In general aviation, a cannula refers to a piece of plastic tubing that runs under the nose and is used to administer oxygen in non-pressurized aircraft flying 10,000 feet above sea level. In synthetic chemistry, a cannula refers to a piece of stainless steel or plastic tubing used to transfer liquids or gases from one vessel to another without exposure to air. See more at Cannula transfer. See also Catheter Hypodermic needle Cannulated cow Cannulated bar References External links Decannulation, Cincinnati Children's Hospital Medical Center Medical equipment