Patient-ventilator Interaction During NIV With Helmet: a Comparison Between PSV and the New NIV NPS Software

Study Overview
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Brief Summary
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The goal of this clinical trial is to evaluate if neural pressure support ventilation is able to improve patient-ventilator synchrony, in ICU patients undergoing non-invasive ventilation (NIV). The main question it aims to answer is: • Is neural pressure support ventilation better than the pressure support ventilation with respect to patient-ventilator synchrony during helmet NIV? Researchers will compare neural pressure support ventilation versus pressure support ventilation (Gold standard assisted mode in Europe) to see if the new mode improve patient-ventilator synchrony.

Detailed Description
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Non-Invasive Ventilation (NIV) has found many different uses in clinical settings, shortening intubation times and preventing orotracheal intubation. NIV success is highly affected by patient comfort and patient-ventilator synchrony. The helmet is one of the most comfortable interfaces, even if synchrony is low due to dead space. The use of Neurally Adjusted Ventilatory Assist (NAVA), in which the Electrical Activity of the Diaphragm (EAdi) drives the ventilator, has shown improvement in comfort and synchrony but still some limitation with helmet, due to the long pressurization time. Pressure-Support Ventilation (PSV) is still the most used and diffused assisted mode in Europe due to its simplicity and effectiveness in helmet-NIV. The aim of this study is to test a new ventilation software called Neural Pressure Support Ventilation (nPSV), which merges the rapid pressurization of PSV along with the EAdi trigger, onto a population of 24 critical care patients ventilated with a helmet NIV.

Official Title
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Patient-ventilator Interaction During NIV With Helmet: a Comparison Between PSV and the New NIV NPS Software

Conditions
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Respiratory Failure, Mechanical Ventilation Complication

Intervention / Treatment
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* Device: nPSV and PSV


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Adult patients (>18aa) Non Invasive Ventilation with helmet NG tubing for clinical use in position Invasive arterial monitoring for clinical use in position Exclusion Criteria: Unable to express consent Expected NIV < 24hrs Gastric-esophageal surgery in the preceding 12 months Upper-GI bleeding in the last 30 days History of esophageal varices Recent trauma or facial surgery Haemodinamic instability even a after liquid infusion (need of at least dopamine >5 γ/kg/min or norephinephrine >0.1 γ/kg min to obtain systolic pressure >90 mmHg) Core temperature >30C° Coagulation disorders (INR > 1.5 and/or aPTT >44 sec)

Ages Eligible for Study
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Minimum Age: 18 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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No

Study Plan
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How is the study designed?
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Design Details

Primary Purpose: Treatment
Allocation: Randomized
Intervention Model: Crossover Assignment
Interventional Model Description: Patients will be ventilated in nPSV or PSV (according to randomization) and then, after an initial period of ventilation, they will be ventilated with the other technique. Ventilation then will be optimized by an expert and the two modes of ventilation will be repeated in succession.
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: nPSV first<br>Patients will follow the pattern: nPSV -> PSV -> nPSVo -> PSVo | Device: nPSV and PSV<br>* Ventilation with neurally adjusted modes or pressure support modes<br>|
| Experimental: PSV first<br>Patients will follow the pattern: PSV -> nPSV -> PSVo -> nPSVo | Device: nPSV and PSV<br>* Ventilation with neurally adjusted modes or pressure support modes<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Improvement of synchrony in nPSV v.s PSV | Synchrony time [Timesych]: time frame during which both the ventilator and the neural patient inspiratory time are in the inspiratory phase (s) | last 2 minutes over 30 minutes registration | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Respiratory pattern in nPSV vs PSV | Tidal Volume (ml) | last 2 minutes over 30 minutes registration | 
| Respiratory pattern in nPSV vs PSV | Minute Volume Ventilation (L) | last 2 minutes over 30 minutes registration | 
| Respiratory pattern in nPSV vs PSV | Respiratory Rate (Breath per minute) | last 2 minutes over 30 minutes registration | 
| Respiratory pattern in nPSV vs PSV | Inspiratory Time [Ti] (s) | last 2 minutes over 30 minutes registration | 
| Respiratory pattern in nPSV vs PSV | Neural Inspiratory Time [Tineu] (s) | last 2 minutes over 30 minutes registration | 
| Patient Ventilator Synchrony in nPSV vs PSV | Inspiratory Neural-Ventilator Coupling [NCVi] (Percentage) | last 2 minutes over 30 minutes registration | 
| Respiratory pattern in nPSV vs PSV | Peak of Electrical Activity of the diaphragm [EAdi peak] (mcV) | last 2 minutes over 30 minutes registration | 
| Patient Ventilator Synchrony in nPSV vs PSV | Asynchrony Index (AI): ratio between the number of ineffective efforts, auto-triggers and double triggers and the neural respiratory rate plus auto-triggers (percentage) | last 2 minutes over 30 minutes registration | 

 Terms related to the study
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Keywords Provided by Centre Hospitalier Valida
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Mechanical Ventilation, Non Invasive Ventilation, Weaning, Neurally Adjusted Ventilator Assist