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Case 1 - UCSF CME. Stiver 2013 0530 TBI.pdfTraumatic Brain Injury : Review, Update, and...
Transcript of Case 1 - UCSF CME. Stiver 2013 0530 TBI.pdfTraumatic Brain Injury : Review, Update, and...
5/30/2013
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Traumatic Brain Injury : Review, Update, and Controversies
Shirley I. Stiver MD, PhD
Case 1
32 year old male
• s/p high speed MVA • Difficult extrication • Intubated at scene
Case
• BP 75 systolic / palp
• GCS 3 (2T)
• Pupils 4 mm bilateral, reactive
• Motor – nil
• Open femur fracture
First Management Steps ?
A) Give Mannitol 0.5 g/kg iv bolus
B) GCS 3 - donor ?
C) Get stat CT scan
D) Elevate sys BP > 90 mmHg
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Intracranial Pressure (ICP)
ICP = Brain + CSF + Blood vascular volume + Mass Lesion
Pressure Volume Curve
Compliance ∆V/∆P
• Small increase in the intracranial volume
• significantly increase the ICP and ppt herniation
Low
High
Raised Intracranial Pressure
Cerebral Herniation
Indications for Mannitol
• Signs of impending cerebral herniation
(Level III)
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Motor
Motor Score
1 Nil
2 Decerebrate posturing
3 Decorticate posturing
4 Withdrawal
5 Localizes
6 Obeys commands
Treatment Raised ICP
Mannitol
• Osmotic diuresis
• Reduces blood viscosity
1-1.4gm/kg, bolus
Watch for hypotension
Glasgow Coma Scale
Motor component of the GCS is most predictive of outcome
GCS
Eyes 4
Verbal 5
Motor 6
Perform after resuscitation & before sedation or paralytics
Poor GCS check Brainstem reflexes
Importance of testing
• Pupils
• Corneals,
• Cough and gag
Before Paralytics
• Often determines whether to take patient to OR
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Differentiating primary versus secondary injury
• Early GCS in the field – gives you the closest assessment of the severity of the primary impact – Resuscitated evaluation ; …
hypoxia / hypotension – false positive
– No drugs / alcohol on board
• Importance of the reports from the emergency response team
• Importance of serial GCS & neurological testing
Guidelines Blood Pressure – Level II
Hypotension strong predictor of outcome
• Single episode sys BP<90 doubles mortality
• Avoid hypotension sys BP < 90 mmHg
• Isotonic saline
• Fluid resuscitation a balance:
Maintain cerebral perfusion ↔ avoid fluid overload, osmotic shifts, brain edema
Case Non –Contrast CT scan Next ?
A) OR for decompressive craniectomy
B) ICU observation
C) ICU and ICP monitoring
D) Ortho to OR femur repair
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Guideline for ICP Monitoring
GCS < 8
With Abnormal CT scan Unresponsive with
absence of a neurological exam that
can be followed
Normal CT scan with -age > 40 -unilateral or bilateral posturing -systolic pressure < 90 mmHg -ethanol intoxication
Guideline
ICP Treat for threshold > 20mmHg
ICP Monitoring
Tiers of Therapy
Tier 1 • EVD drainage ; Sedation (Mannitol x 1)
Tier 2 • Osmotic therapy; Mannitol or Hypertonic N/S ;
pCO2 30-35 mmHg; paralysis
Tier 3 • Decompressive craniectomy ;
• Induced Barbiturate or propofol coma
Cerebral Perfusion Management
CPP = Mean arterial blood pressure – ICP
CPP goal > 60 mmHg Lund Therapy
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Advanced Monitoring ?
• What advanced monitoring might best help you manage this patient ?
A) Cerebral blood flow probe
B) Brain tissue oxygen monitor
C) SjVO2 –jugular venous saturation
Brain Tissue Oxygen
• Brain O2 probes placed in white matter
• Normal values for white matter 20-30mmHg
Brain Tissue Oxygenation
• Cerebral blood flow •
• O2 content of blood • Dissociation
& Diffusion of O2
BBB
Normal values
(white matter)
20-30
mmHg
Critical values < 15
Jugular Venous Saturation
Global measure of cerebral metabolism:
Measures total venous brain tissue oxygen in jugular bulb
Oxygen extraction by the brain
SjvO2 Normal values 50-75%
Critical values < 50
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Case ICP 18
MAP 86
FiO2 50%
7.4/35/141
PBrO2 18
SjVO2 90
UpDATES
1. “A Trial of Intracranial-Pressure Monitoring in TBI” R. Chesnut et al. NEJM 367: 2471-81 (2012).
– Treatment based on ICP monitor vs Clinical Exam
2. Protect Study – Methylprednisolone
3. Pharmacologic DVT Prophylaxis in TBI
ICP versus Clinical Exam
324 severe TBI patients
• Randomly assigned to
1. ICP monitor group
2. Clinical group
– Outcome measures : survival, functional and neuropsychological outcome at 6 months
No randomized trial to show that treatment based on monitored ICP improves outcome
R. Chesnut NEJM 367: 2471-81 (2012)
ICP versus Clinical Results
At 6mo ICP Clinical p value
1° Outcome score
56 53 0.5
Mortality 39% 44% 0.4
Favorable Outcome
44% 39%
Unfavorable Outcome
17% 17%
Conclusions Management guided by ICP Monitoring NOT > Clinical Exam
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DVT Prophylaxis after TBI
The controversy :
• TBI : enoxaparin has the potential to iatrogenically exacerbate intracranial hemorrhage
• View that hemorrhage stabilizes with time
• Is there an early prohibitive period, but once hemorrhage stabilizes, anticoagulation is safe -- Timing ?
Recent Studies Pharmacologic DVT Prophylaxis in TBI
Importance of hemorrhage stability before starting prophylaxis
Worsening of hemorrhage between 1st and 2nd CT scan followed by enox 13-fold increase in rate of continued hemorrhage
Stable scan – no hemorrhage expansion
A. Levy et al, J. Trauma 68: 886-94 (2010)
Recent Studies Pharmacologic DVT Prophylaxis in TBI
• Risk stratification by injury patterns -different lesions have different risks of hemorrhage progression different time frames for stabilization, and different times for starting prophylaxis
Low risk for enox at 24h :
SDH < 9mm EDH < 9mm Contusion < 2cm Single contusion per lobe
S. Norwood J Trauma 65: 1021-27 (2008)
Parkland Model
Risk Stratification for Starting Enoxaparin
Low Risk
Repeat CT at 24h
Stable ?
Start Enox at 24 h
Moderate Risk
Repeat CT at 72 h Stable ?
Start Enox at 72 h
High Risk
Consider IVC filter
H. Phelan, J Neurotrauma 29: 1821-28 (2012)
yes yes
no no
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Controversy
Does Decompressive Craniectomy Improve Outcome ?
DECRA Study
Decra: Study Methods
• Severe TBI (GCS 3-8) with Diffuse injury
• Tier 1 therapy: osmotics, sedation, paralytics, EVD drainage
• Refractory ICP defined as >20mmHg for > 15min
Bifrontal decompressive craniectomy
Continued ICU Care
Tier 2 & 3 therapy :
• mild hypothermia to 35’
• Barbiturate coma
DECRA Study Results : GOSE @6mo
DC
0
5
10
15
20
25
Die Veg LS US LM UM LG UG
DC
MC
• DC shifted survivors from favorable unfavorable outcome (dependent for ADLs)
Hemi- Craniectomy
RescueICP • www.rescueicp.com
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Conclusions
Basic Principles – Once ICP already used up compensatory
reserves
– Mannitol for impending herniation
– Poor GCS brainstem exam
– Distinguish primary v secondary injury
– Hypoxia / hypotension / drugs & ethanol may mask GCS
– ICP monitoring for unresponsive without neuro exam
DECRA: Study Design
• 155 adults, aged 15-59 yrs
• Severe TBI (GCS 3-8) with Diffuse injury
• Randomized Standard Care vs Bifrontal craniectomy for Refractory ICP
• Outcome : GOS-E @ 6mo ‡
Exclusions - Dilated, unreactive pupils - Mass lesions (unless small) - Cardiac arrest at scene
History Pharmacologic DVT Prophylaxis in TBI
History • No role for pharmacologic prophylaxis in TBI before
2000
• Gearhart 2000 – – DVT prophylaxis in 102 trauma patients
– 26 TBI with intracranial blood no instance of TBI worsening
• Kim 2002 - – 76 severe TBI, unfrac heparin; groups <72 h and > 72 h ;
– no increase in intracranial bleeding between groups
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Decra: Study Methods
• Severe TBI (GCS 3-8) with Diffuse injury
• Tier 1 therapy: osmotics, sedation, paralytics, EVD drainage
• Refractory ICP defined as >20mmHg for > 15min
Bifrontal decompressive craniectomy
Continued ICU Care
Tier 2 & 3 therapy :
• mild hypothermia to 35’
• Barbiturate coma
Life saving DC >72 h after admission
DECRA: Study Results
• Icp control