What is trauma? · TRAUMA PATIENT CONFERENCE Management of Patients with Penetrating Trauma OLIVER...

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7 TH ANNUAL TREATMENT AND REHABILITATION OF THE PEDIATRIC

TRAUMA PATIENT CONFERENCE

Management of Patients with Penetrating Trauma

OLIVER LAO, MD, MPH

Presenter Disclosures

Consultant/

Speakers bureaus

No Disclosures.

Research funding No Disclosures.

Stock

ownership/Corporate boards-employment

No Disclosures.

Off-label uses No Disclosures.

What is trauma?

Trauma Epidemiology

� 38,000 Deaths in US annually due to shootings.� Mechanisms of penetrating trauma

� Knives, Arrows, Nails, etc

Penetrating TraumaYears of Potential Life Lost

18.00%

16.40%

24.80%

40.80%

Injury

Cancer

Heart Disease

All Other Diseases

MMWR 1982;31,599.

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Mechanisms of Injury: Penetrating Trauma

� Gun shot wounds

� Stab wounds

� Impalement

Gun Shot Wounds: Mechanism

� Energy transfer� Shape/size of bullet� Distance to target

� Velocity (most important)� Kinetic energy = (Mass × Velocity2 )/2

� Surface area distributed� Tumble and yaw� Fragmentation

� Anatomy� Viscoelasticity

�Muscle� organs

Stab wounds

� Mechanism

� Blunt: Crush injury

� Sharp:Tissue disruption

� Extent of Injury

� Weapon size, length, sharpness, penetration

� Severe injury

� Chest and abdomen

� 4+ wounds

� Understanding principles of energy exchange increase the Index of Suspicion associated with

the MOI

Introduction to Penetrating Trauma

� Kinetic Energy Equation

� Greater the mass the greater the energy

� Double mass = double KE

� Greater the speed the greater the energy

� Double speed = 4x increase KE

Physics of Penetrating Trauma

2

)()(2

speedVelocityweightMassKE

×=


� Small & Fast bullet can cause greater damage than large and slow.� Different bullets of different weights traveling at different

speeds cause

� Low Energy/Low Velocity

� Knives and arrows

�Medium Energy/Medium Velocity Weapons

� Handguns, shotguns, low-powered rifles

� 250-400 mps

�High Energy/High Velocity

� Assault Rifles

� 600-1,000 mps

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� Bullet spins as it travels down barrel

� Rifling in barrel

� Allows bullet to travel straight with slight yaw

� Bullet departs barrel, spinning with a slight

wobble or yaw

�Weapon forced backward and absorbs

energy

� Recoil


� Remainder of energy propels bullet forward

at a high rate of speed.

� Trajectory is curved due to gravity

� As bullet strikes object, it slows and energy

is transferred to object.

� Law of Conservation of Energy

Ballistics

� Study of the characteristics of projectiles in

motion and effects upon objects impacted

� Factors affecting energy exchange between a

projectile and body tissue� Velocity

� Profile

� Stability

� Expansion & Fragmentation

� Secondary Impacts

� Shape

Energy Dissipation

� Drag:� wind resistance

� Cavitation:� formation of a partial vacuum and cavity within a semi-fluid medium

� Profile:� Size and shape of a projectile as it contacts a target

� Larger the profile=greater energy exchange

� Expansion and fragmentation results in damage

� Stability� Allows for straighter trajectory

� Decreases after striking object results in tumbling

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Aspects of Ballistics

� Velocity� Causes Trajectory

� Faster = straighter trajectory

� Slower = more curved due to gravity


� Profile

� Portion of bullet you see as it travels towards you

� Larger profile = greater energy exchange

� Caliber

� Diameter of a bullet (ID of gun)

� 0.22 caliber = 0.22 inches

� Bullets become unstable as they pass from one medium

to another.


� Stability

� Bullet length increases bullet tumbling

� Can reduce the accuracy of the shot

� Reduced by Rifling in barrel (spinning)

� Yaw

� Gyroscopic effect on the center axis of the bullet that

reduces tumbling

� Tumbling of bullet once it strikes object

� Reduces kinetic energy

� Greater tissue damage

Bullet Gyroscopic Effect


� Expansion & Fragmentation

� Results in increased profile

� Mushrooming

� Initial impact forces may result in fragmenting

� Greater tissue damage


� Secondary Impacts� Bullet striking other objects can cause yaw and tumble

� Body Armor (Kevlar)

� Transmits energy throughout entire vest resulting in blunt trauma

� Myocardial Contusion

� Pulmonary Contusion

� Rib Fractures

� Shape� Handgun Ammunition = Blunt = Tumble

� Rifle Ammunition = Pointed = Piercing

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� Handguns� Small caliber, short barrel, medium-velocity

� Effective at close range

� Severity of injury based upon organs damaged

� Rifle� High-velocity, longer barrel, large caliber

� Increased accuracy at far distances

� Assault Rifles� Large magazine, semi- or full-automatic

� Similar injury to hunting rifles

� Multiple wounds

Specific Weapon Characteristics

� Shotgun� Slug or pellets at medium velocity

� 00 (1/3”) to #9 (pin head sized)

� Larger the load, the smaller the number of projectiles

� Deadly at close range

� Knives & Arrows� Low-energy & low-velocity

� Damage related to depth and angle of attack

� Movement of the victim can increase damage

Specific Weapon Characteristics

Damage Pathway

� Projectile Injury Process

� Tip impacts tissue

� Tissue pushed forward and to the side

� Tissue collides with adjacent tissue

� Shock wave of pressure forward and lateral

� Moves perpendicular to bullet path

� Rapid compression, crushes and tears tissue

� Cavity forms behind bullet pulling in debris with suction.

Damage Pathway

� Direct Injury� Damage done as the projectile strikes tissue

� Pressure Shock Wave� Human tissue is semi-fluid

� Solid and dense organs are damaged greatly

� Temporary Cavity� Due to cavitation

� Permanent Cavity� Due to seriously damaged tissue

� Zone of Injury� Area that extends beyond the area of permanent injury

Ballistics CavitationLow-Velocity Wounds

� Objects� Knives, Ice-picks, Arrows

� Flying objects or debris

� Injury limited to tissue impacted� Object pathway

� Object twisting or moved

� Oblique angle

� Attacker Characteristics� Males: outward and crosswise

� Females: overhand and downward

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� Density of tissue affects the efficiency of energy transmission� Resiliency

� Strength and elasticity of an object

� Connective Tissue� Absorbs energy and limits tissue damage

� Organs� Solid Organs

� Dense and low resilience

� Hollow Organs� Fluid filled: transmit energy = increased damage

� Air filled: absorbs energy = less damage

Specific Tissue & Organ Injuries

� Lungs

� Air in lung absorbs energy

� Parenchyma is compressed and rebounds

� Pneumothorax or hemothorax can result

� Bone

� Resists displacement until it shatters

� Alters projectile path

Specific Tissue & Organ Injuries

General Body Regions

� Extremities� Injury limited to resiliency of tissue

� 60-80% of injuries with <10% mortality

� Abdomen (Includes Pelvis)� Highly susceptible to injury and hemorrhage

� Bowel perforation: 12-24 hrs peritoneal irritation

� Thorax� Rib impact results in explosive energy

� Heart & great vessels have extensive damage due to lack of fluid compression

� Any large chest wound compromises breathing

General Body Regions

� Neck

� Damages Trachea and Blood Vessels

� Neurological problems

� Sucking neck wound

� Head

� Cavitational energy trapped inside skull

� Serious bleeding and lethal

Wound Characteristics

� Entrance Wounds� Size of bullet profile for non-deforming bullets

� Deforming projectiles may cause large wounds

� Close Range

� Powder Burns (Tattooing of powder)

� 1-2 mm circle of discoloration

� Localized subcutaneous emphysema

� Exit Wounds� Appears to be “Blown” outward

� Pressure wave

� Scene Size-Up� Law-Enforcement

� DO NOT ENTER UNTIL SCENE IS SAFE!

� Weapons: Victim or Assailant

� Assailants

� IF A CRIME SCENE

� DOCUMENT

� DO NOT DISTURB EVIDENCE

� RETAIN CLOTHING, ETC

� LIMIT PERSONNEL INVOLVEMENT

Special Concerns with Penetrating Trauma

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� Penetrating Wound Assessment

� Internal Organ Injury Potential

� Entrance & Exit Wounds


PROVIDE RAPID

TRANSPORT FOR ANY

GSW TO HEAD, CHEST,

OR ABDOMEN. TREAT

AGGRESIVELY FOR

SHOCK!!

Trauma is notbrain surgery!

• Air goes in & out

• Oxygen is good

• Blood goes round & round

• Stop bleeding

• Put things back where and how they belong

A-B-C-D-E

Initial Assessment: Primary Survey

•A = Airway

•B = Breathing

•C = Circulation

•D = Disability

•E = Exposure

• Clear & establish a good airway–Consider intubation for coma, shock, and neck/thoracic injuries

• C-spine stabilization

Initial Assessment: Airway

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• Clear & establish a good airway–Consider intubation for coma, shock, and neck/thoracic injuries

• C-spine stabilization

Initial Assessment: Airway

Airway: Cricothyrotomy

Initial Assessment: Breathing

� Chest excursion & breath sounds

� Flail chest

� Pneumothorax

� Open

� Tension

� Massive Hemothorax

Initial Assessment: Circulation

• Perfusion (mental status, skin, pulse)

• Control bleeding with pressure

• Pericardial Tamponade

–Beck’s Triad

• Establish 2 large bore (16G or larger) IV’s in upper extremity peripheral veins

• Resuscitate with Lactated Ringers

–After 4 L think about resuscitation with blood

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Initial Assessment: Disability

• Neurologic status

–Glasgow Coma Scale

• Eye

•Motor-best predictor of long term outcome

• Verbal

–Spinal Cord Injury

Initial Assessment: Exposure

• Remove clothes

• Temperature

–warm blankets

• Finger and tube in every orifice

• Maintain full spine precautions

–Log Roll

Initial Assessment:Exposure

• Stabilize Fractures

• Relocate dislocated joints

• Reassess pulses

Secondary Survey• Patient history

• Head to toe physical exam

• Radiography

–Lateral C-spine, C-xray, pelvis

–One cavity above/below entrance/exit wounds

–FAST

• Urinary bladder drainage

• NGT

• Blood sampling/monitoring

� Penetrating Wound Care� Facial Wounds

� Difficult intubations

� Depress chest

� Pass ET through bubbling tissue

� Consider LMA and Combitube

� Consider Cricothyreotomy & Cricothyreostomy

� Chest Wounds� Pneumothorax

� 2/3” the diameter of the trachea or larger to entrain air

� 3-sided occlusive dressing

� Needle Decompress

� Pericardial Tamponade


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� Impaled Objects

� Low-energy

� Dangerous to remove

� DO NOT REMOVE

� UNLESS

� In Cheek

� Interferes with CPR: ASSESS!!!

Special Concerns with Penetrating Trauma Neck


• Oxygen is good


• Stop bleeding


A-B-C-D-E


•A = Airway

•B = Breathing

•C = Circulation

•D = Disability

•E = Exposure

ETIOLOGY

� Stab wounds (SW) vs gunshot wounds (GSW)

� In the civilian sector, SWs account for 55-70% of the injuries.

� GSWs carry a higher morbidity and mortality.

� The morbidity and mortality of GSWs depend on the characteristics and velocity of the missile.

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Penetrating Neck

Among all penetrating neck wounds, the following occur:

�Major vascular injury: 15–25% Internal Jugular vein injured most

commonly

�Laryngotracheal injury: 10-15%

�Pharyngeal or esophageal injury:

7%

�Spinal cord injury: 10-15% of GSW, rare in SW

Anatomy� III – Base of skull to Angle of Mandible: distal internal carotid and vertebral vessels, cranial nerves, parotid gland, nasopharynx

� II - Angle of mandible to cricoid cartilage: carotid and vertebral vessels, larynx, trachea, esophagus, vagus and recurrent laryngeal nerves, spinal cord

� I - Cricoid cartilage to clavicles: great vessels of upper chest, upper lung, esophagus, trachea, thoracic duct, cervical nervous system

In stable patients, management varies based on Zone of injury.

Stable or Unstable?

� Airway, Breathing, Circulation

� BP < 90 which poorly responds to volume = Unstable patient

-CXR to help determine trajectory/op approach

-To the OR

ZONE II INJURY – STABLE PATIENT

Physical exam – the most essential portion of the evaluation

“Hard” clinical signs:-Active bleeding-large, pulsatile, &/or expanding hematoma-cervical bruit or thrill-central neurologic deficit

These “hard” clinical signs strongly predict presence of major vascular injury and generally mandate operative or other therapeutic intervention.

ZONE II INJURY – STABLE PATIENT

� If no “hard” clinical signs of vascular injury are present, a growing body of evidence supports simple

observation of these patients.

� Simple observation of stable Zone II patients without “hard” clinical signs has a missed injury rate of 0.6%. (8 studies, 1216 total pts, 837 observed)

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ZONES I AND III INJURY – STABLE PATIENT

� Physical exam is less reliable in Zones I and III

� Routine arteriography for both diagnosis, localization, and possible (Zone III) treatment

� Routine esophagography or esophagoscopy in Zone I injury

OR

� Zone I injury, site unclear:

median sternotomy is the most versatile incision. May extend incision up the neck or out laterally

infraclavicularly

� Zone II injury:

Standard anterior neck incision

� Zone III injury

Standard anterior neck incision

in the OR, ZII or III

� Pt supine, neck extended, rotated away from injured side

� Surgically prepare and drape to include a potential

median sternotomy incision

� Incision made anterior to the sternocleidomastoid

muscle

� Expose carotid arteries, internal jugular vein to elucidate source of hemorrhage

Chest


• Oxygen is good


• Stop bleeding


A-B-C-D-E

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•A = Airway

•B = Breathing

•C = Circulation

•D = Disability

•E = Exposure

Spaces

Cardiac Box

� Superior: clavicles

� Inferior: costal margins

� Lateral: midclavicular line

Penetrating Cardiac Injuries

� More proximal coronary artery lacerations require coronary bypass. Rarely, the interventricular

septum, a valve, papillary muscle, or chordaetendineae is lacerated, producing an acute shunt or valvular insufficiency. These lesions are poorly tolerated and can quickly produce massive

pulmonary edema and cardiogenic shock

Penetrating Cardiac Injuries Prognosis

� Several factors adversely affect survival. These include GSW mechanisms and wounds that involve the left ventricle, multiple cardiac chambers, intrapericardial great vessels, or one or more coronary arteries. Factors favorable to survival include stab wound mechanisms with minor perforations, isolated right ventricular wounds, a systolic blood pressure greater than 50 mm Hg on arrival at the ED, and the presence of cardiac tamponade.

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Cardiac Tamponade

� Beck’s triad: muffled heart sounds, hypotension, and distended neck veins may be seen in only 10 percent of patients

� Pulsus paradoxus: a substantial fall in systolic blood pressure during inspiration

� Kussmaul sign: increase in jugular venous distention on inspiration

� Narrowing of the pulse pressure and elevated CVP

Complications

� Coronary artery injury (5-9%)

� Valvular apparatus dysfunction (0.2-9%)

� Intracardiac fistulas (1.9%)

� VSD

� ASD

� Atrioventricular fistulas

� Arrhythmias

� Delayed cardiac tamponade (1 hr to 76 days)

Treatment Algorithm ED Thoracotomy

Thoracic Injuries Thoracic Injuries

� Life threatening injuries:

� Air

� Blood

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Thoracic Injuries: Air Thoracic Injuries: Needle Decompression

Thoracic Injuries: Blood Thoracic Injuries: Sucking Chest Wound

Abdomen


• Oxygen is good


• Stop bleeding


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A-B-C-D-E


•A = Airway

•B = Breathing

•C = Circulation

•D = Disability

•E = Exposure

Penetrating Abdominal Trauma

GSW KSW

OR HD Unstable HD Stable/No peritonitis

OR Peritoneal Penetration

Positive Negative

OR Observation

Penetrating Abdominal Trauma

Abdominal Trauma

Abdominal Trauma Abdominal Trauma

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Abdominal Cavity Abdominal Trauma?

Pelvic Injury

�Introduction

� significant blood loss if bilateral

�may settle in retroperitoneal space

�3% of all fractures

�mortality 8 - 50%

�2ndmost common cause of traumatic death

Pelvic Fracture

� Signs & Symptoms

� pelvic instability

� pain (suprapubic also)

� crepitus

� bloody meatus

� neurovascular deficits


• Oxygen is good


• Stop bleeding


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A-B-C-D-E


•A = Airway

•B = Breathing

•C = Circulation

•D = Disability

•E = Exposure

Pelvic Injury: MAST Pelvic Injury: Sheet

Pelvis

�Interventions�Stable patient

�analgesia

�Repair vs mobilization

�Unstable patient�Immobilize

�Ex-fix

�Angiography�embolization

Extremity/Vascular Injury

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Extremity/Vascular


• Oxygen is good


• Stop bleeding


A-B-C-D-E


•A = Airway

•B = Breathing

•C = Circulation

•D = Disability

•E = Exposure

Extremity/Vascular: Tourniquet Extremity/Vascular: BP Cuff

What is trauma? · TRAUMA PATIENT CONFERENCE Management of Patients with Penetrating Trauma OLIVER...

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Transcript of What is trauma? · TRAUMA PATIENT CONFERENCE Management of Patients with Penetrating Trauma OLIVER...