head injury management edited

8/8/2019 Head Injury Management Edited

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Head injury managementHead injury management

Adapted from source Adapted from source



Traumatic Brain InjuryTraumatic Brain Injury

22,00022,000--25,000/yr pts Australian25,000/yr pts Australian

± ± 1,493 moderately TBI1,493 moderately TBI

± ± 1,000 severe cases of T

BI1,000 severe cases of T

BI ± ±

Qld incidence 200/100,000Qld incidence 200/100,000

National 140/100,000National 140/100,000

1/3 trauma deaths1/3 trauma deaths



Assessment History Assessment History

HistoryHistory Time & Mechanism InjuryTime & Mechanism Injury

Neuro statusNeuro status ± ± at scene (at scene (GCS Score and pupils)GCS Score and pupils)

± ± inin transporttransport ± ± After resuscitation After resuscitation

Vital signsVital signs Hypoxia and hypotensionHypoxia and hypotension

Time of intubation presence of apnoeaTime of intubation presence of apnoea

Associated injuries Associated injuries

Age Age

Alcohol / drugs/s intake Alcohol / drugs/s intakeBrain CTBrain CT




1515--1313 MildMild

99 ± ± 12 Moderate12 Moderate

<9<9 SevereSevere



Traumatic Brain InjuryTraumatic Brain Injury--GCSGCS

Eye openingEye opening ± ± SpontaneousSpontaneous 44

± ± To speechTo speech 33

± ± To painTo pain 22

± ± NONENONE 11

Verbal ResponseVerbal Response ± ± OrientatedOrientated 55

± ± Confused conversationConfused conversation 44

± ± Inappropriate wordsInappropriate words 33 ± ± IncomprehensibleIncomprehensible

soundssounds 22

± ± NoneNone 11

Best Motor Best Motor ResponseResponse ± ± ObeysObeys 66

± ± LocalisesLocalises 55

± ± WithdrawsWithdraws 44 ± ± Abnormal flexionAbnormal flexion 33

± ± Extensor responseExtensor response 22

± ± NoneNone 11

± ± After After ResuscitationResuscitation



Traumatic Brain InjuryTraumatic Brain Injury--GCSGCS

OutcomeOutcome

GCS 8GCS 8--15 = 0.3% mortality15 = 0.3% mortality

GCS 6GCS 6--77 = 24% mortality= 24% mortality

GCS 4GCS 4--55 = 49% mortality= 49% mortality

GCS 3GCS 3 = 83% mortality= 83% mortality

Klauber Klauber et al et al 1134 patients1134 patients



Pathophysiology TBIPathophysiology TBI

Primary insultPrimary insult

± ± Primary injuryPrimary injury ± ± Secondary injurySecondary injury

Secondary insultSecondary insult





± ± Primary injuryPrimary injury

± ± Direct damageDirect damage

involves mechanicalinvolves mechanical

forcesforces

Brain : contact energyBrain : contact energy

transfer and inertiatransfer and inertiaenergy transfer energy transfer

Vasculature: vesselVasculature: vessel

shear and disruptionshear and disruption



Secondary Brain injurySecondary Brain injury

Ischaemia (CBF)Ischaemia (CBF)

ExcitotoxicityExcitotoxicity

(CMRO2)(CMRO2)

Neuronal deathNeuronal death

cascades.cascades.

CerebralCerebral oedemaoedema

(vasogenic,(vasogenic,

cytotoxic).cytotoxic).

Inflammation.Inflammation.



Secondary insultsSecondary insults

Independently of the primary impactIndependently of the primary impact

Secondary insultsSecondary insults

Discrete processes, often iatrogenicDiscrete processes, often iatrogenic



Secondary injurySecondary injury



Traumatic brain injury managementTraumatic brain injury management

Primary injuryPrimary injury ± ± PreventionPrevention

Secondary injurySecondary injury ± ± attenuate secondary injury mechanismsattenuate secondary injury mechanisms

± ± manage raised ICPmanage raised ICP

Secondary insultSecondary insult ± ± Prevent and treat secondary insultsPrevent and treat secondary insults

± ± ABCD ABCD



Management Principles Secondary TBIManagement Principles Secondary TBI

Prevent further cerebral insultsPrevent further cerebral insultsHypoxiaHypoxia

HypotensionHypotension

HyperglycaemiaHyperglycaemiaDefend cerebral perfusionDefend cerebral perfusion

Limit intracranial pressure riseLimit intracranial pressure riseCerebral oedemaCerebral oedema

Cerebral blood volumeCerebral blood volumeCSF volumeCSF volume

Limit cerebral metabolic demandLimit cerebral metabolic demand



HypoxiaHypoxia ± ±Traumatic Brain InjuryTraumatic Brain Injury

Apnoea accompanies most head injuries. Apnoea accompanies most head injuries.

± ± Airway obstruction and aspiration major Airway obstruction and aspiration major

causes of death treatable head injuriescauses of death treatable head injuries

Hypoxia is commonHypoxia is common ± ± PaO2 60 mm Hg 46% admissions to the emergency departmentPaO2 60 mm Hg 46% admissions to the emergency department



Cerebral metabolic rate for oxygenCerebral metabolic rate for oxygen

(CMRO2)(CMRO2)

CMRO2CMRO2

± ± 3.5 ml/100g/min3.5 ml/100g/min

± ± 50 ml/min (20% of 50 ml/min (20% of

total basaltotal basalrequirements).requirements).

PaO2 minimal effectPaO2 minimal effect

on CBF until 50on CBF until 50mmHgmmHg



HypoxiaHypoxia ± ±Traumatic Brain InjuryTraumatic Brain Injury

Associated Associated

± ± 50% mortality rate50% mortality rate

± ± 50% severe disability50% severe disability

among survivorsamong survivors

Worse outcomes for Worse outcomes for

patients with TBI whopatients with TBI who

were intubated in thewere intubated in the

fieldfield

Why ?Why ?



IntubationIntubation ± ±TBITBI

Risk ICP, aspiration, and hypoxia.Risk ICP, aspiration, and hypoxia.

IPPV increases intra thoracic pressure,IPPV increases intra thoracic pressure, ± ± decrease venous return impair CPP.decrease venous return impair CPP.

Sedative agents can cause hypotensionSedative agents can cause hypotension

Risk of hyperventilationRisk of hyperventilation



Brain Trauma FoundationBrain Trauma Foundation

Prehospital guidelines recommendPrehospital guidelines recommend

intubationintubation

GCS scores 8GCS scores 8

Inadequate airwayInadequate airway

SaO2 < 90% with supplemental O2SaO2 < 90% with supplemental O2



PaCO2 TBIPaCO2 TBI

PaCO2 levels emergency departmentPaCO2 levels emergency department

± ± 17%, PCO2 < 3017%, PCO2 < 30

± ± 47%, PCO2 3047%, PCO2 30± ±3939

± ± 26%, PCO2 > 4026%, PCO2 > 40

Target PaCO2 range of 30Target PaCO2 range of 30± ±3939

± ± mortality 21%mortality 21%PaCO2 < 30 or >39PaCO2 < 30 or >39

± ± mortality 34%mortality 34%



PaCO2 CBFPaCO2 CBF

CO2 potent cerebralCO2 potent cerebralvasodilator vasodilator

1 mm Hg drop in1 mm Hg drop inPCO2 3% decreasePCO2 3% decreasein CBFin CBF

Hyperventilation canHyperventilation canlead to cerebrallead to cerebralischemiaischemia



Hypotension TBIHypotension TBI

Hypotension is common.Hypotension is common.

± ± 88± ±13% severe head injury pt.13% severe head injury pt.

Single episode of hypotension (SBP< 90Single episode of hypotension (SBP< 90

mm Hg) X2 mortality ratemm Hg) X2 mortality rate



Hypotension TBIHypotension TBI

HypotensionHypotension diff in adults to childrendiff in adults to children

Other injuryOther injurySpinal cord injurySpinal cord injury

Cardiac contusion/tamponadeCardiac contusion/tamponade

Tension pneumothoraxTension pneumothorax

Children may be hypotensive due to blood lossesChildren may be hypotensive due to blood lossesof head injuryof head injury



Pressure autoregulationPressure autoregulation

In normal brain CBFIn normal brain CBF

constant between MAP 50constant between MAP 50

mmHg and 150 mmHgmmHg and 150 mmHg

Nml CBFNml CBF

± ± 50ml/100g/min50ml/100g/min

± ± 700 ml/min700 ml/min

± ± 14 % of the cardiac output.14 % of the cardiac output.

Severe TBI CBF is bloodSevere TBI CBF is blood

pressure dependent.pressure dependent.



CBF TBICBF TBI

Severe TBI CBF is blood pressure dependent.Severe TBI CBF is blood pressure dependent.

Cerebral perfusion pressure (CPP)Cerebral perfusion pressure (CPP)

± ± CPP = MAP CPP = MAP ± ± ICPICP (or CVP, whichever is the highest)(or CVP, whichever is the highest)

Increase in mortality and poor outcome whenIncrease in mortality and poor outcome whenCPP < 70 mmHg for a sustained period.CPP < 70 mmHg for a sustained period.



Pressure autoPressure auto--regulationregulation

MAP MAP

1/3 (SBP1/3 (SBP--DBP) +DBPDBP) +DBP

CPP = MAP CPP = MAP ± ± ICPICP

ICP is 7ICP is 7--17 mmHg17 mmHg



Defend cerebral perfusionDefend cerebral perfusion

MABPMABP 90 mmHg90 mmHgCPP = MABP CPP = MABP ± ± (ICP or JVP)(ICP or JVP)

Avoid raised JVP or CVP Avoid raised JVP or CVP

± ± Blood volumeBlood volume

± ± JVP obstructionJVP obstruction

± ± Raised intrathoracic pressureRaised intrathoracic pressure

± ± Excessive PEEPExcessive PEEP

Inotropes NAdr or Adr Inotropes NAdr or Adr

PositionPosition

± ± Nurse head up 20Nurse head up 20--3030°°(if spine cleared)(if spine cleared)

± ± CC--spine collar spine collar

Avoid excessive ventilatory pressures Avoid excessive ventilatory pressures



PressurePressure--Volume CurveVolume Curve

Compensation

Point of n Decompensation

Herniation

Volume of Mass

ICP

(mm Hg)

5-

10-

15-

20-25-

30-35-

40-

45-50-

55-

60-



0 20 40 60 80 100 120

1

2

Intracranial tissue volume

Normal

Head injury

Brain

swelling

qCSF volume

Haematoma



Limit intracranial pressure riseLimit intracranial pressure rise

Cerebral blood volumeCerebral blood volume

Avoid Avoid hypertensionhypertension

± ± CVS responses to pain, stimulationCVS responses to pain, stimulation

± ± Analgesia & sedation associated injuries Analgesia & sedation associated injuriesTransfersTransfers

Procedures IntubationProcedures Intubation

Control PaCO2Control PaCO2 ± ± Ventilation to PaCOVentilation to PaCO22 = 34= 34 -- 36 mmHg36 mmHg



Limit intracranial pressure riseLimit intracranial pressure rise

Cerebral oedemaCerebral oedema

± ± Avoid hypo Na+ Avoid hypo Na+ ± ± Target Na+ >135 mmolTarget Na+ >135 mmol

0.9% saline0.9% saline



Signs of Impending HerniationSigns of Impending Herniation

Deteriorating LOC (GCS score)Deteriorating LOC (GCS score)

Pupillary asymmetry >1mmPupillary asymmetry >1mm

Motor asymmetryMotor asymmetry

Extensor (decerebrate) posturing (M2),Extensor (decerebrate) posturing (M2),

Cushing¶s response BP HRCushing¶s response BP HR

Respiratory arrestRespiratory arrest



Urgent measures to lower critical ICPUrgent measures to lower critical ICP

Mannitol AdministrationMannitol Administration

Hypertonic SalineHypertonic Saline



HyperventilationHyperventilation--ICPICP

Hyperventilation TherapyHyperventilation Therapy

PaCO2 < 25 mmHg noPaCO2 < 25 mmHg no

further reduction in CBFfurther reduction in CBF

HypoCO2HypoCO2

± ± shift the oxygenshift the oxygen

dissociation curve to leftdissociation curve to left

± ± oxygen less available tooxygen less available to

the tissues.the tissues.



Herniating patientsHerniating patients ± ± goal of PaCO2 30goal of PaCO2 30± ±35 mm Hg35 mm Hg

EndEnd--tidal PCO2 not reliable measure of PaCO2tidal PCO2 not reliable measure of PaCO2

Without cerebral herniationWithout cerebral herniation ± ± PaCO2 goal of 35PaCO2 goal of 35 -- 40 mm Hg40 mm Hg

± ± Vt 10 ml/kg and 10 bpmVt 10 ml/kg and 10 bpm

± ± Prophylactic hyperventilation worse prognosisProphylactic hyperventilation worse prognosis

HyperventilationHyperventilation--ICPICP



Hypothermia critical ICPHypothermia critical ICP

Admission temp (<35C) is a predictor of death in trauma Admission temp (<35C) is a predictor of death in traumapatientspatients

Hypothermia TBI controversialHypothermia TBI controversial

Induced therapeutic hypothermia vs accidentalInduced therapeutic hypothermia vs accidentalhypothermiahypothermia

66± ±7% decrease CMRO2 / 1C7% decrease CMRO2 / 1C decrease in tempdecrease in temp

RewarmingRewarming



TBI Management MinimiseTBI Management Minimise CMROCMRO22

SedationSedation ± ± no evidence regarding superiority of any particular sedativeno evidence regarding superiority of any particular sedative

use short acting agentsuse short acting agents

?role NMB?role NMB

Control temperatureControl temperature ± ± Brain in TBI temp 2 C degrees > core tempBrain in TBI temp 2 C degrees > core temp

± ± Mild hypothermia 34Mild hypothermia 34--35.5C35.5C

Prevent/treat seizuresPrevent/treat seizures ± ± minimize CMROminimize CMRO22

± ± Phenytoin (loading dose 15mg/kg, infuse 50mg/min)Phenytoin (loading dose 15mg/kg, infuse 50mg/min)



Trauma response TBITrauma response TBI

TBI with onTBI with on--scenescenestabilization in the fieldstabilization in the field ± ± better survival ratesbetter survival rates

± ± longlong--term outcomes incur term outcomes incur

longer medianlonger median

Independent of sceneIndependent of scenetimetime ± ± (113 vs 45 minutes,(113 vs 45 minutes,

respectively; p < 0.001)respectively; p < 0.001)

± ± Compared with other Compared with other traumatrauma




Neurosurgical expertiseNeurosurgical expertisesingle most importantsingle most importantdeterminant of outcome in ptsdeterminant of outcome in ptswith mass lesionswith mass lesions

Acute subdural hematomas Acute subdural hematomas

mortality ratemortality rate

30% if evacuation < 4hrs30% if evacuation < 4hrs90% if surgical evacuation > 490% if surgical evacuation > 4hrs.hrs.




Intervention of air Intervention of air medical and rapidmedical and rapid--response teamsresponse teams

Pts with minimalPts with minimalneurological functionsneurological functions(GCS 4)(GCS 4)

Greatest increase inGreatest increase insurvival.survival.



Maintain mean BP > 90 mm Hg

MaintainP

aCO2 approximately 35mm Hg

Use isotonic solution for euvolemia

Frequent neurologic examsReassess ABC if deterioration

Things to Do:



Things to Avoid:

Do Not Allow patient to become

hypotensive Do Not Allow patient to become hypoxic

Do Not hyperventilate

Do Not Use hypotonic IV fluids Do Not Paralyse before performing

complete exam (if possible )



PrognosisPrognosis

Very difficult to accurately predict prognosisVery difficult to accurately predict prognosiswithin the first 24 hrs of TBIwithin the first 24 hrs of TBI

Avoid assessments of medical futility and Avoid assessments of medical futility andpossible organ donationpossible organ donation

Allow the results of resuscitative efforts to be Allow the results of resuscitative efforts to beevaluatedevaluated



?S?S



Secondary injurySecondary injury

head injury management edited

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