Mechanical ventilators have evolved significantly in the last decade. Advances in technology, as well as an increased understanding of the physiology and effects of mechanical ventilation have had a profound impact on ventilator use.

A small number of EMS agencies have introduced automatic transport ventilators as an addition to ALS protocols. These simplified ventilators provide more consistent minute volume than traditional positive pressure ventilation with a bag-valve device. There is also evidence that the use of automatic transport ventilators  may allow paramedics to complete other tasks related to patient care, as they are not directly involved in manual ventilation.