A positive pressure ventilator delivers gas to the patient through a set of flexible tubes, called a patient circuit. Depending on the ventilator design, this circuit can have one or two main tubes.

The circuit connects the ventilator to an endotracheal tube, tracheostomy tube for invasive ventilation or a noninvasive mask/prong.

For invasive ventilation, an endotracheal tube is inserted through the patient's mouth or nose, or a tracheostomy tube is inserted through an opening made by incision in the neck.

In noninvasive ventilation, the patient circuit connects to a mask covering the mouth and/or nose or nasal prongs.

The tube used for invasive ventilation may have a balloon cuff to provide a seal. The noninvasive mask has a seal around the mouth and nose to prevent the loss of gas/air, ensuring the patient receives appropriate ventilation.

Mechanical ventilation may be used at night, during limited daytime hours, or around the clock, depending on the patient's needs.

Some patients require mechanical ventilation for a short period, such as during recovery from traumatic injury. Others require ventilation long-term, and over time the needs could increase or decrease, depending on the patient's medical status.