The parts of an ambu bag are a self-inflating silicone bag, tubing, two one-way valves and an adapter. The bag can be filled with room air or oxygen through a one-way valve. The bag is then compressed to force the air or oxygen through the other one-way valve, through an adapter that connects to either a breathing tube or face mask and into the patient 's lungs.
Some ambu bags come with an added reservoir and tubing to monitor the pressure of the oxygen before reaching the patient. Ambu bags are meant to assist in breathing and are often used in conjunction with chest compressions, as they are more successful in getting oxygen to the brain than mouth-to-mouth resuscitation. It requires two people to use an ambu bag: one to hold the mask securely over the patient's mouth so air doesn't escape, and one to squeeze the bag.
Ambu bags come in different sizes and can be used for infants, children and adults. The bag was invented in 1953 by a Danish engineer, Dr. Holger Hesse, and an anesthesiologist, Henning Ruben. As of 2014, the company they started is still making ambu bags, which are the most widely used manual resuscitators.