Which of the following is NOT a ventilatory support technique?

The oxygen delivery system is not classified as a ventilatory support technique because its primary function is to provide supplemental oxygen to patients, rather than to assist or control ventilation. Ventilatory support techniques focus on facilitating the actual process of breathing by ensuring air (or oxygen) is delivered to the lungs and removing carbon dioxide effectively.

On the other hand, techniques such as rescue breaths and the use of big-valve-mask resuscitators or pocket masks actively help in providing breaths to a patient who is unable to breathe adequately on their own. These methods involve actively moving air into the lungs and are critical in emergency situations, especially when a patient is in respiratory distress or failure. Therefore, distinguishing between methods that assist with the physical act of ventilation versus those that simply deliver oxygen is essential in understanding the types of interventions available in emergency medical care.