Physiology of Helmet vs. Facemask Noninvasive Ventilation

Physiological Effects of Helmet vs. Facemask Noninvasive Ventilation in Acute Hypoxemic Respiratory Failure

The optimal noninvasive management of acute hypoxemic respiratory failure is debated. Helmet noninvasive ventilation may be more effective than facemask noninvasive ventilation for these patients. Putatitve benefits of helmet use are the possibility to apply significantly higher positive end-expiratory pressure without air leaks and with good patient's comfort.

In this randomized crossover study, the investigators will assess the physiological effects of helmet compared to facemask noninvasive ventilation, with the latter applied with different ventilator settings (similar to or different from helmet settings).

Study Overview

• Status: Completed
• Conditions: Acute Hypoxemic Respiratory Failure
• Intervention / Treatment: Device: Noninvasive ventilation

• Study Type: Interventional
• Enrollment (Actual): 20
• Phase: Not Applicable

Contacts and Locations

Study Locations

• Italy
  • Rome, Italy
    • Fondazione Policlinico Universitaro A. Gemelli IRCCS

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

• Acute hypoxemic respiratory failure and PaO2/FiO2<200 mmHg
• PaCO2<45 mmHg
• Respiratory failure not caused by exacerbation of chronic pulmonary disease, cardiac failure or fluid overload

Exclusion Criteria:

• Pregnancy
• Contraindication to helmet or facemask noninvasive ventilation
• Contraindication to esophageal manometry
• Contraindication to electrical-impedance tomography monitoring
• Recent surgery involving the abdomen or the thorax
• Pneumothorax or documented barotrauma

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Crossover Assignment
• Masking: None (Open Label)

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Helmet noninvasive ventilation; 1-hour treatment with helmet noninvasive ventilation (PEEP 12 cmH2O + pressure support 10 cmH2O).	Device: Noninvasive ventilation; noninvasive ventilation
Active Comparator: Facemask noninvasive ventilation (facemask settings); 1-hour treatment with facemask noninvasive ventilation (PEEP 5 cmH2O + pressure support 10 cmH2O).	Device: Noninvasive ventilation; noninvasive ventilation
Active Comparator: Facemask noninvasive ventilation (helmet settings); 1-hour treatment with facemask noninvasive ventilation (PEEP 12 cmH2O + pressure support 10 cmH2O).	Device: Noninvasive ventilation; noninvasive ventilation

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Inspiratory effort	negative deflection in esophageal pressure	1 hour
End-expiratory lung impedance	Electrical-impedance derived end-expiratory lung volume	1 hour

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Respiratory rate	Respiratory rate per minute	1 hour
Tidal volume	Electrical-impedance derived tidal volume size	1 hour
Work of breathing	Esophageal pressure simplified pressure-time product	1 hour
Dynamic transpulmonary driving pressure	Tidal change in transpulmonary pressure	1 hour
Compliance	Ratio of tidal volume to transpulmonary driving pressure	1 hour
Dyspnea	Dyspnea rated through a visual analog scale (ranging from 0 to 10, with representing most severe dyspnea) adapted for critically ill patients	1 hour
Discomfort	Device-related discomfort (ranging from 0 to 10, with representing most severe dyspnea) rated through a visual analog scale adapted for critically ill patients	1 hour
Oxygenation	PaO2/FiO2 ratio	1 hour
Pendelluft extent	Pendelluft extent, expressed in % of the total tidal volume	1 hour
Corrected minute ventilation	The product of tidal volume and respiratory rate, normalized to PaCO2. This value is expressed in Arbitrary units per minute divided by mmHg and is a proxy of dead space	1 hour
Arteria Carbon dioxide tension	PaCO2	1 hour
Tidal volume distribution	Tidal volume distribution, assessed with electrical impedance tomography in 4 regions of interest (ventral, mid-ventral, mid-dorsal, dorsal)	1 hour

Collaborators and Investigators

• Sponsor: Fondazione Policlinico Universitario Agostino Gemelli IRCCS
• Investigators: Principal Investigator: Domenico L. Grieco, MD, Fondazione Policlinico A. Gemelli IRCCS

Study record dates

Study Major Dates

• Study Start (Actual): January 19, 2024
• Primary Completion (Actual): July 31, 2025
• Study Completion (Actual): September 15, 2025

Study Registration Dates

• First Submitted: January 2, 2024
• First Submitted That Met QC Criteria: January 15, 2024
• First Posted (Actual): January 18, 2024

Study Record Updates

• Last Update Posted (Estimated): September 30, 2025
• Last Update Submitted That Met QC Criteria: September 29, 2025
• Last Verified: September 1, 2025

More Information

Terms related to this study

• Additional Relevant MeSH Terms: Respiratory Tract Diseases; Respiration Disorders; Respiratory Insufficiency; Therapeutics; Airway Management; Respiratory Therapy; Respiration, Artificial; Noninvasive Ventilation
• Other Study ID Numbers: 5173-1

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: UNDECIDED
• IPD Plan Description: Data will be made available upon reasonable request

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No