a better seal is achieved, the jaw thrust maneuver is more easily maintained and the patient's lungs can be ventilated more effectively.Demand Valve DeviceThe demand valve device is also commonly referred to as the "manually triggered oxygen powered breathing device." This device will transport 100 percent oxygen to a patient at its maximum flow rate (40L per minute). This system consists of a high-pressure tube, which connects to an oxygen supply. A push lever or button easily activates the valve causing it to open and thus, supplying oxygen to the patient.Automatic VentilatorsDue to technological advances, compact mechanical ventilators are now available for pre-hospital use. Mechanical ventilators provide a number of advantages over other types of ventilatory support discussed previously. Mechanical ventilation is lightweight and compact which makes it convenient and very easy to use while transporting the patient to the hospital. Secondly, they are an improvement over the bag-valve device in maintaining minute volume. The mechanical ventilation system is also able to endure extreme temperatures. Temperatures ranging from 30 degrees Fahrenheit to 125 degrees Fahrenheit. Another advantage of mechanical ventilation is that most systems are typically equipped with both an adjustable ventilatory rate and tidal volume. This will allow the machine to function intermittently, reverting to controlled mechanical ventilation in patients who are not breathing. Some are contain a "pop-off" valve that prevents pressure-related injuries. A "pop-off" valve can prove to be detrimental in situations where the patient is suffering from a pulmonary contusion, bronchospasm, cardiogenic pulmonary edema, adult respiratory distress syndrome or disorders in which high levels of pressure in the airway must be surmounted. In closing, there are several effective methods of supplying respiratory support to patients. Although, the mechanical vent...
