Patient–ventilator interaction during noninvasive ventilation: practical assessment and theoretical basis

Abstract

Synchrony refers to the agreement between the patient's own (neural) and the ventilator's (mechanical) inspiratory and expiratory time. Noninvasive (NIV) is a semi-open system, which means air leaks are common. This greatly affects patient synchrony. In addition to air leaks there are other factors which affect patient-ventilator mismatching. This review will focus on NIV and on the main forms of asychrony and mismatching, their causes and methods to eventually identify these problems from the flow and pressure problems.