Case 1 Traumatic Brain Injury : Review, Update, and Controversies - PDF document

5/30/2013 Case 1 Traumatic Brain Injury : Review, Update, and Controversies 32 year old male • s/p high speed MVA Shirley I. Stiver MD, PhD • Difficult extrication • Intubated at scene Case • BP 75 systolic / palp • GCS 3 (2T) • Pupils 4 mm bilateral, reactive First Management Steps ? • Motor – nil A) Give Mannitol 0.5 g/kg iv • Open femur fracture bolus B) GCS 3 - donor ? C) Get stat CT scan D) Elevate sys BP > 90 mmHg 1

5/30/2013 Compliance ∆V/∆P Intracranial Pressure (ICP) Pressure Volume Curve • Small increase in the intracranial volume •  significantly increase the ICP Low and ppt herniation ICP = Brain + CSF + Blood vascular volume + Mass Lesion High Raised Intracranial Pressure Indications for Mannitol Cerebral Herniation • Signs of impending cerebral herniation (Level III) 2

5/30/2013 Motor Treatment Raised ICP Motor 1-1.4gm/kg, bolus Score 1 Nil Mannitol 2 Decerebrate • Osmotic diuresis posturing • Reduces blood 3 Decorticate posturing viscosity 4 Withdrawal 5 Localizes 6 Obeys commands Watch for hypotension Poor GCS  check Brainstem reflexes Glasgow Coma Scale GCS Eyes 4 Perform after resuscitation Importance of testing & before sedation or • Pupils Verbal 5 paralytics • Corneals, • Cough and gag Motor 6 Before Paralytics Motor component of the GCS is most predictive of outcome • Often determines whether to take patient to OR 3

5/30/2013 Differentiating primary versus Guidelines Blood Pressure – Level II secondary injury • Early GCS in the field – gives you • Avoid hypotension sys the closest assessment of the BP < 90 mmHg severity of the primary impact – R esuscitated evaluation ; … • Isotonic saline hypoxia / hypotension – false • Fluid resuscitation a positive balance : – No drugs / alcohol on board  Maintain cerebral • Importance of the reports from perfusion ↔ avoid fluid the emergency response team Hypotension strong predictor of overload, osmotic shifts, outcome • Importance of serial GCS & brain edema • Single episode neurological testing sys BP<90 doubles mortality 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 4

5/30/2013 ICP Monitoring Guideline for ICP Monitoring GCS < 8 With Abnormal CT scan Unresponsive with absence of a neurological exam that can be followed Guideline ICP Treat for threshold > 20mmHg Normal CT scan with -age > 40 -unilateral or bilateral posturing -systolic pressure < 90 mmHg - ethanol intoxication Cerebral Perfusion Management Tiers of Therapy CPP = Mean arterial blood pressure – ICP Tier 1 • EVD drainage ; Sedation (Mannitol x 1) Tier 2 CPP goal > 60 mmHg • Osmotic therapy; Mannitol or Hypertonic N/S ; pCO 2 30-35 mmHg; paralysis Lund Therapy Tier 3 • Decompressive craniectomy ; • Induced Barbiturate or propofol coma 5

5/30/2013 Brain Tissue Oxygen Advanced Monitoring ? • What advanced monitoring might best help you manage this patient ? A) Cerebral blood flow probe B) Brain tissue oxygen • Brain O2 probes placed in monitor white matter C) SjVO2 – jugular venous saturation • Normal values for white matter 20-30mmHg Brain Tissue Oxygenation Jugular Venous Saturation • Cerebral blood flow Global measure of • cerebral metabolism: BBB Measures total venous brain tissue oxygen in jugular bulb • O2 content of blood  Oxygen extraction Dissociation • by the brain & Diffusion of O2 Normal values 20-30 SjvO2 Normal values 50-75% mmHg (white matter) Critical values < 50 Critical values < 15 6

5/30/2013 UpDATES Case ICP 18 1. “A Trial of Intracranial -Pressure Monitoring in MAP 86 TBI” R. Chesnut et al. NEJM 367: 2471-81 (2012). – Treatment based on ICP monitor vs Clinical Exam FiO2 50% 7.4/35/141 PBrO2 18 2. Protect Study – Methylprednisolone 3. Pharmacologic DVT Prophylaxis in TBI SjVO2 90 At 6mo ICP Clinical p ICP versus Clinical Exam value ICP versus Clinical 1° Outcome 56 53 0.5 Results score No randomized trial to show that treatment based on Mortality 39% 44% 0.4 monitored ICP improves outcome Favorable 44% 39% 324 severe TBI patients Outcome • Randomly assigned to Unfavorable 17% 17% 1. ICP monitor group Outcome 2. Clinical group Conclusions – Outcome measures : survival, functional and Management guided by neuropsychological outcome at 6 months ICP Monitoring NOT > Clinical Exam R. Chesnut NEJM 367: 2471-81 (2012) 7

5/30/2013 Recent Studies Pharmacologic DVT DVT Prophylaxis after TBI Prophylaxis in TBI The controversy : • TBI : enoxaparin has the potential to Importance of hemorrhage stability before starting prophylaxis iatrogenically exacerbate intracranial hemorrhage  Worsening of hemorrhage between 1 st and 2 nd CT scan followed by enox  13-fold increase in • View that hemorrhage stabilizes with time rate of continued hemorrhage • Is there an early prohibitive period, but once  Stable scan – no hemorrhage expansion hemorrhage stabilizes, anticoagulation is safe - - Timing ? A. Levy et al, J. Trauma 68: 886-94 (2010) Recent Studies Pharmacologic DVT Parkland Risk Stratification for Model Prophylaxis in TBI Starting Enoxaparin • Risk stratification by injury patterns Moderate Low Risk High Risk -different lesions have different risks of hemorrhage Risk progression  different time frames for stabilization, and  different times for starting prophylaxis Repeat CT Repeat CT no no Consider at 24h at 72 h IVC filter Stable ? Stable ? Low risk for enox at 24h : yes yes  SDH < 9mm Start Enox Start Enox  EDH < 9mm at 24 h at 72 h  Contusion < 2cm  Single contusion per lobe S. Norwood J Trauma 65: 1021-27 (2008) H. Phelan, J Neurotrauma 29: 1821-28 (2012) 8

5/30/2013 Controversy Decra: Study Methods Does Decompressive Craniectomy Improve Outcome ? • Severe TBI (GCS 3-8) with Diffuse injury • Tier 1 therapy: osmotics, sedation, paralytics, EVD DECRA Study drainage • Refractory ICP defined as >20mmHg for > 15min Bifrontal decompressive Continued ICU Care craniectomy Tier 2 & 3 therapy : • mild hypothermia to 35’ • Barbiturate coma Hemi- DECRA Study Results : GOSE @6mo Craniectomy 25 20 15 RescueICP 10 DC • www.rescueicp.com MC 5 0 Die Veg LS DC US LM UM LG UG • DC shifted survivors from favorable  unfavorable outcome (dependent for ADLs) 9

5/30/2013 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 History Pharmacologic DVT Prophylaxis DECRA: Study Design in TBI • 155 adults, aged 15-59 yrs History • Severe TBI (GCS 3-8) with Diffuse injury • No role for pharmacologic prophylaxis in TBI before 2000 • Randomized Standard Care vs Bifrontal • Gearhart 2000 – craniectomy for Refractory ICP – DVT prophylaxis in 102 trauma patients • Outcome : GOS- E @ 6mo ‡ – 26 TBI with intracranial blood  no instance of TBI worsening • Kim 2002 - Exclusions – 76 severe TBI, unfrac heparin; groups <72 h and > 72 h ; – no increase in intracranial bleeding between groups - Dilated, unreactive pupils - Mass lesions (unless small) - Cardiac arrest at scene 10

5/30/2013 Decra: Study Methods DECRA: Study Results • Severe TBI (GCS 3-8) with Diffuse injury • Icp control • Tier 1 therapy: osmotics, sedation, paralytics, EVD drainage • Refractory ICP defined as >20mmHg for > 15min Bifrontal decompressive Continued ICU Care Tier 2 & 3 therapy : craniectomy • mild hypothermia to 35’ • Barbiturate coma Life saving DC >72 h after admission 11