A 25-year-old man is brought to the emergency department due to a stab wound to the chest. The patient was returning to his parked car when he was mugged. He tried to resist, but the assailant stabbed him once in the left chest with a switchblade. During transport, the patient became unresponsive and required intubation. He also received 2 L of normal saline. Upon arrival, blood pressure is 80/42 mm Hg and pulse is 132/min. Pulse oximetry is 98% on 60% oxygen. Weight is 80 kg (176.4 lb) and height is 177.5 cm (5 ft 9 in). On physical examination, there is a fist-sized blood stain on the patient's shirt and a 3-cm linear wound in the left fifth intercostal space at the midaxillary line, with dried blood and no active external hemorrhage. Breath sounds are diminished in the left lung and normal in the right lung. Heart sounds are normal. The jugular veins are flat. The abdomen is nondistended and soft to palpation. Focused assessment with sonography for trauma (FAST) reveals left-sided intrathoracic free fluid. A left-sided chest tube is placed with immediate output of 2,000 mL of blood. Which of the following is the best next step in management of this patient?

Question

A 25-year-old man is brought to the emergency department due to a stab wound to the chest.  The patient was returning to his parked car when he was mugged.  He tried to resist, but the assailant stabbed him once in the left chest with a switchblade.  During transport, the patient became unresponsive and required intubation.  He also received 2 L of normal saline.  Upon arrival, blood pressure is 80/42 mm Hg and pulse is 132/min.  Pulse oximetry is 98% on 60% oxygen.  Weight is 80 kg (176.4 lb) and height is 177.5 cm (5 ft 9 in).  On physical examination, there is a fist-sized blood stain on the patient's shirt and a 3-cm linear wound in the left fifth intercostal space at the midaxillary line, with dried blood and no active external hemorrhage.  Breath sounds are diminished in the left lung and normal in the right lung.  Heart sounds are normal.  The jugular veins are flat.  The abdomen is nondistended and soft to palpation.  Focused assessment with sonography for trauma (FAST) reveals left-sided intrathoracic free fluid.  A left-sided chest tube is placed with immediate output of 2,000 mL of blood.  Which of the following is the best next step in management of this patient?

Quizplus · Accepted Answer

Explanation: Hypovolemic shock (ie, severe hypotension, tachycardia, flat neck veins) in the setting of penetrating chest trauma (ie, stab to chest) is attributed to hemorrhage until proven otherwise; trauma primary survey should seek to identify sources of bleeding. In this patient, diminished breath sounds on the side of the stab wound led to tube thoracostomy with significant bloody output, thereby identifying the hemorrhage source as intrathoracic. A small external wound can conceal extensive internal injury. Central penetrating wounds inside "the box"-delineated superiorly by the clavicles, inferiorly by the costal margins, and laterally by the nipples-are particularly dangerous because of the underlying heart and mediastinal structures. However, even lateral wounds (eg, this patient's 3-cm lateral wound) can cause significant injury, including massive hemothorax (>1,500 mL) from laceration of underlying lung parenchyma or intercostal vessels. Although tube thoracostomy is often sufficient to manage hemothorax, some patients (up to 15%) require emergent thoracotomy for extreme bleeding, including those with: Initial bloody output >1,500 mL (as in this patient) Persistent hemorrhage: >200 mL/hr for >2 hours, or continuous need for blood transfusion to maintain hemodynamic stability (Choice A) Clamping the chest tube is not recommended; blocking the outflow of blood does not staunch the bleeding (the capacity of the hemithorax is too great), and accumulated intrathoracic blood negatively impacts respiratory mechanics (eg, restricted lung expansion). (Choice B) A contrast-enhanced CT scan can assist in identifying a bleeding source (via visualization of contrast extravasation); however, it is only appropriate for hemodynamically stable patients. This patient is unstable (ie, hypotensive despite fluids), and his massive chest tube output warrants emergent surgical intervention. (Choices D and E) Cardiac tamponade (ie, hemopericardium) is a life-threatening possibility in penetrating thoracic trauma; it can be visualized on transthoracic echocardiography and treated with pericardiocentesis. Although acute tamponade can cause severe hypotension and tachycardia, it classically causes elevated jugular venous pressure with distended (rather than flat) neck veins. (Choice F) Vasopressors are appropriate for patients with severe peripheral vasodilatation due to distributive (eg, septic, neurogenic) shock. Patients (such as this one) with shock due to blood loss (ie, hemorrhagic shock) should receive volume resuscitation with blood transfusion while awaiting definitive management of the hemorrhage (eg, surgical intervention). Vasopressor administration without appropriate resuscitation can worsen tissue perfusion. Educational objective: Penetrating trauma accompanied by shock (eg, severe hypotension) is attributed to hemorrhage until proven otherwise. Intrathoracic hemorrhage can cause massive hemothorax (>1,500 mL), which requires emergent thoracotomy to prevent exsanguination. References: Practice management guidelines for management of hemothorax and occult pneumothorax. (http://www.ncbi.nlm.nih.gov/pubmed/21307755) Hemothorax: etiology, diagnosis, and management. (http://www.ncbi.nlm.nih.gov/pubmed/23206720)

A 25-Year-Old Man Is Brought to the Emergency Department Due