TRAUMATIC CHEST

CONTENTS

•ANATOMY

•MECHANISM OF INJURY

•EFFECT OF INJURY

•TECHNIQUE OF RADIOGRAPHIC PROJECTION

•RADIOLOGICAL SIGN:
-Thoracic cage injury
-Hyperlucent chest
-Opaque chest
-Mixed lucent and opaque chest
-Diaphragmatic injury
-Solid organ injury

•OUTCOME OF TRAUMATIC CHEST

ANATOMY
•ANATOMY – GROSS vs RADIOGRAPHIC
•Thoracic cage:
Static – anterior: sternum
posterior: thoracic spine, scapular.
lateral: ribs, clavicle.
•Content: mediastinum – superior, anterior, middle and posterior.
Lung parenchyma
Pleura – negative pressure.

UNDERSTANDING ANATOMY
•Gross anatomy - air spaces, bronchial tree, interstitium, vascular system, lymph nodes / lymphatic system, pleural reflection, thoracic cage.
•Radiographic anatomy – opaque (interstitium, lymph nodes, vascular system, thoracic cage ) and lucent (air spaces, bronchial tree).

LOBAR AND SEGMENTAL BRONCHUS: RIGHT LUNG






















•Main bronchus – steeper, shorter, wider.
•3 lobar, 10 segmental bronchus – upper (3), middle (2), lower (5).
•Bronchioles – 6-20 division of segmental bronchus.
•Upper lobe bronchus – 2.5 cm after bifurcation.

LOBAR AND SEGMENTAL BRONCHUS: LEFT LUNG























•Main bronchus – less steeper, longer.
•2 lobes, 9 segmental – upper (5), lower (4) medial basal.Upper lobe bronchus – 5 cm after bifurcation

PLEURA
•Parietal pleura – lining the thoracic cavity.
•Visceral pleura – investing the lung.
•Fissure: 2 layers of visceral pleura – oblique (both sides) and transverse (right only).
•Accessory lobe: azygous, posterior accessory (left), inferior accessory (right), middle lobe (left) – 4 layers of pleura.
•Costophrenic angles: most dependent space – 50 ml obliterate posterior, 100-150 ml obliterate lateral.

MECHANISM OF CHEST TRAUMA

•DIRECT INJURY:
BLUNT CHEST TRAUMA.
PANETRATING CHEST TRAUMA.
BARO TRAUMA.
RADIATION TRAUMA.

•INDIRECT INJURY:
COMPLICATION OF REMOTE INJURY.
COMPLICATION OF TREATMENT.

DIRECT CHEST TRAUMA

•BLUNT CHEST INJURY:
Causes:
MVA (75%), fall, blow, blast, violent action.
30% require hospital admission.
A quarter of thoracic injuries attribute to deaths.

•PENETRATING INJURY:
Causes:
Fracture of rib, gunshot, stab.
Permanent cavity inside the tissue, crushed, expansion.
Projectile passes through – tract.

•RADIATION INJURY:

•BAROTRAUMA:

EFFECT OF CHEST TRAUMA

•Chest wall injuries (e.g, rib fractures): breathing difficult compromise ventilation.
•Direct lung injuries: pulmonary contusions impair ventilation.
•Space-occupying lesions: pneumothoraces, hemothoraces, and pneumohemothoraces interfere oxygenation and ventilation.

•Tension pneumothorax: decreased blood return to the heart, circulatory compromise.
•Cardiac or severe great vessel injuries:
exsanguination hypovolemic
loss of cardiac function cardiogenic shock / death.
•Shunting and dead space ventilation.

TECHNIQUE OF RADIOGRAPHIC PROJECTION

•CXR is the initial study of choice – preferably AP erect view.
•CXR in expiration – detecting small pneumothorax.
•AP supine radiograph at the end of inspiration.
•Decubitus view – assess pleural fluid, pneumothoracis, hydropneumothorax.
NOTE: supine radiograph is most difficult to analyse, under reporting is common.

TRAUMATIC CHEST:RADIOLOGICAL SIGNS

•Isolated sign not common…. combination
•Fracture rib might cause major injury to the lung parenchyma (contusion, laceration and hemorrhage) and other complications.

•Thoracic cage injury
•Hyperlucent chest
–Pneumothorax
–Pneumomediastinum
–Pneumopericardium
–Subcutaneous emphysema
•Opaque chest
–Lung contusion / laceration
–Hemothorax
•Mixed lucent and opaque chest
–Hemopneumothorax
–Pneumothorax and compressive collapse
•Diaphragmatic injury
•Solid organ injury

THORACIC CAGE INJURY

•Chest wall fractures – Rib
most frequent 4-10.
fractures 8-12 ribs, should raise the suggestion of associated abdominal injuries.
•Flail chest
fractured 2 or more places.
Bilateral rib fracture.
Affected wall sunken in during inspiration.
•1st to 3rd rib fractures require excessive energy – often associated with major intrathoracic injury and it’s complication such as cranial, major vascular and abdominal injuries.

•Complication of rib fracture: fracture end could penetrate underlying structures and cause several complications:
1. pulmonary contusion, laceration or hemorrhage
2. pneumothorax
3. hemothorax
4. hemopneumothorax
5. surgical emphysema

•Clavicle fractures - most common injuries to the chest wall and shoulder girdle. 80% occur in the middle third of the clavicle.
•Sternal fractures.
•Scapular injury.

FRACTURE OF CLAVICLE

•Fracture lateral of right and middle left third clavicle.

FRACTURE RIB AND CLAVICLE

FRACTURE RIB