PT - JOURNAL ARTICLE AU - S. Nava AU - A. Carlucci AU - P. Ceriana TI - Patient–ventilator interaction during noninvasive ventilation: practical assessment and theoretical basis AID - 10.1183/18106838.0504.322 DP - 2009 Jun 01 TA - Breathe PG - 322--333 VI - 5 IP - 4 4099 - http://breathe.ersjournals.com/content/5/4/322.short 4100 - http://breathe.ersjournals.com/content/5/4/322.full SO - breathe2009 Jun 01; 5 AB - Summary Synchrony refers to the agreement between the patient's own (neural) and the ventilator's (mechanical) inspiratory and expiratory time. Noninvasive ventilation (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 that affect patient–ventilator mismatching. This review will focus on NIV and on the main forms of asynchrony and mismatching, their causes and methods to eventually identify these problems from the flow and pressure signals.