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Blunt chest trauma is a common finding in all trauma patients. The injuries that result are principally a function of the magnitude of force, and the location and direction over which it is applied. Consequently, a history of the injury should always be sought as it will point towards the likely diagnostic alternatives. Penetrating trauma on the other hand produces a more limited range of problems, principally haemothorax, pneumothorax and rarely haemopericardium. Surgery is seldom indicated in blunt chest trauma. The major principle is to support the patient while injuries heal. ASSESSMENT If in doubt about the airway: Intubate. See notes on air embolism in penetrating chest trauma. If in doubt about the chest movement: Ventilate. Resuscitate and assess simultaneously. HISTORY From patient and witnesses about seat belts, steering wheel if driver, speed, nature of collision. In industrial accidents: what fell on the patient? How long was the patient crushed? EXAMINATION Look for effective and equal chest wall movement paradoxical movement, respiratory rate, the ability of the patient to give a history, breath sounds, deviated mediastinum and fullness of the neck veins, subcutaneous emphysema and rib tenderness. Chest injuries are often associated with other injuries so a high index of suspicion should be maintained. CHEST X-RAY An erect chest film is the single most important investigation and should be called for early to aid assessment. (Visit our trauma x-ray collection section for examples) Look for:
A subsequent chest X-Ray should be performed if there are significant
chest injuries as the initial X-Ray often understates the extent of damage,
particularly lung contusion. POSSIBLE INJURIES PNEUMOTHORACES Open Pneumothorax (sucking chest wound) ->Cover immediately with rolled vaseline gauze from the intercostal trolley. Insert an intercostal tube. Pneumothorax ->Insert an intercostal tube if the patient is to undergo anaesthesia, IPPV, or if the pneumothorax occupies more than 20% of the lung field. Patients with underlying pulmonary disease may tolerate small pneumothoraces poorly. Tension Pneumothorax ->If the patient is severely compromised, a 12G cannula may be inserted into the 2nd intercostal space, mid clavicular line. Insert an intercostal catheter without CXR if unstable Otherwise perform a Chest X-ray (if the patient is stable, it is probably not a tension pneumothorax) TRACHEOBRONCHIAL TREE RUPTURE Relatively rare. Marked by haemoptysis, extra-alveolar air and persistent pneumothorax. Control of ventilation and bronchoscopy/surgery are usually indicated. HAEMOPNEUMOTHORAX This bleeding usually stops. Any significant haemothorax (visible on chest X-ray) should be drained via an intercostal tube. Blood loss is accurately reflected by the loss from patent intercostal tube. Continued bleeding often indicates arterial loss from an intercostal artery rather than from the low pressure pulmonary circuit. Thoracotomy should be considered when total loss is more than 1500ml of blood, or if blood drainage exceeds 300ml/hr. CHEST DRAINAGE An intercostal catheter, 32G or larger, with the trocar removed, should be inserted in the fifth or sixth intercostal space just anterior to the mid-axillary line. Liberal use of local anaesthetic (to the pleura, muscle and skin) is followed by a skin incision of 1.5cm. Blunt dissection is then performed down to, then through the pleura, and the tube is inserted by directing it posteriorly and superiorly towards the apex. Avoid purse string sutures - use simple mattress sutures. Secure the tube to the side of the body with elastoplast. Place the underwater seal below the bed. The tube should only be clamped for a good reason and with extreme caution to prevent tension pneumothorax. If there is free bleeding, milk the tubes to avoid clotting. Suction (20cm water) is often necessary to drain blood and air. LUNG CONTUSION Lung contusion is usually associated with rib fractures and flail segments and is always associated with hypoxia. Administer oxygen. Continual reassessment is required as oxygenation and ventilation usually deteriorates over the initial four hours. FLAIL CHEST Flail chest not only makes ventilation less efficient but often is associated with underlying contusion and hypoxia. The cornerstone of consenative management is complete pain relief with narcotics and thoracic epidurals. Mechanical ventilation is reserved for those patients who do not respond to conservative therapy. DIAPHRAGMATIC RUPTURE Difficult to diagnose and often missed. Mostly seen on the left side. Suspect when there is diminished air entry, bowel sounds in the chest, mediastinal shift. Suspect on chest X-Ray, but beware that this can be missed on CT as well. The best chance for diagnosis lies in a high index of suspicion. Requires surgical exploration and repair. MULTIPLE RIB FRACTURES May occur without flail segment but should be treated as a flail due to the high incidence of contusion. Beware of this injury in the elderly - respiratory failure is almost inevitable and anticipatory intubation and ventilation should be performed before it supenenes. FRACTURED STERNUM Usually extremely painful and associated with a steering wheel injury. Patients are admitted to monitor for the rare complications of cardiac arrhythmia's and heart failure, secondary to myocardial contusion. A 12-lead ECG must be examined. INJURIES TO MEDIASTINAL STRUCTURES These injuries associated with violent high speed decelerating injuries. Most significant injuries are immediately fatal. MYOCARDIAL CONTUSION Associated with anterior chest wall injury, (eg fractured sternum) and often caused by impact with steering wheel. Usually responds to conservative measures and rarely associated with significant heart failure or arrhythmias. PENETRATING CARDIAC INJURIES Consider the diagnosis with a suspicious chest wound in a moribund patient or one who remains hypotenshe in spite of fluid therapy. The former should be taken to theatre immediately to relieve tamponade and suture any myocardial wounds, and the latter should be transported urgently to a cardiothoracic unit. PERICARDIAL TAMPONADE Presents as shock with distending neck veins. Should be differentiated from tension pneumothorax, myocardial contusion or infarction. Requires emergency thoracotomy (see below). GREAT VESSEL INJURY Most patients fail to reach hospital. Always suspect when patient complains of chest or interscapular pain following high speed collision. If the chest X-ray shows a widened mediastinum, the patient requires urgent angiography. TRAUMATIC AIR EMBOLISM Suspect in penetrating chest wounds where there is sudden deterioration in cardiac output after intubation, neurological signs in the absence of a head injury, haemoptysis or froth in the blood gas syringe. EMERGENCY ROOM THORACOTOMY This procedure is a desperate measure performed to try and save profoundly shocked patients with massive continuing blood loss, or with a severe pump problem such as pericardial tamponade or air embolism. INDICATIONS 1. The surgeon should have had previous thoracic surgical experience, even if only limited. 2. The patient should have had some vital signs in the previous 15 minutes.
3. Patients who arrive with penetrating trauma and recent cardiac arrest should undergo immediate thoracotomy; a patient whose blood pressure does not rise to above 60mm Hg within 5 to 10 minutes despite maximal supportive measures should have Emergency Room thoracotomy at that stage. PROCEDURE The patient is supine with the arm raised above the head. Ipsilateral thoracotomy is performed with unilateral penetrating injuries (Beware of right atrial injuries from a right parasternal stab). Left thoracotomies are preferred for access to the heart. Median sternotomy does not provide as good access as bilateral thoracotomies, and we are equipped for thoracotomy rather than sternotomy. Instruments are available for clamping lung hila and other major structures, and for suturing cardiac wounds:
DISCONTINUATION OF RESUSCITATION Prolonged resuscitation is futile and heroic measures should stop if:
EXPECTED RESULTS Occasional saves are possible, but are of the order of 8-10%, of whom half will have serious neurological deficit. Without this treatment of course, none of these patients will survive. To select the best survivors, those with blunt trauma, multiple cavity trauma, or no vital signs at the scene should all be excluded from attempts at this form of treatment.
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