Efficiency and Safety of the Prolonged Use of Heat and Moisture Exchangers in ICU (FILTRex)

Safety and Efficiency of the Prolonged (72-hour) Use of a Single Heat and Moisture Exchanger in Adult Mechanically Ventilated Critically Ill and Its Impact on the Lower Respiratory Tract Pathogenic Microbial Colonisation Rate (FILTRex Trial); a Single-centre, Randomised, Controlled Trial

FILTRex is a single-centre, controlled, randomised, prospective, non-inferiority clinical trial to compare the efficiency and safety of prolonged (72-hours) versus standard (24-hours) duration of use for Heat and Moisture Exchange (HME) filters in adult mechanically ventilated critically ill patients

Study Overview

• Status: Not yet recruiting
• Conditions: VAP - Ventilator Associated Pneumonia
• Intervention / Treatment: Other: 72-hour HME exchange interval group; Other: 24-hour HME exchange interval group

Detailed Description

Rationale: Ventilator-associated pneumonia (VAP) is the most common hospital-acquired infection (HAI) in the intensive care unit (ICU), and its impact is very high in terms of morbidity, length of hospital stay and overall costs. Minimising manipulation and disconnection of the ventilator circuit by reducing the frequency of HME filter exchange may lower the risk of its secondary contamination, hence the incidence of VAP, while maintaining its efficacy in terms of sufficient humidification of the inhaled gas mixture and safety in terms of no or minimal change in resistance to airflow.

Aim: To test the effectiveness and safety of prolonged (72-hour exchange interval) use of a single HME.

Design: Prospective, single-centre, parallel-group randomised controlled trial. Subjects: ICU patients (general ICU)

Treatment in the intervention group: HME filter exchange every 72 hours

Control group: Standard-of-care: daily HME filter exchange

Primary outcome:

1. Presence of HME-associated adverse events (a composite endpoint of endotracheal tube occlusion or nosocomial tracheobronchitis or pneumonia).
2. The cumulative incidence of lower respiratory tract microbial colonisation analysed by the Kaplan-Maier method, censored in the case of ICU discharge or extubation > 24h.

Secondary and exploratory outcomes: Differences in the relative risk of infection-related ventilator-associated complications, antibiotics (ATB) exposure analysis, length of ICU stay in days (time frame: three months), number of ventilator-free days (time frame: 28 days); differences in the incidence of endotracheal tube occlusion necessitating reintubation between individual groups, differences in airway resistance, humidity delivered to the patients and efficacy of HMEs between groups

• Study Type: Interventional
• Enrollment (Estimated): 120
• Phase: Not Applicable

Participation Criteria

Eligibility Criteria

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

Description

Inclusion Criteria:

1. Age ≥18 years
2. In-patient in ICU and expected to stay > 3 days
3. Mechanical ventilation or imminent need of it; predicted length of mechanical ventilation ≥ 72h
4. Clinical Pulmonary Infection score (CPIS) less than six at the baseline 5 No history and symptoms of aspiration at the baseline

Exclusion Criteria:

1. Suspected pulmonary infection on admission and in the first 48 hours of mechanical ventilation
2. Pregnancy
3. Acute respiratory distress syndrome
4. Body temperature < 32°C
5. Airway bleeding or other contraindications for the use of HME
6. An early decision of treatment withdrawal

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Prevention
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: Double

Number of Arms

2

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: 72-hour HME exchange interval group; Intervention group: daily care will be provided according to the local standards, with an HME exchange interval every 72 hours	Other: 72-hour HME exchange interval group; All patients in the experimental arm will receive the usual best medical and nursing care with respect to VAP prevention. A dual-limb ventilator circuit with a closed suction system will be used. Bronchodilation or inhalational antibiotics, when ordered, will be delivered by a meshed nebuliser, a part of the ventilatory support circuit and will not be removed between treatments. A closed-circuit suction device will be used, and the frequency of suctioning will be monitored, including the sputum consistency and blood on suctioning. HME filter resistance by estimating the pressure drop over HME using the ventilatory circuit's auxiliary force (Paux) and flow. Temperature and humidity in the ventilator circuit will be measured. HME filters will be exchanged every 72 hours. At the exchange point, both outlets of the HME filter will be swabbed.
Active Comparator: 24-hour HME exchange interval group; Control group: daily care will be provided according to the local standards, with an HME exchange interval every 24 hours	Other: 24-hour HME exchange interval group; All patients in the control arm will receive the usual best medical and nursing care with respect to VAP prevention. A dual-limb ventilator circuit with a closed suction system will be used. Bronchodilation or inhalational antibiotics, when ordered, will be delivered by a meshed nebuliser, a part of the ventilatory support circuit and will not be removed between treatments. A closed-circuit suction device will be used, and the frequency of suctioning will be monitored, including the sputum consistency and blood on suctioning. HME filter resistance by estimating the pressure drop over HME using the ventilatory circuit's auxiliary force (Paux) and flow. Temperature and humidity in the ventilator circuit will be measured. HME filters will be exchanged every 24 hours. At the exchange point, both outlets of the HME filter will be swabbed.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Presence of HME-associated adverse events	A composite endpoint of nosocomial tracheobronchitis or pneumonia (all-cause, nosocomial and ventilator-associated) or endotracheal tube occlusion).	3 months
The cumulative incidence of lower respiratory tract microbial colonisation analysed by the Kaplan-Maier method, censored in the case of ICU discharge or extubation > 24h.	To detect microorganisms in the lower respiratory tract, tracheal aspirate will be directly cultured for detecting Gram-positive, Gram-negative, and anaerobic bacteria and fungi. Standard microbial surveillance (tracheal aspirate) will be performed on admission, twice a week (Monday, Thursday) and always ad hoc according to the clinical situation.	3 months

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Differences in the relative risk of infection-related ventilator-associated complications (IVAC) according to the Centers for Disease Control and Prevention (CDC) criteria.	Incidence rates among patients exposed to experimental intervention compared to those receiving standard care. We will establish the IVAC diagnosis based on the following: an increase of the daily minimum positive end-expiratory pressure (PEEP) of ≥3 cm of water column (H2O) and (or) the daily minimum inspired oxygen fraction (FiO2) of ≥20 points sustained for ≥2 days and; evidence of a new infection present (abnormal temperature or white blood cell count) and prescription of a new antibiotic for ≥4 days	3 months
ATB exposure analysis	Duration of antibiotics prescribed at discharge.	3 months
Length of ICU stay in days	that is, length in ICU stay in days	3 months
Number of ventilator-free days.	That is, the number of days, out of 28 days after admission, that the patient has not been supported by mechanical ventilation.	at 28 days

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
The length of ATB therapy until extubation, death or IVAC.	Cumulative percentage of days on the ventilator with ATB until extubation, death or IVAC.	3 months
The values of HME performance in vivo (temperature) during mechanical ventilation.	The absolute temperature of input, load, return, loss, yield, and thermal differential, their variation over time (72 hours) and the differences between in vivo obtained values of HME performance indicators and their laboratory values declared by the manufacturer in the technical sheet and prescribed by the international standard.	up to 30 days
The values of HME performance in vivo (humidity) during mechanical ventilation.	The absolute humidity of input, load, return, loss, yield, and thermal differential, their variation over time (72 hours) and the differences between in vivo obtained values of HME performance indicators and their laboratory values declared by the manufacturer in the technical sheet and prescribed by the international standard.	up to 30 days
The change in resistance of the HME filter from day 0 to day 2 (72 hours) and during drug nebulisation	The pressure drops over HME filter during mechanical ventilation.	up to 30days
The change in resistance of the HME filter during drug nebulisation	The pressure drop over HME filter during drug nebulisation.	up to 30 days

Collaborators and Investigators

• Sponsor: Charles University, Czech Republic

Study record dates

Study Major Dates

• Study Start (Estimated): May 1, 2024
• Primary Completion (Estimated): August 1, 2025
• Study Completion (Estimated): June 1, 2026

Study Registration Dates

• First Submitted: May 2, 2024
• First Submitted That Met QC Criteria: May 10, 2024
• First Posted (Actual): May 13, 2024

Study Record Updates

• Last Update Posted (Actual): May 13, 2024
• Last Update Submitted That Met QC Criteria: May 10, 2024
• Last Verified: May 1, 2024

More Information

Terms related to this study

• Keywords: pneumonia; endotracheal tube occlusion; Heat and Moisture Exchange (HME) filter; VAP bundle in ICU
• Additional Relevant MeSH Terms: Pathologic Processes; Infections; Respiratory Tract Infections; Respiratory Tract Diseases; Lung Diseases; Disease Attributes; Cross Infection; Iatrogenic Disease; Healthcare-Associated Pneumonia; Pneumonia; Pneumonia, Ventilator-Associated
• Other Study ID Numbers: VP/47/0/2022

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No