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Other: Trauma - Motor Vehicle Accidents
Other: Trauma - Motor Vehicle Accidents [MVA][mvc][vehicular impact][atls]
16
Medical
02/26/2010

Additional Medical Flashcards

 


 

Cards

Term
MVA: Multiple choice question
Definition

Multiple choice question

 

A 22 year old man is examined following a motor vehice accident. His right leg is injured, as are his elbow and clavicle. Which of the following fractures or dislocations is most likely to result in an associated vascular injury?

 

a. Knee dislocation

b. Closed posterior elbow dislocation

c. Midclavicular fracture

d. Supracondylar femur fracture

e. Tibial plateau fracture

 

 

 

 

 

 

 

 

 

 

The answer is a. (Bunt, pp226-228)

 

In a four-year retrospective study of 569 at-risk parajoint fractures or dislocations resulting from blunt trauma, there was only a 1.5% incidence of associated vascular injury.

 

Angiograms and vascular surgical consultations were obtained when vascular compromise was suspected owing to clinical examination or Doppler confirmation of flow abnormalities.

 

Whie vascular injuries due to fracture on either side of a joint (eg. supracondylar femur fracture or tibial plateau fracture ) were uncommon, major joint dislocations were more commonly associated with vascular injury.

 

An exception to this rule is the type III supracondylar humerous fracture, where diplacement of bone may injure or entrap the tethered brachial artery.

 

Clavicular fractures are rarely associated with significant vascular injury.

 

The highest rate of vascular injury occurs with knee dislocations because of the extreme force required to dislocate the joint.

 

In open elbow dislocations, the brachial artery is often disrupted by forcible hyperextension of the joint; closed elbow dislocations are rarely associated with vascular injury unless the dislocationis anterior.

 

pretest surgery p.100;120 question 153

Term
MVA: Frontal Impact [ATLS]
Definition

MVA: Frontal Impact [ATLS]

 

A frontal impact is defined as a collision with an object in front of the vehicle that suddenly reduces it speed.

 

Consider two identicle vehicles traveling at the same speed. Each vehicle possesses the same kinetic energy [KE =mv²/2].  One vehicle strikes a concrete bridge abutment, whereas the other brakes to a stop. The braking vehicle loses the same amount of energy as the crashing vehicle, but over a longer time. 

 

The first energy law states that energy cannot be created or destroyed. Therefore, this energy must be transferred to another form and is absorbed by the crashing vehicle and its occupants.

 

The individual in the braking vehicle has the same total amount of energy applied, but the energy is distributed over a broad range of surfaces (eg. seat friction, foot to floorboard, tire braking, tire to road surface, and hand to steering wheel) and over a longer time.

 

ATLS, p.284

Term
MVA: Lateral impact [ATLS]
Definition

MVA: Lateral impact [ATLS]

 

A lateral impact is a collision against the side of a vehicle that accelerates the occupant away from the point of impact (acceleration as opposed to deceleration).

 

The driver who is struck on the driver's side is at greater risk for left-sided injuries, splenic injury, and left-sided skeletal fractures, including pelvic compression fractures.

 

A passenger struck on the passenger side of the vehicle may experience similar right-sided skeletal and thoracic injuries, with liver injuries being common.

 

In lateral impact collissions, the head acts as a large mass that rotates and laterally bends the neck as the torso is accelerated away from the side of the collision.

 

Injury mechanisms, therefore, involve a variety of specific forces, including shear, torque, and lateral compression and distraction.

 

ATLS, p.284

Term
MVA: Rear impact [ATLS]
Definition

MVA: Rear impact [ATLS]

 

 

Most commonly, rear impact occurs when a vehicle is at a complete stop and is struck from behind by another vehicle.

 

The stopped vehicle, including its occupants, is accelerated forward from the energy transfer from impact.

 

Because of the apposition of the seat back and torso, the torso is accelerated along with the car.

 

In the absence of a functional headrest, the occupant's head may not be accelerated with the rest of the body.

 

As a result, hyperextension of the neck occurs.

 

Fractures of the posterior elements of the cervical spine-- for example, laminar fractures, pedicle fractures, and spinous process fractures, may result and are equally distributed through the cervical vertebrae.

 

Fractures at multiple levels are common and are usually due to direct bony contact.

 

ATLS, p.284

Term
MVA: Quarter-Panel Impact [ATLS]
Definition

MVA: Quarter-Panel Impact [ATLS]

 

A quarter-panel impact, front or rear, produces a variation of the injury patterns seen in lateral and frontal impacts or lateral and rear impacts.

 

ATLS, p.284

Term
MVA: Rollover [ATLS]
Definition

MVA: Rollover [ATLS]

 

During a rollover, the unrestrained occupant can impact any part of the interior of the passenger compartment.

 

Injuries may be predicted from the impact points on the patient's skin.

 

As a general rule, this type of mechanism produces mre severe injuries because of the violent, multiple motions that occur during the rollover.

 

This is especially true for unbelted occupants.

 

ATLS, p.284

Term
MVA: Ejection [ATLS]
Definition

MVA: Ejection [ATLS]

 

The injuries sustained by the occupant during the process of ejection may be greater than when the individual hits the ground.

 

The likelihood of serious injury is increased by more than 300% if the patient is ejected from the vehicle.

 

ATLS, p.284

Term
MVA: Organ injury due to compression injuries (myocardial injury, lung parenchyma, abdominal organs, brain) [ATLS]
Definition

MVA: Organ injury due to compression injuries (myocardial injury, lung parenchyma, abdominal organs, brain) [ATLS]

 

 

Compression injuries occur when the anterior portion of the torso ceases to move forward, but the posterior portion and internal organs continue their motion.

 

The organs are eventually compressed from behind by the advancing posterior thoracoabdominal wall and the vertebral column, and in front by the impacted anterior structures.

 

Blunt myocardial injury is a typical example of this type of injury mechanism.

 

Similar injury may occur in lung parenchyma and abdominal organs.

 

In a collision, it is instinctive for the patient to take a deep breath and hold it, closing the glottis.

 

Compression of the thorax produces alveolar rupture with a resultant pneumothorax and/or tension pneumothorax.

 

The increase in intraabdominal pressure may produce diaphragmatic rupture and translocation of abdominal organs into the thoracic cavity.

 

Compression injuries to the brain may also occur.

 

Movement of the head associated with the appplication of a force through impact can be associated with rapid acceleration forces applied to the brain.

 

Compression injuries also may occur as a result of depressed skull fractures.

 

ATLS, p.284

Term
MVA: Organ injury due to deceleration injury (renal pedicle, ligamentum teres, ligamentum arteriosum - descending thoracic aorta, spleen and kidney at their pedicle junctions, liver] [ATLS]
Definition

MVA: Organ injury due to deceleration injury (renal pedicle, ligamentum teres, ligamentum arteriosum - descending thoracic aorta, spleen and kidney at their pedicle junctions, liver] [ATLS]

 

Deceleration injuries occur as the stabilizing portion of an organ (eg. renal pedicle, ligamentum teres, or descending thoracic aorta) ceases forward motion with the torso, while the movable body part (eg. spleen, kidney, or heart and aortic arch) continues to move forward.

 

In the case of the heart, shear force is developed in the aorta by the continued forward motion of the aortic arch with respect to the stationary descending aorta.

 

The distal aorta, which is anchored to the spine, decelerates more rapidly with the torso.

 

The shear forces are greatest where the arch and the stable descending aorta join at the ligamentum arteriosum.

 

This mechanism of injury also may be operative with the spleen and kidney at their pedicle junctions;

 

with the liver as the right and left lobes decelerate around the ligamentum teres, producing a central hepatic laceration;

 

and in the skull when the posterior part of the brain separates from the skull, tearing vessels and producing space-occupying lesions.

 

The numerous attachments of the dura, arachnoid, and pia inside the cranial vault effectively separate the brain into multiple compartments.

 

These compartments are subjected to shear stress by both acceleration and deceleration forces.

 

Another example is the flexible cervical spine, which is attached to the relatively immbolile thoracic spine, accounting for the frequent injury identified at the C7-T1 junction.

 

ATLS, p.284-285

Term
MVA: Trauma Alert: Adult alert 50mph rearended. 33F back and neck pain. VSS. (9/25/10)
Definition
Term

MVA: 26F, mVC, unrestrained and ejected. +LOC. 
- Head CT: Found to have right subgaleal hematoma
- CT Cspine: C7 body and left laminar fracture
- MRI spine: 3 column compression fracture of C7 with retropulsed fragments, C6-7 disruption of posterior longitudinal ligament
- CT Tspine: mild compression of T7,8,9
- Right elbow xray: Normal
- Left shoulder xray: Normal
- Management: NSG, Ortho consulted. Intubated. To OR for spinal fusion. DHT placed.
83346255  (9/14/10)

Definition
Term

MVA: 58M. MVC. ?LOC.  GCS 7 at scene.
- ETC, intubated to protect airway
- Head CT shows IPH, SAH in sylvian fissure, left frontal calvarium fracture; edematous contusionof left temporal lobe
- CT max face: lateral walls of orbits fractures, floor of right orbit, cribiform plate, bilateral laminal papyracea, left nasal bone fractures
- CT C-spine: retrolisthesis of C5, C6. DJD.
- CT C/A/P: right 3rd - 8th rib fractures
- T&L spine: Normal
- CT T/L Spine: negative
- Right ankle 3 views: comminuted fracture of calcaneus
- CT calcaneus: tibiotalar and subtalar joint subluxation
- Right forearm: Right distal diaphyseal ulnar fracture
- Consults: NSG, Ortho, Optho, OMFS, Occuloplastics, PT/OT, CDS
- Management: PICC line, Echo, EP consult for pacemaker interrogation, DHT feeds started; refresh eye drops/day, bolt, cast, Unasyn, Keppra
05082791

Definition
Term

MVA: Rollover: Ejected: +LOC. From OSH.
- CXR: normal
- Pelvic Xray: multiple fractures
- Head CT: Negative
- CT Cspine: Left occipital condyle fracture, subgaleal hematoma
- CT C/A/P: small right pneumo, Right ribs 1-5 fracture, ? right scapula fracture, AC joint separation, multiple pelvic fractures, pulmonary contusions present
- CT T-L spine: T6 fracture, L4 fracture
- CT pelvis (dedicated): Right lateral sacral fracture, right superior and inferior rami fracture, right iliac fracture extending to acetabulum
- MRI: extensive ligamentous injuriees, T4,5,7 compression injuries
- Consults: ORtho, NSG, ENT
- Management: Admit to SICU, on bipap, right chest tube placed, bloody output from tube; Reglan started for high residuals, to OR with ortho, Jewitt brace, Bactrim for UTI, Flexeril for muscle spasms
05064788 9/4/10

Definition
Term

MVA, restrained, went into ditch, hit tree. +LOC.
- CXR: Neg
- PXR: Neg
- HCT: Neg
- T-L Spine CT: L1 burst fracture
- MRI spine: L1 fracture; L3-4 intervertebral disk tear
- Knees: Left knee avulsion fracture
- Right ankle: negative
- Consults: Optho, ortho hand and trauma, NSG, maxillofacial
- Management: admitted to floor, CAMP brace and knee immobilizer, TLSO brace fitted and place
73132770 9/15/10

Definition
Term

MVA: 16M, rolled into ditch. vehicle caught on fire. crawled out the window.
- CT brain: Neg
- CT C-Spine: Neg
- Xray right hand, PA,lateral, oblique: Neg
- CXR: Neg
- Xray T&L spine: Neg
94034061  9/28/10

Definition
Term

MVA: 26M, riding motorcycle. unhelmeted, accident unwitnessed. Found 50 ft from his bike. Pt placed on spine board and c-collar was placed and he was taken to OSH. Pt arrived here intubated and sedated.
Injuries
1. Left mandibular fracture with TMJ dislocation
2. Fracture of the left lateral orbital wall.
3. Few scattered foci of right frontal subarachnoid hemorrhage.
4. Left body of scapula fracture

- CXR: Neg
- CT-head: Focal right parietal lobe hyperdensity possible devleopmental venous anomaly, no midline shift. No bleed. Left mandibular fracture. TMJ subluxation. Left scapular body fracture.
- CT C/A/P: Neg
- CT T spine: Neg
- CT L spine: Old wedge compression L1 & L2
CONSULTS:
- OMFS consulted for mandible fx - non op management
- Ortho consulted for scapula - non op management with sling for comfort
Management: 9/26 admitted to SICU, 9/27 bolt placed by NSG opening pressure 19, ICP overnight 17-7, intubated and sedated 15/5 and 40%. Keppra started 9/27. Nafcillin started 9/26. Tube feeds started 9/27. + methamphetamines.
05098269  9/26/10

Definition