A 24-year-old man presents to the emergency room after a motor vehicle collision. He was the driver in a head-on collision and was not wearing a seatbelt. The patient is acutely intoxicated and is attempting to attack the nurses. Soon after presentation, he is sedated, paralyzed, and intubated. His medical history is unknown. His temperature is 97.6°F (36.4°C), blood pressure is 74/34 mmHg, pulse is 180/min, respirations are 32/min, and oxygen saturation is 98% on room air. Physical exam is notable for jugular venous distension. An electrocardiogram (ECG) is performed as seen in Figure A. Which of the following is the most appropriate next step in management?
Needle thoracostomy
Pericardial window
Tube thoracostomy
Pericardiocentesis
Pericardiocentesis
This patient is presenting after trauma with hypotension, tachycardia, jugular venous distension, and electrical alternans on ECG, which is concerning for cardiac tamponade. The most important initial step in management is pericardiocentesis.

Cardiac tamponade can occur after trauma, infections, or malignancy. It can occur if there is an accumulation of fluid in the pericardial sac with inadequate time for the pericardial sac to stretch and for the heart to adapt to the compression that causes diastolic dysfunction. Patients will present with hypotension, tachycardia, jugular venous distension, muffled heart sounds, and pulsus paradoxus (blood pressure drop > 10 mmHg with inspiration). The diagnosis can be supported with ultrasonography (in the clinical setting a point of care ultrasound will often be performed first); however, the initial step in management is a pericardiocentesis which will stabilize the patient. Subsequent management requires the placement of a pericardial drain or window, as well as treatment of the underlying cause.

Prabhakar et al. discuss pericardial decompression syndrome, an infrequent complication of pericardiocentesis. The authors find that pericardial decompression syndrome presents with paradoxical hemodynamic instability and/or pulmonary edema following pericardiocentesis, especially in patients with underlying myocardial dysfunction. The authors recommend careful monitoring of patients after pericardiocentesis for the development of this complication.

Figure/Illustration A is an ECG demonstrating electrical alternans. Note the alternating large QRS complexes (blue arrows) and small QRS complexes (green arrows) which are suggestive of the heart swinging in a fluid-filled pericardium.

Incorrect Answers:
Answers 1 & 5: Needle thoracostomy followed by tube thoracostomy is the appropriate management of a tension pneumothorax. A tension pneumothorax would also present with hypotension, tachycardia, and jugular venous distension; however, it would not present with muffled heart sounds and electrical alternans on ECG. On exam, there would be an absence of unilateral breath sounds and the presence of tracheal deviation.

Answer B: Packed red blood cells are appropriate management of a hypotensive and tachycardic trauma patient when it is suspected that their unstable vitals are secondary to hemorrhage. In this patient, there is conclusive evidence (jugular venous distension and electrical alternans) that this patient has cardiac tamponade.

Answer C: Pericardial window is the appropriate long-term treatment of recurrent pericardial effusions as it allows for a permanent conduit for the drainage of fluid. An acutely unstable patient should first be stabilized with a pericardiocentesis before going to the operating room for this procedure.

Bullet Summary:
The most important initial step in the management of cardiac tamponade in a hemodynamically unstable patient is pericardiocentesis.