Targeting prEssure-Muscle-index to Avoid Ventilatory Over-Assistance During Pressure Support Ventilation
Trial statusRecruiting
Trial phaseNot applicable
Trial typeInterventional
Biological sexAll
Age18+
SponsorCentre for Medical Sciences
About this trial
The TEMA study (Targeting prEssure-Muscle-index to avoid ventilatory over-Assistance during pressure support ventilation) is a prospective, interventional crossover trial investigating the relationship between pressure support (PS) and tidal volume (Vt) in ICU patients with acute hypoxemic respiratory failure (AHRF) receiving pressure support ventilation (PSV). The study aims to assess whether the Pressure-Muscle Index (PMI)-a marker derived from the difference between plateau and peak inspiratory pressure-can help identify the optimal level of ventilatory assistance, preventing over-assistance and its associated complications such as diaphragm atrophy and patient self-inflicted lung injury (P-SILI). By exploring the sigmoidal relationship between PS and Vt, the study seeks to define a physiological threshold (PMI=0) that may serve as a personalized target for PSV titration.
Eligibility criteria
This trial does not accept healthy volunteersQualifiers
Age ≥ 18 years
Mechanically ventilated in the ICU
Diagnosis of Acute Hypoxemic Respiratory Failure (AHRF)
Normocapnia or non-severe hypercapnia
Disqualifiers
Age < 18 years
Known neurological or neuromuscular disorders affecting diaphragm function
Chronic Obstructive Pulmonary Disease (COPD) or hypercapnic respiratory failure
Psychomotor agitation or inadequate sedation
Trial design
Design model
Crossover
Treatments tested in this trial
Variation of Pressure Support Levels
Procedure/SurgeryPatients will undergo six randomized PS levels (+2, +4, +6 cmH₂O above and -2, -4, -6 cmH₂O below PSPMI=0).
Treatment groups
36 Participants
are divided into 7 treatment groups7
Treatment groupsSee each treatment group below.
Group A: Pressure Support PMI=0Experimental treatment 1 intervention
Group B: Pressure Support +2Experimental treatment 1 intervention
Group C: Pressure Support +4Experimental treatment 1 intervention
Group D: Pressure Support +6Experimental treatment 1 intervention
Group E: Pressure Support -2Experimental treatment 1 intervention
Group F: Pressure Support -4Experimental treatment 1 intervention
Group G: Pressure Support -6Experimental treatment 1 intervention
Trial outcomes
Primary outcomes
1
Pressure Support-Tidal Volume (PS-Vt) Relationship
The primary aim is to determine whether the PS-Vt curve exhibits a flat region (where tidal volume remains stable) before transitioning into a steep, compliance-dependent increase at higher PS levels. This transition point, identified as PSPMI=0, is hypothesized to represent the threshold for over-assistance.
Time frame
Up to 5 minutes after each PS level adjustment during the interventional phase (Day 1)Secondary outcomes
1
Validation of Pressure-Muscle Index (PMI) as an Over-Assistance Marker
PMI will be tested as a real-time bedside indicator for detecting over-assistance in PSV. The study will assess whether PMI=0 reliably corresponds to the threshold of over-assistance, characterized by a minimal patient contribution to Vt and a linear increase in Vt proportional to PS.
Time frame
Up to 5 minutes after each PS level adjustment during the interventional phase (Day 1) and during follow-up assessment on Days 4-6 (if patient remains intubated)2
Impact of Respiratory Mechanics on PS-Vt Relationship
Evaluation of how respiratory compliance (Crs) influence the PS-Vt curve. The study will investigate individual variations in ventilatory response to PS.
Time frame
During the interventional phase on Day 1 and during follow-up assessment on Days 4-6 (if patient remains intubated)3
Rate of Ineffective Efforts During Over-Assistance
Quantification of ineffective respiratory efforts (i.e., inspiratory efforts not followed by ventilator-triggered breaths) during PS levels exceeding the identified PSPMI=0 threshold.
Time frame
Up to 5 minutes after each PS level adjustment during the interventional phase (Day 1) and during follow-up assessment on Days 4-6 (if patient remains intubated)4
Effect of Over-Assistance on Ventilatory Asynchronies
Measurement of the asynchrony index (percentage of breaths with any form of patient-ventilator asynchrony) at different levels of pressure support, particularly above PSPMI=0.
Time frame
Up to 5 minutes after each PS level adjustment during the interventional phase (Day 1) and during follow-up assessment on Days 4-6 (if patient remains intubated)Sponsors and contacts
Click on the lead sponsor to view all of their trials.
Centre for Medical Sciences
Lead sponsor
Università degli Studi di Trento
Sponsor institution
Source ClinicalTrials.gov