An 18-year-old man shot once in the left chest has a blood pressure of 80/50 mm. Hg, a heart rate of 130 beats per minute, and distended neck veins. Immediate treatment might include:

A. Administration of one liter of Ringer's lactate solution.

C. Needle decompression of the left chest in the second intercostal space.

DISCUSSION: The finding of distended neck veins in conjunction with hypotension should suggest tension pneumothorax or pericardial tamponade. Absent ipsilateral breath sounds and a trachea deviated to the contralateral side may provide additional evidence for a tension pneumothorax, the immediate treatment of which is needle decompression of the chest in the second or third intercostal space in the midclavicular line. Pericardial tamponade may initially respond to volume administration by enhancing preload. Pericardiocentesis may need to be performed emergently if hemodynamic instability persists after an initial fluid bolus when signs of compressive cardiogenic shock are present. Subxiphoid pericardiotomy should be performed only in the operating room by experienced persons who are trained to deal with penetrating cardiac injuries. There is no role for aortic cross-clamping in this scenario of cardiogenic shock.