An 8-year-old male was stabbed in the chest with a knife. You observe a half-inch laceration an inch lateral to the sternum at the third intercostal space. You do not see any active bleeding, and his neck veins are distended. His lungs are clear to auscultation. His capillary refill is three seconds, and his skin is pale and cool. You should suspect:
1) Pneumothorax
2) Hemothorax
3) Cardiac tamponade
4) Tension pneumothorax