Harms of unintentional leaks during volume targeted pressure support ventilation.

Sonia Khirani (1) , Bruno Louis (2) , Karl Leroux (3) , Vincent Delord (4) , Brigitte Fauroux (1) , Frédéric Lofaso (5)

1 IMRB - Institut Mondor de Recherche Biomédicale
2 INSERM U955, équipe 13
3 ADEP ASSISTANCE
4 CHU Trousseau [APHP]
5 INSERM U955, équipe 13

BACKGROUND: Volume targeted pressure support ventilation (VT-PSV) is a hybrid mode increasingly used to maintain a minimal tidal volume (VT) by automatically adjusting the level of inspiratory pressure. The objective of the study was to determine the ability of home ventilators to maintain the preset minimal VT during unintentional leaks in a VT-PSV mode. METHODS: Seven ventilators were tested on a lung bench with different circuit configurations and with different levels of unintentional leaks. Unintentional leaks were generated using calibrated holes. RESULTS: All the studied ventilators with a single-limb circuit with intentional leak (n = 5) were able to maintain the minimal preset VT during unintentional leaks. One ventilator overcompensated VT during unintentional leaks of high intensity. In contrast, all studied ventilators with a single circuit with an expiratory valve (n = 2) or a double-circuit (n = 3) but one failed to maintain the minimal VT during unintentional leaks. Unintentional leaks generated a decrease in inspiratory pressure, which was responsible for the fall in VT. CONCLUSIONS: 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.

Mots clés: Home ventilators; Pressure support; Unintentional leaks; Volume targeted; Hybrid mode; Ventilatory circuit

Domaines: Biochimie, Biologie Moléculaire

Sonia Khirani, Bruno Louis, Karl Leroux, Vincent Delord, Brigitte Fauroux, et al.. Harms of unintentional leaks during volume targeted pressure support ventilation.: Efficiency of Targeted Volume Mode. Respiratory Medicine, 2013, 107 (7), pp.1021-9. ⟨10.1016/j.rmed.2013.03.013⟩. ⟨inserm-00854227⟩