Inspiratory-effort–targeted pressure support for adults on ventilators

A Cluster Randomized Trial on Inspiratory Effort-Based Pressure Support Adjustment Strategy in Patients Undergoing Assisted Mechanical Ventilation

This study will test whether using inspiratory effort measured by the pressure muscle index to set pressure support helps adults with acute hypoxic respiratory failure on ventilators have better outcomes than the usual tidal volume and respiratory rate approach.

Quick facts

• Phase: NA
• Study type: Interventional
• Enrollment: 619 (estimated)
• Ages: 18 Years and up
• Sex: All
• Sponsor: Capital Medical University (other)
• Locations: 1 site (Beijing, Beijing Municipality)
• Trial ID: NCT06526598 on ClinicalTrials.gov

What this trial studies

This is a two-arm, cluster randomized trial comparing a pressure support setting strategy guided by inspiratory effort (using the pressure muscle index, PMI) with the traditional tidal volume and respiratory rate (VT/RR)–guided strategy. Eighteen clusters are randomized 1:1 to either PMI-targeted or VT/RR-targeted pressure support, with usual ICU care protocols for triggers, cycle-off, FiO2, PEEP, spontaneous breathing trials, and weaning maintained. Adult patients intubated within seven days, started on pressure support within 24 hours, and with PaO2/FiO2 ≤ 300 are enrolled and followed for clinical outcomes related to ventilation and recovery. The trial tests whether matching ventilator assistance to measured inspiratory effort reduces over-assistance and improves meaningful patient outcomes.

Who should consider this trial

Good fit: Adults in the ICU with acute hypoxic respiratory failure who were intubated within the prior seven days, started on pressure support within 24 hours, have PaO2/FiO2 ≤ 300, and are awake or lightly sedated (RASS -2 to +1 or SAS 3–4) are ideal candidates.

Not a fit: Patients with neuromuscular disease, suspected raised intracranial pressure, on extracorporeal support, moribund patients, those ventilated >7 days before enrollment, or those intubated prior to ICU admission are unlikely to benefit from this intervention.

Why it matters

Potential benefit: If successful, the PMI-targeted approach could reduce ventilator-induced lung injury and shorten duration of mechanical ventilation and ICU stay.

How similar studies have performed: Physiological and observational studies have shown frequent over-assistance with PSV and that PMI can track inspiratory effort at the bedside, but randomized trials testing a PMI-targeted pressure support strategy are limited and this approach is relatively novel.

Eligibility criteria

Mechanically ventilated patients, who are admitted to the ICU with acute hypoxic respiratory failure, will be consecutively screened daily at 08:00-10:00 morning rounds.

Inclusion criteria:

1. PSV initiated during the last 24 hours;
2. Mechanical ventilation expected to be required for at least 24-48 h by responsible physicians;
3. The partial pressure of oxygen in arterial blood (PaO2)/inspired oxygen fraction (FiO2) ≤ 300 mmHg (measuring at clinical FiO2 and positive end-expiratory pressure PEEP);
4. No sedation or stable sedation with Richmond Agitation Sedation Scale (RASS) of -2 to +1 or Riker's Sedation-Agitation Scale (SAS) of 3 to 4.

Exclusion criteria included:

1. Age younger than 18 years old;
2. Initiation of PSV before ICU admission;
3. Duration of mechanical ventilation longer than 7 days before enrollment;
4. History of neuromuscular diseases;
5. Clinical suspicion of increased intracranial pressure;
6. Extracorporeal support;
7. Moribund conditions;
8. Refusal by the ICU physicians or the patient.

Where this trial is running

Beijing, Beijing Municipality

• Beijing Shijitan Hospital — Beijing, Beijing Municipality, China (RECRUITING)

Study contacts

• Principal investigator: Jian-Xin Zhou, MD — Capital Medical University
• Study coordinator: Jian-Xin Zhou, MD

Conditions: Critical Care, Acute Hypoxic Respiratory Failure, Ventilator-Induced Lung Injury, pressure support ventilation, pressure muscle index, inspiratory effort