Proportional Assist Ventilation, Respiratory Effort, Work of Breathing
Conditions
Brief summary
In intensive care units, many critically ill patients need help from a machine called a ventilator to breathe. Once these patients start to recover, doctors try to gradually reduce this support and help them breathe on their own again. However, not all patients are ready to be taken off the ventilator right away. During this transition, it's important to find the right amount of help-enough to support their breathing, but not so much that the machine does all the work for them. This study focuses on a special type of ventilator setting called Proportional Assist Ventilation Plus (PAV+). Unlike traditional modes, which give a fixed level of support, PAV+ adjusts the amount of help it gives based on how hard the patient is trying to breathe. The more effort a patient makes, the more support the machine provides-and vice versa. This can make breathing feel more natural and may protect the lungs and breathing muscles during recovery. Modern ventilators also display a measurement called Work of Breathing, which tells how much effort the patient is using to breathe. This study wants to find out whether this measurement from the ventilator is a reliable way to monitor a patient's breathing effort, compared to other more invasive or complex methods. The research will include 20 adult patients who are recovering in the ICU and have been on mechanical ventilation for more than 48 hours. All patients will have already met some criteria showing they're ready to begin breathing more on their own, but are not quite ready to have the breathing tube removed. Each patient will go through different levels of PAV+ support, and researchers will record how much effort they make to breathe using several methods, including special pressure sensors and data from the ventilator. The goal of the study is to better understand how to measure breathing effort safely and easily, and to improve how we support patients as they recover the ability to breathe on their own. If successful, this could help reduce complications and improve recovery for people on ventilators. There are no added risks or costs for the patients involved. All equipment used in the study is already part of regular ICU care. Participation requires informed consent and the privacy of all participants will be fully protected.
Interventions
OTHERApplication of Proportional Assist Ventilation Plus (PAV+) at three support levels (20%, 50%, 70%) to assess ventilator-displayed work of breathing and its correlation with physiologic measures.
This intervention is distinguished by applying Proportional Assist Ventilation Plus (PAV+) at three support levels (20%, 50%, 70%) within the same patient, allowing a stepwise analysis of its effect on work of breathing. It uses real-time ventilator-displayed work of breathing, a noninvasive and underexplored tool, correlated with multiple physiological parameters such as esophageal pressure, Pocc, and P0.1. This within-subject design controls for interindividual variability, improving the precision of the analysis. Focusing on patients with spontaneous respiratory effort facilitates clinical application to optimize personalized ventilatory support. Thus, the study provides novel data to adjust support levels according to the patient's actual effort and to validate ventilator measurements against reference physiological indicators.
Sponsors
Argentinian Intensive Care Society
Study design
Observational model
COHORT
Time perspective
PROSPECTIVE
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Adults (\>18 yrs) requiring invasive MV \>48 hrs * Meeting spontaneous breathing transition criteria: * Hemodynamic stability (NE \<0.1 μg/kg/min) * Spontaneous breathing efforts * RASS -2 to +1 * FiO₂ \<50% or PaO₂ \>60mmHg with PEEP ≤10cmH₂O * Pre-existing esophageal balloon * Tolerates spontaneous modes \>5 mins * Signed informed consent
Exclusion criteria
* Meets extubation criteria * Hemodynamic instability * Psychomotor agitation (RASS \>+1) * Bronchopleural fistula * Severe weakness (MRC \<36) * Neuromuscular disease * Pregnancy
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Correlation Between Ventilator-Measured Work of Breathing Tool and and invasive respiratory effort markers | From enrollment to the end of measurents at 3 hours | Correlation between non-invasive WOB (measured by Puritan Bennett™ ventilators tool) and invasive metrics (Pes/PTPes via esophageal catheter, in cmH₂O and cmH₂O·s) during PAV+. Analyzed across 3 assistance levels (20%/50%/70%) to validate ventilator-based effort monitoring. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Pocc (expiratory occlusion pressure in cmH₂O) during PAV+ analyzed across 3 assistance levels (20%/50%/70%) to validate ventilator-based effort monitoring. | From enrollment to the end of measurements at 3 hours | Validate ventilator-measured WOB against Pocc (cmH₂O) in PAV+ measures compared at 20%/50%/70% assistance to assess non-invasive monitoring accuracy. |
| P0.1 (inspiratory occlusion pressure at 100 mseg in cmH₂O) during PAV+ analyzed across 3 assistance levels (20%/50%/70%) to validate ventilator-based effort monitoring. | From enrollment to the end of measurements at 3 hours | Validate ventilator-measured WOB against P0.1 (cmH₂O) in PAV+ measures compared at 20%/50%/70% assistance to assess non-invasive monitoring accuracy. |
Countries
Argentina
Outcome results
None listed