Mode of Ventilation

Abstract

Mechanical ventilation provides an artificial lung support that completely or partially supports the work carried by respiratory muscles. It is indicated in patients with inadequate respiratory drive, hypoxia, and failure to maintain adequate ventilation. Delivery of air into the lung under positive pressure via an artificial airway (endotracheal tube/tracheostomy tube) is referred to as invasive ventilation. Noninvasive ventilation uses a different interface (mask) and provides support without invasive artificial airway. The mode of mechanical ventilation defines the relationship between the type of breath (spontaneous, assisted, or mandatory) and a group of control variables (volume, pressure) and phase variables (trigger, limit, cycle) that regulate the pattern of breath delivery. Modes of ventilation include assist control, SIMV (synchronized intermittent mandatory ventilation), pressure support, pressure controlled and inverse ratio, APRV (airway pressure release ventilation), and high-frequency ventilation.