Low-frequency jet ventilation as a form of pressure-controlled ventilation: a mechanistic study using simulated lung models

Abstract Jet ventilation requires an open airway, making accurate monitoring of tidal volume ( V T ) and airway pressure (Paw) challenging. Whether low frequency jet ventilation (LFJV) is comparable to conventional pressure-controlled ventilation (PCV) in terms of V T , pressure rise time ( T slope ), and pressure rise slope (Ramp) remains unclear due to limited evidence. Using two simulated lung models under open airway conditions, LFJV and PCV were compared. The LFJV group was ventilated with a driving pressure (DP) of 0.6–1.6 bar, frequency of 10–30 bpm, and I: E ratio of 1:1. V T , peak inspiratory pressure (PIP), and machine delivered flow ( Flow inject ) were measured, with Paw waveforms recorded. In the PCV group, PIP values from the LFJV group were used as the target inspiratory pressure ( P insp ), with matching frequency and I: E ratio, while using the default inspiratory flow ( Flow insp ) of 30 L/min. T slope and Ramp were derived from Paw waveforms in both groups. V T did not differ significantly between the two groups (mean difference: − 43.03 mL [95% CI: − 123.58 to 37.53], P = 0.2925). Machine-delivered flow ( Flow inject in LFJV vs. Flow insp in PCV) also showed no significant difference (mean difference: 0.6 L/min [95% CI: − 7.25 to 8.45], P = 0.8520). The T slope was significantly shorter in the LFJV group than in the PCV group (mean difference: − 0.58 s [95% CI: − 0.96 to − 0.20], P = 0.0066), and the Ramp was markedly steeper in LFJV (mean difference: 23.7 cmH₂O/s [95% CI: 18.25 to 29.16], P < 0.0001). Low-frequency jet ventilation can be characterized as a pressure-controlled mode under the conditions tested, whose pressurization kinetics are directly governed by driving pressure. The preserved acceleration in pressure rise, even at matched machine-delivered flows, highlights the unique role of Venturi-augmented flow in LFJV’s gas delivery dynamics.