Clinical Comparison of Different Humidification Strategies During Noninvasive Ventilation With Helmet

NCT02875379 | Completed

• 1 other identifier: 11491/15
• Study Type: interventional
• Target: 20
• Locations: 1 country
• Sites: 1

Brief Summary

Background. Non invasive positive pressure ventilation (NIV) is among first line treatments of acute respiratory failure. Several interfaces are available for non-invasive ventilation.Despite full face and oronasal masks are more frequently used, some evidence suggests that helmets may optimize patients' comfort and NIV tolerability. During NIV, humidification strategies (heat and moisture exchangers HME or heated humidifiers HH) may significantly affect patient's comfort and work of breathing. Despite physiological data suggested heated humidification as the best strategy during NIV with full face masks, no differences were found in a randomized controlled study assessing the effects of HME or HH on a pragmatic clinical outcome. However, the higher dead space (i.e. 18 L/min) and rebreathing rate observed during helmet NIV make such results not applicable to this particular setting. The investigators designed a randomized-crossover trial to assess the effect of four humidification strategies during helmet NIV on patients with acute respiratory failure, in terms of comfort, work of breathing and patient-ventilator interaction. Methods. All awake, collaborative, hypoxemic patients requiring mechanical ventilation will be considered for the enrollment. Hypercapnic patients (i.e.PaCO2\>45 mmHg) will be excluded. Each enrolled patient will undergo helmet NIV with all the following humidification strategies in a random order. Each period will last 60 minutes.

• Passive humidification, double tube circuit.
• Heated humification (MR 730, Fisher \& Paykel, Auckland, New Zealand), humidification chamber temperature 33°C.
• Heated humification (MR 730, Fisher \& Paykel, Auckland, New Zealand), humidification chamber temperature 37°C.
• Passive humidification with HME, Y-piece circuit. Ventilatory settings (Draeger Evita xl or Evita infinity ventilators): Pressure support ventilation; pressure support=20 cmH20; FiO2 titrated to obtain SpO2 between 92 and 98%; positive end-expiratory pressure=10 cmH2O; maximum inspiratory time 0.9 seconds; inspiratory flow trigger = 2 l/min; expiratory trigger: 30% of the maximum inspiratory flow; pressurization time=0,00 s. Such settings will be kept unchanged during the whole study period. An oesophageal catheter will be placed and secured to measure oesophageal pressure (Pes) and gastric pressure (Pga) (Nutrivent, Italy): the reliability of the measured pressure will be confirmed with an airway occlusion test during NIV with oronasal mask. Work of breathing will be estimated with the pressure-time product (PTP) of the pleural pressure. A pneumotachograph (KleisTek) will record flow, airway pressure, Pes and Pga on a dedicated laptop. At the end of each cycle, the patient will be asked to rate his/her discomfort on a visual analog scale (VAS) modified for ICU patients. The level of dyspnea will be assessed with the Borg dyspnea scale. The following parameters will be record at the end of each cycle: Arterial pressure, heart rate, respiratory rate, SpO2, pH, PCO2, PaO2, SaO2. Airway and esophageal pressure signals will be reviewed offline to detect patient-ventilator asynchronies (ineffective efforts, double cycling, premature cycling, delayed cycling) and asynchrony index (number of asynchrony events divided by the total respiratory rate computed as the sum of the number of ventilator cycles (triggered or not) and of wasted efforts) will be computed. The trigger delay will be also measured. The pressurization and depressurization velocity will be assessed with the PTP airway index 300 and 500 (inspiratory and expiratory), as suggested by Ferrone and coworkers. The work of breathing (WOB) for each breath will be estimated by PTPes. An hygrometer (Dimar SRL, Italy) will measure and record on a dedicated laptop Helmet temperature, relative and absolute humidity. Primary endpoints: patient's comfort, work of breathing and asynchrony index. Sample Sizing: Given the physiological design of the study, the investigators did not make an a priori sample size and plan to enroll 24 patients.

Conditions

Respiratory Failure

Keywords

Noninvasive Ventilation; Mechanical Ventilation

Outcome Measures

Primary Outcomes (3)

• Comfort assessed by visual analogic scale modified for ICU patients

  Patient's comfort, assessed by visual analogic scale modified for ICU patients

  At the end of each 1-hour ventilation period

• Patient-ventilator asynchrony. Asynchrony index

  Asynchrony index number of asynchrony events divided by the total respiratory rate computed as the sum of the number of ventilator cycles (triggered or not) and of wasted efforts. Inspiratory trigger delay (time between the onset of patient's effort and ventilatory support). Pressurization and depressurization efficacy.

  At the end of each 1-hour ventilation period

• Work of breathing. Oesophageal pressure time product

  Pressure time product of the esophageal pressure (PTPes) and pressure time product of the transdiaphragmatic pressure (PTPdi)

  At the end of each 1-hour ventilation period

Secondary Outcomes (6)

• PaO2

  At the end of each 1-hour ventilation period

• respiratory rate

  At the end of each 1-hour ventilation period

• Dyspnea

  At the end of each 1-hour ventilation period

• Helmet humidity

  At the end of each 1-hour ventilation period

• Helmet temperature

  At the end of each 1-hour ventilation period

Study Arms (4)

HME

EXPERIMENTAL

Passive humidification with heat and moisture exchanger, Y-piece circuit.

Procedure: Measurements

HH33

EXPERIMENTAL

Heated humification (MR 730, Fisher \& Paykel, Auckland, New Zealand), humidification chamber temperature 33°C.

Procedure: Measurements

HH37

EXPERIMENTAL

Heated humification (MR 730, Fisher \& Paykel, Auckland, New Zealand), humidification chamber temperature 33°C.

Procedure: Measurements

NoH

EXPERIMENTAL

Passive humidification, double tube circuit

Procedure: Measurements

Interventions

Measurements PROCEDURE

Measurements of respiratory mechanics and parameters, arterial blood gases and comfort

HH33; HH37; HME; NoH

Eligibility Criteria

• Age: 18 Years+
• Sex: all
• Healthy Volunteers: No
• Age Groups: Adult (18-64), Older Adult (65+)

You may qualify if:

• Awake and collaborative patients
• Age\>18 years
• Need for noninvasive mechanical ventilation
• Informed consent

You may not qualify if:

• Cardiopulmonary resuscitation
• Haemodynamic instability
• Coma
• Asma
• Hypercapnia (paCO2\>45 mmHg)
• Recent gastric or abdominal surgery

Sponsors & Collaborators

• Catholic University of the Sacred Heart: lead

Study Sites (1)

General ICU, A. Gemelli hospital

Rome, 00100, Italy

Location

Related Publications (1)

• Bongiovanni F, Grieco DL, Anzellotti GM, Menga LS, Michi T, Cesarano M, Raggi V, De Bartolomeo C, Mura B, Mercurio G, D'Arrigo S, Bello G, Maviglia R, Pennisi MA, Antonelli M. Gas conditioning during helmet noninvasive ventilation: effect on comfort, gas exchange, inspiratory effort, transpulmonary pressure and patient-ventilator interaction. Ann Intensive Care. 2021 Dec 24;11(1):184. doi: 10.1186/s13613-021-00972-9.

  PMID: 34952962 DERIVED

MeSH Terms

Conditions

Respiratory Insufficiency

Interventions

Weights and Measures

Condition Hierarchy (Ancestors)

Respiration Disorders; Respiratory Tract Diseases

Intervention Hierarchy (Ancestors)

Investigative Techniques

Study Design

• Study Type: interventional
• Phase: not applicable
• Allocation: RANDOMIZED
• Masking: NONE
• Purpose: TREATMENT
• Intervention Model: CROSSOVER
• Sponsor Type: OTHER
• Responsible Party: PRINCIPAL INVESTIGATOR
• PI Title: M.D. Full Professor of Anesthesiology and Intensive Care. Head of the department of Anesthesiology and Intensive Care medicine

Study Record Dates

• First Submitted: July 27, 2015
• First Posted: August 23, 2016
• Study Start: February 1, 2017
• Primary Completion: January 23, 2019
• Study Completion: January 23, 2019
• Last Updated: January 24, 2019

Record last verified: 2019-01

Locations

IT (1)