328 - Evaluation of Effective Pressure Delivery by Nasal High Frequency Jet Ventilation in a Neonatal Lung Model using NIV+ Software

Publication Number: 328.4744

Rutuja Kibe, Kapi'olani Medical Center for Women and Children, Honolulu, HI, United States; Manoj Biniwale, Cedars Sinai Medical Center, Los Angeles, CA, United States; Rangasamy Ramanathan, Cedars Sinai Guerin Children's, Cedars Sinai Medical Center, Los angeles, CA, United States

Background: Non-invasive ventilation strategies are increasingly used in the neonatal population to mitigate the adverse effects of intubation and invasive ventilation. Nasal High-Frequency Jet Ventilation (nHFJV) is a relatively newer and understudied modality. A limitation of non-invasive ventilation remains the unpredictability and variability of pressures delivered. With the availability of the NIV+ software it has been possible to measure the pressures delivered at the patient interface

Objective: Investigate and quantify effective pressures delivered at non-invasive nasal interface by a novel modality of nHFJV using NIV+ software

Design/Methods: 3D printed nasal models with nasal adapters capable of accommodating differently sized Neotech RAM Cannula® (Neotech, Valencia, CA, USA) were used in the study. The nasal adaptors were connected to neonatal test lungs. The Life Pulse high-frequency jet ventilator (Bunnell Inc., Salt Lake City, UT, USA) was used to provide nHFJV,the Puritan Bennett™ 980 ventilator (Medtronic, Minneapolis, MN, USA) with NIV+ Software provided conventional ventilation. The RAM nasal cannula (Neotech, Valencia, CA, USA) was attached to the LifePort endotracheal tube adapter (Bunnell Inc.) to deliver jet breaths noninvasively. Each size of the Ram cannula was tested for different combinations of jet rate (240-360) and inspiratory time (IT, 0.02 – 0.03 sec) with basal Non-invasive positive pressure (NIPPV) settings (Peak inspiratory pressure PIP 25/30/35, Positive end-expiratory pressure PEEP 6/8/10, rate 40, IT 0.5 sec). Statistical analysis was performed using IBM SPSS Statistics for Windows

Results: 432 data points were analyzed across all sizes of the cannula. PIP at interface (PIPif) and PEEP at interface (PEEPif) were lower than set pressures by mean of 4.09 and 0.4 cm H2O respectively (P < 0.01) when using nHFJV. During testing pressure delivery with and without jet (i.e. NIPPV only) there was no difference in PIPif, however there was consistently higher PEEPif delivered with NHFJV (P < 0.01). Mean PEEP with jet was 0.41 cm H2O lower than set on ventilator whereas PEEP without added jet (NIPPV only) read significantly lower by 0.93 cm H2O (p value < 0.01) Significantly less leak (P < 0.01) was noted with NHFJV (1.1 LPM) as compared to NIPPV (1.77 LPM) alone

Conclusion(s): This is the first bench study to measure the delivered pressures on nHFJV. NHFJV could potentially deliver a higher mean airway pressure as compared to NIPPV alone, which could aid bedside clinical decision-making, e.g use as a post-extubation step-down mode or escalation mode prior to intubation

Fig1
Model

graph1
PIPif and PEEPif comparison with and without nHFJV

graph2
Comparison of leak with and without addition of NHFJV