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Traumatic Brain Injuries. Dr. Arif Baradia M. Med (Ortho) Supervisor: Professor Mwangombe. What is Traumatic Brain Injury?. PROCESS not EVENT PRIMARY and SECONDARY BRAIN INJURY Penetrating or Non-penetrating. Epidemiology. 1.5 m per year MVA 45% Falls 30%
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Traumatic Brain Injuries Dr. ArifBaradiaM. Med (Ortho) Supervisor: Professor Mwangombe
PROCESS not EVENT • PRIMARY and SECONDARY BRAIN INJURY • Penetrating or Non-penetrating
Epidemiology • 1.5 m per year MVA 45% Falls 30% Occupational 10% Recreational 10% Assault 5% Role of Alcohol
Epidemiology • 40-60% of head injured patients have extremity injury • 32,000-48,000 head injury survivors with orthopaedic injuries annually
Pathophysiology of Head Injury • Monroe - Kellie doctrine CSF 10% BLOOD 10% BRAIN 80% Rigid “Box” Aka The Skull
Cerebral Blood Flow • 15% C.O • 750ml/min • CPP = MAP – ICP maintain above 70 mmHg
Mechanisms of Brain Injury • Brain Contusion • Raised ICP • Diffuse Axonal Injury • Stroke
1.Brain Contusion • cell death + hemorrhage • The contusion often occurs at a site distant from the point of impact
Raised ICP Brain Oedema/Swelling Extra-dural Hematoma Sub-Dural Hematoma
Secondary Brain Injury Excitatory Neurotransmitters Calcium/Sodium Influx Phospholipases Proteases Arachidonic Acid + water = cytotoxic edema Prostaglandins Thromboxanes Leukotrienes Cell mb integrity Cell function Cell viability
Overview • Initial evaluation • Prognosis • Management of Head Injury • Orthopaedic Issues • Operative vs. nonoperative treatment • Timing of surgery • methods • Fracture healing in head injury • Associated injuries • Complications
Initial Evaluation Pre-Hospital care Emergency Department ATLS protocol Primary Survey Secondary survey History Physical Exam – GCS < 9, 9 – 12, > 13, xT, xTP Imaging
ABCDE • GCS < 9 – intubate • Hyperventilation, 100% Oxy sat • BP > 90mmHg • Pupils • GCS • ICP monitoring
Hyperosmolar therapy • Mannitol0.25 – 1 g/kg infusion • Hypertonic saline • Albumin HCT 30 – 33% PaCO2 – 35 +/- 2 mmHg CVP 8 – 14 mmHg Avoid dextrose IV Maintain euthermia or hypothermia
Role of Orthopedic Surgeon • Resuscitation • Treatment Methods/Timing • Associated injuries • Complications
1. Damage Control Surgery Goal • Limit ongoing hemorrhage, hypotension, and release of inflammatory factors • Limit stress on injured brain • Initial surgery • <1-2 hrs • limit surgical blood loss
Methods • Initial focus on stabilization • External fixation • Limited debridement • Limited or no internal fixation or definitive care • Delayed definitive fixation (5-7 days)
2. Resuscitation: Role of Orthopaedics • Goal: limit ongoing hemorrhage and hypotension • pelvic ring injury-- external fixation reduced mortality from 43% to 7% (Reimer, J Trauma, ‘93) • open injury--limit bleeding • long bone fracture--controversial
Long Bone Fracture in the Head Injured Patient • Early fixation (<24 hours) well accepted in the polytrauma patient • In the head injured patient early fixation may be associated with • hypotension – elevated ICP • blood loss/coagulopathy • Hypoxia • Fat embolism • Advocates of early and delayed treatment
Early Osteosynthesis Hofman ‘91, Poole ’92, McKee ’97 – either no difference or lower mortality and GOS Bone ‘94, Starr ‘98 – delayed fixation worse mortality and 45X pulm complications
Delayed Osteosynthesis • Reynolds ’95, Jaicks ’97, Townsend ‘98 – more hypotension i.e. more fluid resusc needed, lower discharge GCS
Fracture Care Decided on a case by case basis but surgery is often optimal • Alignment • Articular congruity • Early rehabilitation • Facilitated nursing care Non-operative fracture care
BUT Minimise • Hypotension • Hypoxia • Elevated ICP • Adequate fixation
3. Bone Healing ?enhanced bone healing? • Exuberant callus • Heterotopic ossification Humoralosteogenic factors released by the injured brain - Klein et al ‘99 ?prolactin – Wildburger et al ?Growth Factor – Bidner et al Union rates not significantly affected while malunion rates increased
Formation of lamellar bone inside soft tissue structures where bone does not normally exist • inciting event • signal from the site of injury • supply of mesenchymal cells whose genetic machinery is not fully committed • environment which is conducive to the continued formation of new bone
Associated with ventilator dependency Avoid periarticular procedures Use approaches/techniques less associated with H.O. Prophylaxis RT – single dose within 48 hours of surgery Indomethacin – 25 mg tds for 6 weeks Excision
Occult Injuries • Fractures, dislocations and peripheral nerve injuries may be “missed” • Up to 11% of orthopaedic injuries may be “missed” • Peripheral nerve injuries are particularly common (as high as 34%) • Occult fractures in children with head injury are also common (37-82%)
Occult Injuries • Detailed physical exam with radiographs of any suspect area due to bruising, abrasion, deformity, loss of motion • Consider EMG for unexplained neurologic deficits • Bone scan advocated in children with severe head injury @ 72 hrs