Final answer:
When air is forced into a patient's lungs using an external device, it is referred to as artificial respiration or assisted ventilation, a critical technique in medical emergencies or surgeries.
Step-by-step explanation:
When air is forced into a patient's lungs, such as with a bag valve mask (BVM) or mechanical ventilation, the technique is known as artificial respiration or assisted ventilation. This is a part of the broader process of pulmonary ventilation, which involves inspiration and expiration driven by pressure differences. In particular, assisted ventilation can be necessary when a patient is unable to breathe on their own due to illness, injury, or anesthesia. Applying force on a balloon connected to the patient, to generate a specific gauge pressure, exemplifies how mechanical force can be used to aid or stimulate breathing in a medical context.