Mechanisms of Injury Traumatic Brain Injury Blunt(Closed)PenetratingExplosion Fall GSW Stab Blast FragmentMotor vehicle crashes (MVC)
Relative Proportion of Levels of Care for TBISource: CDC: Traumatic Brain Injury in the United States, October 2004
50,000 Deaths235,000Hospitalizations1,111,000Emergency Department Visits???Other Medical Care or No Care
Blast Wave PhysicsCourtesy of Keith Prusaczyk, Ph.D.
Types of InjuriesPrimary Injuries Scalp lacerationsSkull fractures (Linear, depressed, basiliar)Facial fractures (Le Forte 1 3)Concussion (mild traumatic brain injury): amnesiaCerebral contusionAxial / Extra-axial haematomasDiffuse axonal injury
ConcussionThe diagnostic sign is amnesiaTakes few months to resolveNo morphological abnormalityNo abnormalities on radiologyBeware of Second Impact Syndrome
Cerebral ContusionsFrontal & Temporal regions commonlyCan be multiple and bilateral An area of haemorrhage & oedemaDiagnose by CT / MRIIt is primary injury but produces secondary injury due to increased ICP
Diffuse Axonal InjuryRotational ForcesAcceleration Deceleration injuriesNeuronal tearing in white matterSeen on MRISuspect if many cerebral contusions on CT scan and patient has prolonged coma (>6hrs) with no evidence of a SOL.
Secondary InjuryCellular changesHypoxiaHypercarbiaHypotensionCerebral oedemaVasogenicCytotoxicIncreased Intra Cranial Pressure
Why Worry?Increasing ICPDecreased cerebral perfusion pressure causing ischaemiaMidline shift causing ventricular obstructionHerniationUncalCentralCingulate (subfalcine)Cerebellar Transcalvarial
HerniationUncal HerniationMedial temporal lobe (Uncus) compresses midbrain with increasing ICPPressure in the region of kernohans notch causes ipsilateral pupillary dilatation, ipsi / contralateral hemiparesis and possible posterior cerebral artery compressionDecreased level of consciousnessRespiratory pattern changeGoal is to prevent this from occuring
Recognition and Management of Specific Head InjuriesSkull FractureCause of Injury Most common cause is blunt trauma Signs of InjurySevere headache and nauseaPalpation may reveal defect in skullMay be blood in the middle ear, ear canal, nose, ecchymosis around the eyes (raccoon eyes) or behind the ear (Battles sign)Cerebrospinal fluid may also appear in ear and noseCareImmediate hospitalization and referral to neurosurgeon
Recognition and Management of Specific Eye Injuries
Mechanisms of Injury3 CollisionsCar hits objectHead hits windshieldBrain hits inside of skull
Mechanisms of Injury
Mechanisms of InjuryBrain movement inside the skullBase of skull is very roughMost brain movement is at the topBrain suspended by vessels and brain tissue that can be torn by movement, especially at the base
Mechanism of Injuries, cont.Rotational injuries injury occurs acceleration-deceleration of the brain does not follow straight linear path.Brain twists and moves at angles causing stretching and shearing of brain tissue and potential vascular injury.Penetrating include missile injuries, GSW or impalement.
Response to InjuryDue to increased blood volume (not edema)Natural response to injury anywhere on your bodyBody rushes nutrients to heal injured area
Response to InjuryIncrease in cerebral edema (water) develops after 24-48 hours and peaks in 3-5 daysNot an acute concern, per say
Intracranial PressureThe pressure of the brain contents within the skull is intracranial pressure (ICP)The pressure of the blood flowing through the brain is referred to as the cerebral perfusion pressure (CPP)The pressure of the blood in the body is the mean arterial pressure (MAP)
Intracranial PressureMAP (Mean Arterial Pressure) can be determined by a simple formula:
MAP = systolic + 2x diastolic 3
Intracranial PressureExample of MAP
B/P is 120/80
MAP = 120 + 160 = 280 = 93 mm/hg 3 3
Intracranial PressureIntracranial pressure (ICP)is measured by a device that is implanted through the skull by a surgeon
The normal value for ICP is 0 - 10 mm/hg
Intracranial PressureCerebral Perfusion Pressure (CPP) can be determined by the following formula:CPP = MAP - ICP
Normal CPP range is 60 - 150 for autoregulation to work well!
Intracranial PressureExample of CPPBlood Pressure is 140/80ICP is 30CPP = 100 - 30 = 70 mm/hgIs this enough for autoregulation?What would happen if the ICP was 80?
Assessment FindingsCushings Triadhypertensionbradycardiaaltered respirationsLATE SIGN!
Why do we get into Cushings Triad?
Assessment FindingsBP of 250/130MAP would be 170!Why is the MAP so high?The ICP is 100!Is this a good thing?Should we lower the blood pressure?
Concussions (Mild Head Injuries)Characterized by immediate and transient post-traumatic impairment of neural functionCause of InjuryResult of direct blow, acceleration/deceleration forces producing shaking of the brainCoup mechanismContra-coup mechanismSigns of InjuryBrief periods of diminished consciousness or unconsciousness that lasts seconds or minutesHeadache, tinnitus, nausea, irritability, confusion, disorientation, dizziness, posttraumatic amnesia, retrograde amnesia, concentration difficulty, blurred vision, photophobia, sleep disturbances
CareThe decision to return an athlete to competition following a brain injury is a difficult one that takes a great deal of considerationIf any loss of consciousness occurs the ATC must remove the athlete from competition With any loss of consciousness (LOC) a cervical spine injury should be assumedObjective measures (BESS and SAC) should be used to determine readiness to playA number of guidelines have been established in an effort to aid clinicians in their decisions
Scalp InjuriesCause of InjuryBlunt trauma or penetrating trauma tends to be the causeCan occur in conjunction with serious head traumaSigns of Injury Athlete complains of blow to the headBleeding is often extensive (difficult to pinpoint exact site)CareClean w/ antiseptic soap and water (remove debris)Cut away hair if necessary to expose areaApply firm pressure or astringent to reduce bleedingWounds larger than 1/2 inch in length should be referredSmaller wounds can be covered w/ protective covering and gauze (use extra adherent)
Facial LacerationsCause of InjuryResult of a direct impact, and indirect compressive force or contact w/ a sharp objectSigns of InjuryPainSubstantial bleeding CareApply pressure to control bleedingReferral to a physician will be necessary for stitches
CareControl bleeding and refer to a physician for X-ray,examination and reductionUncomplicated and simple fractures will pose little problem for the athletes quick returnSplinting may be necessary
Recognition and Management of Specific Ear Injuries
Rupture of the Tympanic MembraneCause of InjuryFall or slap to the unprotected ear or sudden underwater variation can result in a ruptureSigns of InjuryComplaint of loud pop, followed by pain in ear, nausea, vomiting, and dizzinessHearing loss, visible rupture (seen through otoscope)CareSmall to moderate perforations usually heal spontaneously in 1-2 weeksInfection can occur and must be continually monitoredShould not fly until condition is resolved
Rupture Tympanic Membrane
Recognition and Management of Specific Eye InjuriesOrbital Hematoma (Black Eye)Cause of Injury Blow to the area surrounding the eye Signs of InjurySigns of a more serious condition may be displayed as a subconjunctival hemorrhageSwelling and discolorationCareCold application for at least 30 minutes, 24 hours of rest if athlete has distorted visionDo not blow nose after acute eye injury may increase hemorrhaging
Orbital Fracture Cause of Injury Direct trauma to the eyeball Signs of InjuryBlurred visionDiplopiaRestricted eye movementDownward displacement of the eyeSoft-tissue swelling and hemorrhagingNumbness Infraorbital nerve entrapmentCareX-ray will be necessary to confirm fractureAntibiotics Decrease risk of infection (due to proximity of maxillary sinus and bacteria)Treat surgically or allow to resolve spontaneously
Critical Care Management in Traumatic Brain Injury Dr.(Mrs.) Bibhukalyani DasProf. & HOD Neuroanaesthesiology, Neuro ICU & Pain ClinicBangur Institute of Neuroscience & Psychiatry Kolkata
TBI is a global public health problem.Urbanization : Vehicles Incidence in Developing Countries. 70% victims of RTA sustain TBI 70% of RTA deaths are due to TBIMajority death occur in 72 hrs.Victims :Young males in productive age groupChildren constitute 25-30% of all TBI victimsLoss of life, Rehab of disabledSig.Econo.burdn
Pathophysiology:TBIA.Primary Injury (Br. damage @ impact) Minor Concussion DAI BS dysf. Followed by series of secondary events : (i) Focal hematoma / contusion (ii)Changes in CBF & CMRO2 (iii) ICP (iv) Biochemical changes @ Cellular level B.Secondary Brain Injury (hours to days)
TBI : Clinical Grading Duration of Unconsciousness & GCSMild : < 30 minutes 13-15Moderate: > 30 min. < 6 hours 9-12Severe : > 6 hours