Presentation on theme: "CHEST TRAUMA MI Zucker, MD. A dr Z Lecture On Major Chest Trauma In Three Parts."— Presentation transcript:
CHEST TRAUMA MI Zucker, MD
A dr Z Lecture On Major Chest Trauma In Three Parts
Chest trauma Blunt Penetrating Explosion Related Chemical Agent Related Biological Agent Related
Oh, yeah: There’s a separate lecture on Traumatic Aortic Injury
But first: A few comments on Trauma Imaging
Trauma Chest Radiograph Usually AP, often supine, frequently in poor inspiration. So, a challenge to interpret.
CT Chest More sensitive and specific
CT Chest: Reformat The new MDCT scanners do awesome reformats without additional scanning.
Part the First: BLUNT TRAUMA
Fractures and Dislocations Spine Ribs Clavicles Sternum Shoulders
Spine Injuries Look for loss of alignment, fractures and paraspinal hematoma. The findings may be very subtle.
Rib Fractures In themselves, not too much of a problem, but may be an indicator of underlying pleura, lung, liver, spleen, kidney injuries.
Flail Chest Multiple rib fractures, especially if individual ribs fractured more than once, may cause paradoxical motion. The major problem actually is associated pulmonary contusion.
Clavicle Injuries Fractures not usually much of a problem
Sterno-Clavicular Dislocations Anterior: Not much of a problem Posterior: Less common; can injure great vessels or trachea
Sterno-clavicle joint dislocation
Sterno-clavicle dislocation: CT
Shoulder Injuries Look particularly for dislocations and scapula fractures
CT Needed if Scapula Fracture Seen
Sternum Fractures Not usually a problem. Controversial association with myocardial injury.
AIR where it shouldn’t be Pneumothorax Pneumomediastinum Subcutaneous emphysema Systemic venous air embolism Pneumopericardium Pneumoperitoneum/retroperitoneum
PNEUMOTHORAX Simple Tension Open
PNEUMOTHORAX: CT Much more sensitive than plain films. Even a small traumatic pneumothorax is important, especially if patient mechanically ventilated or going to OR: A simple pneumothorax can be converted into a life- threatening tension pneumothorax.
Pneumothorax: Simple Erect AP/PA view best Visceral pleural line No vessels or markings Variable degree of lung collapse No shift
PNEUMOTHORAX: Tension Erect AP/PA view best Shift of mediastinum/heart/trachea away from PTX side Depressed hemidiaphragm Degree of lung collapse is variable
PNEUMOTHORAX: Supine Supine AP view has limited sensitivity: 50% Deep sulcus sign Too sharp heart border/hemidiaphragm sign Increased lucency over lower chest Subpulmonic air sign Can see vessels
PNEUMOTHORAX on Supine View: Visceral pleural line
PNEUMOTHORAX on Supine View: Deep sulcus sign
PNEUMOTHORAX on Supine View: Why vessels are visible
PNEUMOTHORAX on Supine View: Subpulmonic sign
CT: subpulmonic sign explained
PNEUMOTHORAX: Open A large hole in the chest caused by a large low velocity missile. Air enters the hole rather than the trachea causing hypoxia.
PNEUMOMEDIASTIUM Usually from ruptured alveoli. Can also be from trachea, bronchi, esophagus, bowel and neck injuries.
PNEUMOMEDIASTINUM: Signs Linear paratracheal lucencies Air along heart border “V” sign at aortic- diaphragm junction Continuous diaphragm sign
PNEUMOMEDIASTINUM: Paratracheal lucencies
PNEUMOMEDIASTINUM: Continuous diaphragm sign
Trachea/bronchi injuries Tears occur within 2cm of carina Persistant pneumothorax Large pneumomediastinum “Fallen lung”
Subcutaneous Emphysema Causes: Same as pneumomediastinum
Pneumoperitoneum Pneumoperitoneum and sometimes pneumo- retroperitoneum are seen on upright chest film, but occasionally are visible on supine chest radiograph.
Systemic Venous Air Embolism Tears in airspaces with resulting communication with veins; or outside access to systemic veins Often lethal: Air block in heart or coronary, cerebral, mesenteric, peripheral arteries.
Systemic Venous Air Embolism
HEMOTHORAX Venous or arterial bleeding 60% controlled by chest tube, 40% need operative management Can miss hundreds of cc’s on supine film Can be tension
PULMONARY CONTUSION and LACERATION Contusion: Blood in intact lung parenchyma Laceration: Blood in torn lung parenchyma Can’t tell difference on chest film. Contusions peak in 2-3 days, begin to resolve in a week; lacerations take much longer to resolve and may leave scars
Pulmonary Contusion and Laceration
CT: Pulmonary Contusion
CT: Pulmonary laceration The tear in the lung can fill with blood or air.
DIAPHRAGM Injuries 5% of major blunt trauma, also thoraco- abdominal penetrating trauma Left clinically injured more than right 60/40 Sensitivity of Chest film 40%. CT better, but still misses some Hard signs: NGT through g.e. junction then up into chest, and hollow viscus above diaphragm Soft signs: Indistinct diaphragm, effusion, atelectasis
Diaphragm Injury: Position of NG Tube
Diaphragm Injury: Gut in Chest
Part the Second: PENETRATING TRAUMA Gunshot Wounds Stab Wounds
Gunshot Wounds Match all entrance and exit wounds Find the bullet(s) and keep looking until all are accounted for Estimate path of bullet, which may not be straight Estimate organs injured
INJURIES depend upon: Caliber, weight, construction of bullet Velocity Tissue impacted
Gunshot Wounds: some terms Rounds: the bullet and its casing, propellant and primer Bullet: the part of the round that is propelled from the weapon Firearms: pistol, rifle, shotgun “Blast” : a property of high explosives, not firearms. Don’t use with GSW.
Rounds: Pistol and Rifle
BULLET Size: diameter in millimeters or caliber (fractions of an inch) Weight: in grains Construction: round nose, hollow point, full metal jacket, semi-jacket, no jacket
Injuries: Bullet The larger the diameter of the bullet and the more it weighs, the bigger the wound. Hollow point and semi-jacket bullets mushroom or fragment on impact and cause bigger wounds than FMJ.
Injuries: Velocity Hand guns are low velocity (1000 fps) and cause a permanent wound channel (crush) only. High-powered and assault rifles are high velocity (3000 fps) and cause a permanent wound channel and also temporary cavitation (blunt or stretch trauma) and so a bigger wound.
Injuries: Tissue Lung is elastic and more resistant to injury than solid organs. Bone is least resistant. Obviously, the more vital the organ the more serious the injury.
Gunshot Wounds GSWs of the CHEST cause: pulmonary lacerations/contusions, hemothorax, pneumothorax, mediastinum/heart injuries, pneumomediastinum, fractures.
Gunshot Wounds: CT Experimental May be able to establish bullet tract and avoid surgery, especially thoraco- abdominal wounds
Knife wounds All low energy, small diameter wounds. Frequently, superficial stab or slash. Look for lung laceration, pneumothorax, hemothorax, pneumomediastinum, abnormal contour of mediastinum or heart. Path of wound is straight.
Knife Wound: PTX
Part the Third: Explosions Chemical events Biological events
Since, so far, Los Angeles has experienced few of these events, most of the images are simulations
Radiological Events We aren’t going to discuss these today. An isotope combined with an explosive makes a Radiological Dispersion Device. In an RDD event, all of the immediate casualties would be from the explosion. Radiation injuries would be delayed to negligible, depending upon the type and amount of the isotope.