Assisted Ventilation in the ICU: When and to Whom?

Abstract

Mechanical ventilation is a life-saving therapy for most critically ill patients [1]. We can distinguish between: Controlled mechanical ventilation: during controlled mechanical ventilation, the patient has no role in the gas delivery process. Spontaneous respiratory muscle activity needs to be abolished. Assisted mechanical ventilation: assisted mechanical ventilation involves a deep interaction between the patient and the ventilator machine. During this process, the patient’s spontaneous respiratory effort is recognized by the ventilator and assisted with positive pressure applied at the airway open. In this way, the work of breathing (WOB) is shared between the patient and the ventilator. Ventilator’s assistance needs to be synchronized with the patient’s inspiratory effort. Breathing pattern should ideally remain totally under the patient control. Respiratory rate (RR), tidal volume (VT), inspiratory time and inspiratory time/expiratory time ratio (I:E ratio) should be variable on a breath by breath basis.