Air embolism and veins is greater than atmospheric pressure, an air embolus does not often happen when a blood vessel is injured. In the veins above the heart, such as in the head and neck, the venous pressure may be less than atmospheric and an injury may let air in. This is one reason why surgeons must be particularly careful when operating on the brain, and why the head of the bed is tilted down when inserting or removing a central venous catheter from the jugular or subclavian veins. When air enters the veins, it travels to the right side of the
Off-the-Neck Historic District the principal state road leading northward from the village of Castine, which is located at the end of a large peninsula defined by Penobscot Bay on the west and the Bagaduce River on the east. The village proper is located on the Bagaduce Peninsula, which is separated from the larger peninsula by a neck of land between Wadsworth Cove and Hatch Cove. From this neck, SR 166 runs roughly north-by-northeast, paralleling the Bagaduce River up to a junction with Maine State Route 199. SR 166A runs follows a more northerly course, beginning just north of the neck and paralleling the