Harms of unintentional leaks during volume targeted pressure support ventilation

Most of the studied ventilators with a single-limb circuit with intentional leak correctly estimate the expiratory VT and therefore successfully maintain the preset minimal VT during unintentional leaks, in contrast to most of the studied ventilators with a double-circuit, which paradoxically are not able to directly measure expiratory VT. Importantly, the VT-PSV mode, when used with most ventilators with expiratory valve or double-circuit, can paradoxically exacerbate the VT drop during unintentional leaks.