Intrinsic positive end-expiratory pressure at various frequencies of supraglottic jet ventilation in a model of dynamic upper airway obstruction.

Abstract

Supraglottic jet ventilation (JV(S)) with injectors above airway stenoses may result in inadvertent high lung pressures. We designed this study to investigate intrinsic positive end-expiratory pressure (PEEP(i)) during jet ventilation via a distant injector in a model of dynamic upper airway obstruction. Respiratory pressure-time curves were recorded during JV(S) in a tracheal lung model using a pig's trachea and an embolectomy catheter's air-filled balloon to simulate 60 and 80% airway obstruction. JV(S) was performed at various jet frequencies (F(jet) 30 min(-1), 60 min(-1), and 100 min(-1)) and driving pressures (1 bar and 2 bar). JV(S) was associated with generation of PEEP(i), which depended on driving pressure, the degree of obstruction, and on ventilatory frequency. In the presence of a dynamic upper airway obstruction, JV(S) via a distant injector may result in PEEP(i), which cannot be detected when airway pressure is measured in front of the obstruction.