Chest Trauma, EM Ch 24

1. Purple-bluish color of face and neck. 2. Subconjunctival and retinal hemorrhages common. 3. Loss of consciousness or neurological abnormalities caused by cerebral hypoxia. 4. Intracerebral bleeds uncommon. 5. *Clinical significance* intrathoracic injuries associated with severe crushing force.

Diagnosis of traumatic asphyxia.

1. Sudden cardiac death or near sudden cardiac death after blunt, low-impact chest wall trauma without cardiac abnormality. Usually from a baseball, softball, hockey puck, or other hard objects. 2. Ventricular fibrillation is the most common arrhythmia. 3. Young, male athletes ages 5-18 most common. 4. Death is instantaneous and successful resuscitation is uncommon.

Commotio cordis

1. When a segment of the chest does not have bony contiguity with the rest of the thoracic cage. Usually fractures involving 3 or more rib fractured in two different places. 2. Inspiration, negative thoracic pressure, flail segment moves inward. Tidal volume goes down. 3. May cause respiratory failure from underlying pulmonary injury.

Flail chest pathophysiology

1. Assess ABCs. 2. Put on 100% oxygen non-rebreather mask. 3. *Occlusive dressing* placed immediately over wound. Must cover wound edges. *Only tape 3 sides* so air can escape, but not re-enter. 4. Placement of a chest tube. 5. Definitive treatment includes chest tube placement and wound closure.

Open pneumothorax treatment

1. Witnessed cardiopulmonary arrest in ED. 2. Lose signs of life during short transport to ED. 3. Survival rates better cardiac injuries and stab wounds better. 4. Survival rates worse for noncardiac injuries and gunshot wounds.

Best uses of thoracotomy.

1. Blood loss. 2. Increased intrapleural pressure. 3. Blood in the pericardial sac. 4. Vascular dysfunction. 5. Pericardial dysfunction.

Causes of abnormal circulation:

1. Chest wall or muscular problems related to pain or trauma. 2. Gas exchange problems from atelectasis, contusion, respiratory tract disruption. 3. CNS problems related to drugs or trauma.

Chest wall causes of breathing abnormalities:

1. Penetrating trauma with no signs of life in the field. 2. Blunt trauma with no signs of life on arrival to ED. 3. Not indicated unless qualified surgical backup present.

Contraindications to thoracotomy.

*IDENTIFIED ON SECONDARY SURVEY* 1. Often missed diagnosis. 2. SSX: Most common dyspnea and subcutaneous emphysema of neck or upper thoracic region. May also have hoarseness, hemoptysis, hypoxia, and persistent pneumothorax even with thoracostomy tube. 3. Diagnostic studies: CXR: Subcutaneous emphysema, pneumomediastinum, pneumothorax, and peribronchial air.

Diagnosis of tracheaobronchial injury.

1. Consider in patients with rapid deceleration accidents, including speeds greater than 30 mph and falls greater than 10 feet. Risk factors include age greater than 50, unrestrained driver, ejected passenger, pedestrians struck by vehicle. 2. SSX: Includes chest pain, back pain, dyspnea, hoarseness, intrascapular mumur, extremity pain caused by ischemia. *PSEUDOCOARCTATION: Hypertensive upper extremities and hypotensive lower extremities including minimal blood pressure and pulse deficits. Many have no signs of chest trauma. * 3. Diagnostic studies: CXR: Good for screening, but normal in some. Most common finding is *mediastinum widened more than 8 cm*. Also noted findings include indistinct aortic knob, left mainstem bronchus depression, trachial deviation to the RIGHT, NG tube deviation, widening of the paratracheal stripe, apical capping, obliteration of space between pulmonary artery and aorta. Angiography: gold standard, but expensive and not used anymore. *Do CT first.* Chest CT: Newer scanners, use of IV contrast, and consistent protocols, diagnosis approaches 100%.

Diagnosis of aortic disruption.

*IDENTIFIED ON PRIMARY SURVEY* 1. SSX: Nonspecific signs and symptoms. 2. Physical exam: Typically have tachycardia and narrow pulse pressure, but not always. 3. Beck's triad in blunt trauma includes hypotension, distended neck veins, and muffled heart tones. 4. JVD may be absent in hypovolemia. 5. FAST for rapid detection of pericardial fluid. 6. Stable patients only can have transthoracic or transesophageal echocardiogram which helps detect hemodynamic impact. CT is NOT PREFERRED because it cannot tell hemodynamic impact.

Diagnosis of cardiac tamponade.

*IDENTIFIED ON SECONDARY SURVEY* 1. SSX: Asymptomatic acutely or may have symptoms of bowel obstruction. Delayed presentation. Nonspecific bowel or respiratory complaints. Diagnosis is often missed. 2. Diagnostic Studies: CXR: Good screening tool, 50% acute and 100% identified on delayed presentation. Findings on CXR include: Elevation or irregularity of the diaphragmatic border. Unilateral pleural thickening. Obvious herniation of abdominal contents into chest cavity. Presence of NG tube in chest cavity. CT scan: Often used before surgery, but not great diagnostically. The right diaphragm follows the contour of the liver and is hard to see.

Diagnosis of diaphragmatic hernia.

*IDENTIFIED ON SECONDARY SURVEY* 1. SSX: Nonspecific and masked by other serious injuries. Suspect in patients with neck, thoracic, back, or abdominal injuries. Complaints of throat pain, dysphagia, odynophagia, hoarseness, choking, chest pain, hematemesis, dyspnea, continued neck pain even with treatment and immobilization. 2. Physical exam: Neck redness, swelling, unexplained tachycardia, subcutaneous emphysema of neck or chest, bloody NG tube contents. 3. Diagnostic studies: CXR finding suggestive of esophageal injury include pneumomediastinum, widened mediastinum, LEFT pleural effusion. BEST TESTS: Gastrograffin followed by barium swallow and esophagoscopy. 4. May need exploratory surgery for definitive diagnosis.

Diagnosis of esophageal disruption.

*IDENTIFIED ON PRIMARY SURVEY* 1. SSX: Pain and respiratory distress. 2. Physical Exam: Tachypnea and shallow respirations. Paradoxical chest wall movement may or may not be seen. Crepitus often present. NOTE: The patient may be able to compensate by hyperventilating and splinting of the chest wall.

Diagnosis of flail chest

*IDENTIFIED ON PRIMARY SURVEY* 1. SSX: Respiratory distress, tachypnea, variable hypoxia. 2. Physical Exam: Dullness to percussion and decreased breath sounds on affected side. Possible hypotension and flat neck veins. Possible narrowed pulse pressure. 3. Diagnostic studies. CXR in small hemothorax, less than 350 ml, shows a small chest effusion on upright. CXR in moderate hemothorax, between 350 and 1500 mL, shows diffuse opacity affected side. CXR in massive hemothorax, greater than 1500 mL, shows ground glass appearance.

Diagnosis of massive hemothorax.

*IDENTIFIED ON SECONDARY SURVEY* 1. SSX: Chest pain, subtle ECG changes, hypotension related to cardiac dysmotility. 2. Diagnostic studies: ECG: Good screening tool for those with chest trauma and associated chest pain, unexplained hypotension, and coronary artery disease. Most common finding on ECG is SINUS TACHYCARDIA with nonspecific ST and T wave changes. May see: RBBB, A. fib, A. flutter, PVCs, V. tachycardia, V. flutter. NOTE: Very few patients with normal ECGs develop complications from myocardial contusion. BIOCHEMICAL MARKERS: Not useful. ECHOCARDIOGRAPHY: Not useful for myocardial contusion, but can be used to identify cardiac tamponade and ventricular rupture.

Diagnosis of mycardial contusion.

1. Acquire information about weapon, length, caliber, distance, and amount of hemorrhage at the scene. 2. Assess for vascular injuries by noting unequal BP of extremities, new vascular bruits, and the classic signs of pericardial tamponade. 3. Pericardial tamponade SSX include distended neck veins, hypotension, and muffled heart sounds. 4. Diagnostic studies: CXR immediately to identify pneumothorax, hemothorax, or foreign body. Put radio-opaque marker at wound entry and exit sites. FAST exam to evaluate for pericardial tamponade to determine if emergency thoracotomy is indicated. 5. Can produce the same life-threatening injuries as blunt trauma.

Diagnosis of penetrating chest trauma.

1. SSX: Includes pleuritic midline chest pain, focal tenderness over the sternum. There should be NO pulmonary compromise. 2. Pulmonary contusions or blunt cardiac injury may be associated with sternal fracture. 3. Rare complication of sternal fracture is *posterior sternoclavicular dislocation* which can result in mediastinal displacement of the clavicular heads which can *obstruct superior vena cava*.

Diagnosis of sternal fracture.

1. SSX: Includes hemoptysis, circulatory and CNS dysfunction after positive-pressure ventilation. 2. Common: Focal neurologic abnormalities in absence of head injury. 3. Suggestive of air embolism: Circulatory arrest after mechanical ventilation. 4. Physical Exam: Fundoscopic exam air in the retinal vessels. 5. Diagnostic studies: *Air in ABG* that is not due to froth is *DIAGNOSTIC*. TEE can be used as a diagnostic tool.

Diagnosis of systemic air embolism.

*IDENTIFIED ON PRIMARY SURVEY* 1. SSX: respiratory distress, tachypnea, and hypoxia. 2. Physical Exam Findings: Hyperresonance to percussion on affected side. Decreased or absent breath sounds on affected side. Tracheal deviation away from affected side. *Neck veins distended in NORMOVOLEMIC patient. May not be present if hypovolemic*. 3. The diagnosis is *CLINICAL. Do not wait for CXR!* 4. If the patient is stable, and suspected you may do CXR. 5. Diagnostic ultrasonography for rapid identification (86-98%sensitive).

Diagnosis of tension pneumothorax.

Hypovolemic shock is often caused by blood loss, need to start adequate fluid resuscitation. Early interventions should be aimed at ventilating and perfusing the lung that is still capable of ventilation and perfusion.

Important points to know for chest trauma treatment

1. Penetrating thoracic wound in agonal state or recent loss of vital signs. Deterioration or cardiac arrest after care has been initiated. Uncontrolled hemorrhage from thoracic inlet or out of chest tube. 2. Need for open cardiac massage. Occlusion of the descending thoracic aorta to provide increased blood flow to heart or brain prior to laparotomy. 3. Suspected subclavian vessel injury with intrapleural exsanguination.

Indications for thoracotomy.

1. Tension pneumothorax. 2. Open pneumothorax. 3. Cardiac tamponade. 4. Flail chest.

Life threatening thoracic injuries identified on primary survey:

1. Pulmonary contusion. 2. Myocardial contusion. 3. Diaphragmatic hernia. 4. Esophageal disruption. 5. Aortic disruption. 6. Tracheobronchial injury.

Life threatening thoracic injuries identified on secondary survey:

1. Intrapleural bleeding or hemothorax caused by injury to chest wall, great vessels, or lung. 2. Definition: massive hemothorax with accumulation of greater than 1000-1500 mL blood or 1/3 or more of the patients blood volume in chest cavity. 3. Most common mode of injury: penetrating injury that disrupts pulmonary or systemic blood vessels. 4. Respiratory insufficiency depends on blood lost. 5. With massive injury, *collapsed lung with RIGHT TO LEFT SHUNT*. 6. Circulatory compromise.

Massive hemothorax pathophysiology

*IDENTIFIED ON PRIMARY SURVEY* 1. Large penetrating wound from trauma. 2. Equilibrium between intrathoracic and atmospheric pressure. Negative intrathoracic pressure is needed, but can't be maintained. 3. Air enters chest wall and not lungs causing severe hypoxia. 4. Immediate treatment necessary.

Open pneumothorax pathophysiology

1. Small, frequent doses of narcotic medications. 2. Assess pain control constantly to make sure controlled.

Pain medication management in chest trauma:

1. Blood in the pericardium. Can be induced by as *little as 200 mL*. 2. Increased intrapericardial pressure with heart compression which DECREASES CARDIAC OUTPUT. 3. Decreased cardiac output, decreased venous return, decrease cardiac filling. 4. Increased PRESSURE may lead to DECREASED myocardial perfusion. 5. May induce hypotension and shock.

Pathophysiology for cardiac tamponade.

1. Common cause of death in blunt trauma from rapid deceleration and shear forces from MVAs, falls, and crushes. 2. Most commonly involves *DESCENDING SEGMENT of aorta just past the origin of the left subclavian artery.* 3. Rapid treatment is essential, most patients die.

Pathophysiology of aortic disruption.

1. Result from direct diaphragmatic injury OR intrabdominal or intrathoracic pressure resulting in rupture of diaphragm. 2. Left side affected 3 times more because liver protects right. 3. Delayed presentation and presents its ugly head when herniation of abdominal contents come through the diaphragm causing obstruction, incarceration, strangulation, perforation, and death. Delayed presentation can occur up to 50 years after primary traumatic event. 4. The diaphragm DOES NOT spontaneously heal.

Pathophysiology of diaphragmatic hernia.

1. Secondary to blunt trauma. Most commonly occurs with high speed MVA. 2. Complications include mediastinitis, pericarditis, pneumonitis, empyema, and aortic aneurysm.

Pathophysiology of esophageal disruption.

1. Contusions are distinct areas of hemorrhage. They can be subendocardial, but may be transmural. 2. Noted to have wall motion abnormalities which can lead to dysrhythmias. Could also cause a decrease in cardiac output which leads to cardiogenic shock.

Pathophysiology of mycardial contusion.

1. Usually caused by *stabbing ASCENDING AORTA*, or by gunshot to DESCENDING AORTA. 2. May cause lacerations of pericardium or any thoracic great vessels.

Pathophysiology of penetrating chest trauma.

1. One way valve. 2. Air enters, but cannot leave the pleural space. 3. Increased intrapleural pressure collapses the lung and *shifts mediastinal contents away from the injury*. 4. Causes a *RIGHT TO LEFT* pulmonary shunt with resultant hypoxia. 5. Increased intrathoracic pressure and pressure on vena cava can cause REDUCED VENOUS RETURN and can lead to DECREASED CARDIAC OUTPUT and SHOCK.

Pathophysiology of tension pneumothorax.

1. Injury to the trachea or bronchus most often resulting from MVA and crush injuries. 2. RIGHT sided more common and more severe, and great majority occur within 2 cm of the carina. Often a missed diagnosis.

Pathophysiology of tracheobronchial injury.

Severe crush injury of the thorax and abdomen can cause retrograde flow from *right heart to great veins of head and neck*.

Pathophysiology of traumatic asphyxia.

*IDENTIFIED ON SECONDARY SURVEY* 1. Often silent. Suspect if significant chest trauma. 2. *MOST IMPORTANT SIGN IS HYPOXIA.* The degree of hypoxia relates directly to size of contusion. 3. SSX: Hypoxia, dyspnea, hemoptysis, tachycardia. 4. Physical exam: Palpable rib fractures, chest wall bruising, decreased breath sounds, crackles. 5. Diagnostic studies: CXR: Will miss substantial numbers of pulmonary contusion, but radiographically apparent within 6 hours. Thoracic CT: Follow CXR with CT if suspected.

Pulmonary contusion diagnosis.

1. Lung parenchymal injury with hemorrhage and edema without associated laceration. 2. Occur with blunt chest trauma, often associated with rib fractures or flail chest, but not necessarily. 3. Complications include pneumonia, ARDS, and disability. 4. Associated conditions such as COPD lower threshold for early intubation.

Pulmonary contusion pathophysiology.

1. CXR screening tool of choice, but not all can be seen. 2. CT scan to diagnosis occult rib fractures.

Rib fracture diagnosis.

1. Most common injury in blunt force trauma, usually MVA. 2. Fractures of 1st rib indicate SEVERE trauma. 3. SSX: Localized pain, crepitance, pain with inspiration, dyspnea. 4. Rib fracture may cause pneumothorax or hemothorax. 5. Mortality increases with an increased number of ribs fractured. 6. Pain is very severe and may lead to hypoventilation, atelectasis, retained secretions, and pneumonia.

Rib fracture pathophysiology.

1. Rapid mobilization. 2. Respiratory support. 3. Pain management to encourage ventilation. Epidural with bupivicaine controls pain without sedation or impairing cough reflex. 4. Continuous body positioning and oscillation therapy to prevent hypoventilation and atelectasis. This works by promoting redistribution of ventilation and perfusion in various lung segments. 5. Mechanical ventilation to prevent complications of respiratory failure. 6. Incentive spirometry in stable patients. 7. YOUNG and isolated rib fractures without other serious injuries, treatment includes...pain medications, deep breathing, incentive spirometry. 8. Consider admission for ELDERLY and those with serious underlying LUNG DISEASE. They have higher incidence of complications including hypoventilation, atelectasis, and pneumonia.

Rib fractures treatment.

1. Most result from a sternal blow. 2. More common in postmenopausal females, presumed secondary to osteopenia.

Sternal fracture pathophysiology.

1. Occurs most commonly after penetrating trauma. 2. Laceration of air passages, lung parenchyma, or blood vessels. Air enters pulmonary venous system caused by low pulmonary venous pressure which is hypovolemia. It can also be caused by increased airway pressure caused by positive-pressure ventilation or tension pneumothorax. 3. Pulmonary venous air embolizes systemically including coronary and cerebral circulation.

Systemic air embolism pathophysiology.

1. Early recognition is paramount. 2. Supportive care to include IV fluids to maintain euvolemia, supplemental oxygen, chest physiotherapy. 3. If severe, then mechanical ventilation with positive end-expiratory pressure. 4. Admit for monitoring and respiratory support.

Treatment for pulmonary contusion.

1. Pharmacologic management of blood pressure. 2. Prompt surgical or endovascular repair.

Treatment of aortic disruption.

1. PERICARDIOCENTESIS with ultrasound guidance in STABLE PATIENTS is diagnostic and therapeutic. It may not be effective at removing clotted blood. Lots of false negatives and false positives. 2. UNSTABLE PATIENTS with severe shock symptoms need immediate THORACOTOMY.

Treatment of cardiac tamponade.

1. Surgical reduction of hernia and repair of diaphragm is imperative. 2. CAUTION placing chest tube to avoid abdominal injury in patients with torn diaphragm.

Treatment of diaphragmatic hernia.

Treatment depends on location: 1. Most require aggressive surgical management to prevent infection spread to mediastinum and pleural cavities. 2. Some can be managed with drainage, antibiotics, and nutritional support.

Treatment of esophageal dysfunction.

1. Supplemental oxygen. 2. Pain control with morphine or fentanyl. Could use patient controlled administration of opioid. Epidural provides the most complete relief. Do not give NSAIDs if other injuries suspected. 3. Intubation and mechanical ventilation if hypoxic or labored breathing. 4. Early indications for intubation include marked hypoxia, hypercapnea, or inadequate breathing. 5. External chest wall supports reduce vital capacity and may worsen respiratory function. 6. Surgical fixation on when thoracotomy is being performed for other injuries.

Treatment of flail chest.

1. MASSIVE hemothorax indicates *IMMEDIATE tube thoracostomy. DO NOT wait for diagnostic studies.* 2. Smaller hemothoraces can get diagnostic studies first. 3. One or two tube thoracostomies with large bore chest tubes. 4. Autotransfusion with greater than 1 liter blood loss. 5. Surgery for losses greater than 1 to 1.5 liters or loss greater than 200 mL per hour for two to four hours.

Treatment of massive hemothorax.

1. No specific treatment. 2. Treat symptoms and complications as arise. 3. Do not use antidysrhythmic medications prophylactically. 4. Do not use thrombolytics in a trauma patient... 5. Admit elderly, those with history of CAD, significant blunt thoracic trauma, ECG changes, and hypotension.

Treatment of myocardial contusion.

1. Evaluate for shock immediately. 2. Intravenous fluid boluses and blood transfusion, although can cause uncontrolled hemorrhage. 3. If pericardial tamponade identified, then emergent pericardial window or thoracostomy. 4. Tube thoracostomy in all patients with evidence of pneumothorax or hemothorax. 5. Autotransfusion with greater than 1 liter blood loss. 6. Surgery for losses greater than 1 to 1.5 liters or loss greater than 200 mL per hour for two to four hours, or persistent hypotension. 7. Never remove impaled objects in ED. Only remove in OR! 8. GOLD STANDARD TEST: Angiography in hemodynamically stable patients. CT angiography increasingly reliable. 9. Diagnosis to home IF negative CXR, 3 hour observation, then negative repeat CXR. 10. Delayed pneumothorax during observation require tube thoracostomy and admission.

Treatment of penetrating trauma.

1. Symptomatic treatment. 2. Adequate analgesia to encourage deep breathing. 3. Admit patients with cardiovascular complications and patients without adequate analgesia with standard narcotic doses. Also admit those who have limited social support.

Treatment of sternal fracture.

1. Oxygenation is the first line of treatment. 2. Use selective lung ventilation to isolate the affected lung. This will help stop or minimize the flow of gas into circulation. 3. High frequency ventilation has been shown to be effective by allowing decreased ventilatory volumes and pressures. 4. Moribund patient, thoracotomy and clamping of affected lung. 5. Cerebral air embolism treated with hyperbaric oxygen therapy.

Treatment of systemic air embolism.

1. Immediate tube thoracostomy. 2. Alternative if no tube thoracostomy available is a needle thoracostomy with 16 gauge or larger needle in 2nd ICS in midclavicular line. Leave in until tube thoracostomy can be performed. 3. The above treatment will transform a tension to a simple pneumothorax.

Treatment of tension pneumothorax.

1. Endotracheal intubation, preferably over a bronchoscope. Avoid blind intubation. 2. Stable patients should undergo immediate bronchoscopy and operative repair.

Treatment of tracheobronchial injury.

1. No specific therapy, except oxygenation. 2. Hospitalize for observation.

Treatment of traumatic asphyxia.