Non-invasive Respiratory Monitoring During SBT

Noninvasive Assessment of Respiratory Mechanics, Inspiratory Effort, and Respiratory Drive During Spontaneous Breathing Trial to Predict Extubation Failure in High-Risk Patients

Spontaneous breathing trials (SBTs) assess readiness for extubation, yet the use of conventional parameters used to establish weaning success may be elusive, especially in high-risk patients. Currently, non-invasive techniques allow comprehensive bedside assessment of advanced respiratory mechanics, including metrics of respiratory system compliance (CRS), respiratory muscle effort (POCC) and respiratory drive intensity (P0.1). This study investigates whether these measurements during SBT may improve the prediction of extubation outcomes

Study Overview

• Status: Completed
• Conditions: Mechanical Ventilation Complication; Acute Respiratory Failure; Re-intubation Rate

• Study Type: Observational
• Enrollment (Actual): 238

Contacts and Locations

Study Locations

• Italy
  • Bari, Italy, 70124
    • Salvatore Grasso
  • Bari, Italy, 70124
    • Azienda Ospedaliero Universitaria Policlinico

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: 18 years to 100 years (Adult, Older Adult)
• Accepts Healthy Volunteers: No

• Sampling Method: Probability Sample

Study Population

High-risk patients for re-intubation were defined as follow :

The presence of ≥ 1 among the following factors to define the high-risk for re-intubation: age older than 65 years; heart failure as the primary indication for mechanical ventilation; moderate to severe chronic obstructive pulmonary disease (COPD); an Acute Physiology and Chronic Health Evaluation II (APACHE II) score higher than 12 on extubation day; body mass index of more than 30; inadequate cough reflex or suctioning >2 times within 8 hours before extubation; prolonged use of invasive ventilation (≥ 7 days from the first SBT); more than 2 comorbidities categorized based on the Charlson Comorbidity Index.

Description

To be eligible, patients had to meet all of the following criteria:

1. Age ≥ 18 years.
2. The presence of ≥ 1 among the following factors to define the high-risk for re-intubation: age older than 65 years; heart failure as the primary indication for mechanical ventilation; moderate to severe chronic obstructive pulmonary disease (COPD); an Acute Physiology and Chronic Health Evaluation II (APACHE II) score higher than 12 on extubation day; body mass index of more than 30; inadequate cough reflex or suctioning >2 times within 8 hours before extubation; prolonged use of invasive ventilation (≥ 7 days from the first SBT); more than 2 comorbidities categorized based on the Charlson Comorbidity Index.
3. Deemed ready to be weaned from the ventilator, based on the following criteria: (a) invasive mechanical ventilation for more than 48 hours, including at least 12 hours of pressure support ventilation with PEEP ≤ 8 cmH2O and pressure support ≤ 10 cmH2O; (b) Improvement of the condition leading to intubation; (c) patient making inspiratory effort; (d) adequate gas exchange, as indicated by a ratio of partial pressure of arterial oxygen (PaO2) to inspiratory fraction of oxygen (FiO2) ≥ 150 with FiO2 ≤ 40% and arterial pH within normal range (7.30 - 7.50); (e) Glasgow Coma Score higher than 13; (f) a core temperature below 38°C; (g) Richmond agitation and sedation scale between -1 and +1.

Eligibility required readiness for scheduled extubation after successfully completing a 30-minute SBT in the pressure-support mode (7 cmH₂O)

SBT success was defined by the following criteria [19]: (a) adequate gas exchange, as indicated by a ratio of partial pressure of arterial oxygen (PaO2) to inspiratory fraction of oxygen (FiO2) ≥ 150 with FiO2 ≤ 40% and arterial pH within the normal range (7.30 - 7.50); (b) respiratory rate < 35/min; (c) spontaneous tidal volume higher than 5 ml of predicted body weight (PBW); (d) a ratio of respiratory rate to tidal volume (i.e. the rapid shallow breathing index, RSBI) < 105/min per liter; (e) systolic blood pressure between 90 and 160 mmHg and heart rate < 140/min, with or without low doses of vasopressors (< 0.5 mcg/kg/min). Exclusion criteria were tracheostomy, patients undergoing withdrawal of life-sustaining treatments, known neuromuscular diseases.

Study Plan

How is the study designed?

Design Details

• Observational Models: Case-Only
• Time Perspectives: Prospective

Number of groups / cohorts

1

Cohorts and Interventions

Group / Cohort
Patients at high-risk for re-intubation

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Advance Respiratory mechanics assessment during SBT	The primary endpoint was to establish whether changes in CRS, POCC and P0.1 and/or their absolute values at the end of the PAV+ SBT differed between patients who subsequently required reintubation vs. those who were successfully extubated	30 minutes

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
discriminatory power	we aimed to test the discriminatory power of the absolute values of CRS, POCC and P0.1 at the end of SBT and discriminatory power of the SBT-induced percentage changes in these measurements during the trial in identifying patients who failed extubation.The decision to reintubate was made by the attending physicians, who were unaware of the study measurements results.	72 hours

Collaborators and Investigators

• Sponsor: University of Bari
• Collaborators: Catholic University of the Sacred Heart; Università degli Studi di Ferrara; University of Turin, Italy; University of Sassari, Italy

Study record dates

Study Major Dates

• Study Start (Actual): September 1, 2022
• Primary Completion (Actual): April 1, 2024
• Study Completion (Actual): April 1, 2024

Study Registration Dates

• First Submitted: March 9, 2022
• First Submitted That Met QC Criteria: March 21, 2022
• First Posted (Actual): March 25, 2022

Study Record Updates

• Last Update Posted (Actual): March 25, 2025
• Last Update Submitted That Met QC Criteria: March 4, 2025
• Last Verified: April 1, 2024

More Information

Terms related to this study

• Keywords: noninvasive monitoring; Extubation failure; spontaneous breathing trial; lung mechanics; airway occlusion pressure
• Additional Relevant MeSH Terms: Respiratory Tract Diseases; Respiration Disorders; Respiratory Insufficiency
• Other Study ID Numbers: SBT_PAV01

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: No
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No