotension (SBP < 90 mmHg) should be avoided.
C. Level III--Hypoxia (PaO2 < 60 mmHg or O2 saturation < 90%) should be avoided.
II. Hyperosmolar Therapy B. Level II--Mannitol is effective to treat ICP. Doses of 0.25 to 1
g/kg.
C. Level III--Restrict mannitol use prior to ICP monitoring to patients with signs of herniation or progressive neurological deterioration.
III. Prophylactic Hypothermia C. Level—Better outcomes with temperatures of 32–33°C for > 48
hours. Difficult to do.
TBI Guidelines (IV to VII)
IV. Infection Prophylaxis
B. Level II--Periprocedural antibiotics for intubation should be administered. Early tracheostomy should be performed to reduce ventilator days.
C. Level III--Routine ventricular catheter exchange or prophylactic antibiotic use is not recommended.
V. Deep Vein Thrombosis Prophylaxis
C. Level III--Compression stockings are recommended. Low molecular weight heparin (LMWH) or low dose unfractionated heparin should be used, however, there is an increased risk of hemorrhage. There is no clear preferred agent.
VI. Indications for Intracranial Pressure Monitoring
B. Level II--Monitor Intracranial pressure (ICP) in all salvageable patients with a severe TBI (GCS 3–8) and an abnormal CT scan.
C. Level III--ICP monitoring is indicated in patients with severe TBI with a normal CT scan if two or more of the following: age over 40 years, unilateral or bilateral motor posturing, or SBP < 90 mm Hg.
VII. Intracranial Pressure Monitoring Technology
A ventricular catheter and an external strain gauge is the most accurate, low-cost, and reliable method. It can be recalibrated. Strain gauge devices provide similar benefits, but cost more and cannot be recalibrated.
TBI Guidelines (VIII to X)
VIII. Intracranial Pressure Thresholds
B. Level II—Treat ICPs above 20 mm Hg.
C. Level III—Use a combination of ICP values, clinical findings, and CT findings to guide treatment (common sense).
IX. Cerebral Perfusion Thresholds
B. Level II—Ovrly aggressive attempts to keep CPP > 70 mm Hg with fluids and pressors should be avoided because of the risk of adult respiratory distress syndrome (ARDS).
C. Level III--CPP of < 50 mm Hg should be avoided. The CPP value to target lies within the range of 50–70 mm Hg.
X. Brain Oxygen Monitoring and Thresholds
C. Level III—Maintain jugular venous saturation > 50% or brain tissue oxygen tension >15 mm Hg.
TBI Guidelines (XI to XV)
XI. Anesthetics, Analgesics, and Sedatives B. Level II--Prophylactic barbiturates not recommended. Barbiturates for ICP
refractory to all other treatment helpful but cause significant morbidity.
XII. Nutrition B. Level II--Full caloric replacement by day 7.
XIII. Antiseizure Prophylaxis B. Level II—Prophylactic, long-term anti-epileptics not recommended. Anticonvulsants
decrease early seizures but early seizures not associated with worse outcomes.
XIV. Hyperventilation B. Level II--Prophylactic hyperventilation (PaCO2 < 25 mm Hg) is dangerous.
C. Level III--Temporizing measure only. Most harmful early when CBF most reduced.
XV. Steroids A. Level I—Steroids are not recommended—cause increased mortality.
This is the only level II recommendation.
Summary
Intubate if: Poor airway protection or
GCS ≤ 8
Extubate early
Measure ICP if: GCS ≤ 8, abnormal CT GCS ≤ 8, nl CT but over
40, posturing, or low BP
PaO2 > 60 mmHG or O2 Sat > 90%
PaCO2 = 35 to 40 mm HG
Keep SBP > 90 and CPP 50-70 A single episode of
hypotension doubles mortality
Avoid hypotonic solutions (LR or ½ NSS)
Avoid hyperglycemia
Mannitol Signs of herniation
or progressive deterioration not due to extracranial causes
Dose 0.25 to 1 g/Kg Avoid before ICP
monitoring Avoid if hypotensive
Hypothermia QUESTIONABLE.
Steroids NOT helpful.
Anticonvulsants NOT for prophylaxis.
Antibiotics NOT for prophylaxis.
Hyperventilation NOT advised.
Full caloric replacement early.
DVT prophylaxis (SCDs, +/- anticoagulation).
Avoid high dose Propofol.
Barbiturates only in desperation.
Summary
TBI Guidelines Summary
Monitor ICP in all “severe” head injury patients (GCS ≤ 8) with an abnormal CT.
Monitor ICP in all “severe” head injury and a normal CT if two or more of the following:Age ≥ 40 years;Systolic blood pressure ≤ 90 mm Hg; and,Unilateral or bilateral posturing.
ICP and Compliance (closed box model)
Brain
Arterial Blood
Venous Blood
CSF
ECF
140 to 270 cc of CSF (25 in the ventricles)
1050 to 1150 cc of
brain
200 cc of ECF
100 cc of venous blood
50 cc of arterial blood
Mannitol
Ventricular
Drainage
Hyper- ventilati
on
ICP and Compliance
Brain
Arterial Blood
Venous Blood
CSF
ECF
Brain
Arterial Blood
Venous Blood
CSF
ECF
Subdural Hematoma
ICP and Compliance
Brain
Arterial Blood
Venous BloodCSF
ECF
Subdural Hematoma
ICP and Compliance
Brain
Arterial BloodVenous Blood
CSF
ECFSubdural
Hematoma
ICP and Compliance
Basal Cisterns
Herniation1.Subfalcine2.Transtentorial3.Uncal4.Transforaminal5.Upward
(Posterior Fossa)
6.Through a cranial defect
Cerebral Perfusion Pressure
CPP = MAP - ICPCerebral Perfusion Pressure is MAP minus
ICP. If MAP is 90 and ICP is 20, CPP is 70.CPP should be 50 to 70 mmHg.CPP over 70—ARDS more likely.CPP less than 50—No brain perfusion!
Objectives of ICP Monitoring
Maintain cerebral perfusion (and therefore oxygenation)
Remove CSF (if possible)Avoid secondary injury
ICP Monitoring Technology
A ventricular catheter and external strain gauge are the most accurate, reliable, and method of monitoring.
Ventriculostomies allow CSF Drainage.
ICP Monitoring Technology
Other ICP Monitors
Convenient, fast, accurate.
Cannot be recalibrated after insertion, and are expensive ($6,000 to $10,000).
6. Surgical Management of TBI 2006
Addresses Four Classes of
Lesion Epidural Hematomas Subdural Hematomas Contusions (Parenchymal
Lesions) Posterior Fossa Mass Lesions
Surgical Management of Epidurals
Indications for Surgery An epidural over 30 cm3 should be removed regardless of the GCS
score.
An epidural less than 30 cm3 and with less than a 15-mm thickness and with less than a 5-mm midline shift and with a GCS score greater than 8 without focal deficit can be managed nonoperatively but need serial scans and close follow-up.
Timing Patients with an acute epidural in coma with anisocoria need surgery
immediately.
Methods Craniotomy.
Exceptions Venous epidurals.
How do you determine volume on CT
Kothari, et al, 1996.
Find largest diameter (call it A)
Find diameter at 90 degrees to A (call it B)
Count the CT slices where the clot is seen to find the depth (call that C)
The volume is:
In a 30 cc lesion, the average value of A, B, and C is about 4 cm or 1½ inches
How do you measure shift on CT?
15 mm
How do you remove skull
Surgical Management of Epidurals
Surgical Management of Epidurals
Surgical Management of Subdurals
Indications for Surgery An acute subdural 10 mm thick or a midline shift over 5 mm should be removed
regardless of the GCS score.
• All patients with acute SDH in coma (GCS score less than 9) should undergo intracranial pressure (ICP) monitoring.
• A comatose patient (GCS score less than 9) with an SDH less than 10-mm thick and a midline shift less than 5 mm should undergo surgical evacuation of the lesion if the GCS score decreased between the time of injury and hospital admission by 2 or more points on the GCS and/or the patient presents with asymmetric or fixed and dilated pupils and/or the ICP exceeds 20 mm Hg.
Timing Patients with an acute subdural in coma with anisocoria need surgery immediately.
Methods Craniotomy
Surgery—subdural hematoma
Surgery—subdural hematoma
Surgery—subdural hematoma
Surgical Management of Contusions
Indications
Patients with parenchymal mass lesions and signs of progressive neurological deterioration referable to the lesion, medically refractory intracranial hypertension, or signs of mass effect on computed tomographic (CT) scan should be treated operatively.
Patients with Glasgow Coma Scale (GCS) scores of 6 to 8 with frontal or temporal contusions greater than 20 cm3 in volume with midline shift of at least 5 mm and/or cisternal compression on CT scan, and patients with any lesion greater than 50 cm3 in volume should be treated operatively.
Patients with parenchymal mass lesions who do not show evidence for neurological compromise, have controlled intracranial pressure (ICP), and no significant signs of mass effect on CT scan may be managed nonoperatively with intensive monitoring and serial imaging.
Timing and Methods
Craniotomy with evacuation of mass lesion is recommended for those patients with focal lesions and the surgical indications listed above, under Indications.
Bifrontal decompressive craniectomy within 48 hours of injury is a treatment option for patients with diffuse, medically refractory posttraumatic cerebral edema and resultant intracranial hypertension.
Decompressive procedures, including subtemporal decompression, temporal lobectomy, and hemispheric decompressive craniectomy, are treatment options for patients with refractory intracranial hypertension and diffuse parenchymal injury with clinical and radiographic evidence for impending transtentorial herniation.
Surgery—parenchymal lesions
Indications Expanding lesions with progressive
deterioration
Medial temporal lesions particularly dangerous
> 20 mL volume
≥ 5 mm shift
Avoid surgery if NO neurological deficit and ICP controlled
Serial imaging Decompressive craniectomy
controversial
Surgical Management of Posterior Fossa Lesions
Indications
• Patients with mass effect on computed tomographic (CT) scan or with neurological dysfunction or deterioration referable to the lesion should undergo operative intervention. Mass effect on CT scan is defined as distortion, dislocation, or obliteration of the fourth ventricle; compression or loss of visualization of the basal cisterns, or the presence of obstructive hydrocephalus.
• Patients with lesions and no significant mass effect on CT scan and without signs of neurological dysfunction may be managed by close observation and serial imaging.
Timing
• In patients with indications for surgical intervention, evacuation should be performed as soon as possible because these patients can deteriorate rapidly, thus, worsening their prognosis.
Methods
• Suboccipital craniectomy is the predominant method reported for evacuation of posterior fossa mass lesions, and is therefore recommended.
Surgery—posterior fossa lesions
Surgery—depressed skull fracture
Indications
In driven fragments increase seizure risk
Open fractures increase infection risk
Surgery—decompressive craniectomy
7. Prognosis
Glasgow Outcome Score (GOS)
2 MD Moderate disability (disabled but indeependant)—travel by public transportation, can work in sheltered setting (exceeds mere ability to perform “ADLs”).
3 SD Severe disability (conscious but disabled)—dependent for daily support (may be institutionalized, but this is not a criteria).
4 PVS Persistent vegetative state—unresponsive and speechless; after 2-3 weeks may open eyes and have sleep/wake cycles.
5 D Death—most deaths from primary head injury occur within 48 hours.
Glasgow Outcome Score-Extended (GOS-E) Reversed the numbers
Added “lower” and “upper” to the three intermediate categories
Prognosis of TBI 2000
Relatively few features have been found to contain most of the prognostic information.
Patient Age Severity of Injury
Difficult to quantify
Intracranial pressure Not always measured
Computed tomography (CT)
Prognosis of TBI 2000
Glasgow Coma Score (severity of injury) Works well for very low and very high
initial GCS scores. Age
Younger patients do better and those over 60 worse
Pupillary reactivity (severity of injury and ICP)
Hypotension Strongly predicts a poor outcome The only factor that can be changed
CT abnormalities predict a poor outcome (severity of injury and ICP)
Mortality from epidural hematoma about 10%.
Mortality from subdural hematoma 40 to 60%.
Hypoxia increases mortality.Hypotension doubles mortality.Recovery may continue for a year or
more.
Organize
In an emergency start with ABCs or ABCDEs.
Remember the GCS as top down and small number of options to large.
Think about the rest of your examination from the top down.
Think about brain injuries from the outside in.
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