Ventilator Weaning, Respiratory Insufficiency
Conditions
Keywords
Diaphragm Ultrasonography, Diaphragm Thickening Fraction, Diaphragm Excursion, Rapid Shallow Breathing Index, Extubation, Spontaneous Breathing Trial, Intensive Care Unit
Brief summary
The purpose of this study is to find out whether diaphragm ultrasound measurements, alone or combined with the rapid shallow breathing index (RSBI), can better predict successful removal of the breathing tube in adult intensive care unit patients on mechanical ventilation. Diaphragm thickening fraction and diaphragm excursion are measured with bedside ultrasound during the spontaneous breathing trial. Patients are followed after extubation to determine whether they need to be reintubated. The study does not change patient treatment; all measurements are non-invasive.
Detailed description
Weaning from mechanical ventilation is a critical phase of intensive care. Premature extubation increases the risk of reintubation, whereas delayed extubation increases ventilator-associated complications. The rapid shallow breathing index (RSBI) is widely used but has limited accuracy on its own. Diaphragm ultrasound, including diaphragm thickening fraction (DTF), has emerged as a reliable method for assessing diaphragm function. This prospective, observational, single-center study is conducted in the Reanimation Intensive Care Unit of Inonu University Turgut Ozal Medical Center, Malatya, Turkey. Adult patients who have received invasive mechanical ventilation for at least 48 hours and are scheduled for a spontaneous breathing trial (SBT) are enrolled after informed consent is obtained from a legally authorized representative. RSBI is calculated before the SBT. Right hemidiaphragm ultrasound is performed by the same investigator in all patients, who is blinded to the RSBI value and the extubation decision. DTF is measured at the beginning and at the end of the SBT, and the change in DTF between the two measurements is calculated. Diaphragm excursion is also recorded. The primary indication for mechanical ventilation is recorded using a predefined hierarchy. The primary outcome is extubation success, defined as the absence of reintubation or of respiratory failure not manageable with non-invasive ventilation or high-flow oxygen therapy within 48 hours after extubation. The diagnostic performance of DTF, diaphragm excursion, and RSBI, alone and in combination will be compared using receiver operating characteristic curve analysis with the combined DTF+RSBI model derived from logistic regression. The planned sample size is 80 patients.
Interventions
DIAGNOSTIC_TESTDiaphragm Ultrasonography
Right hemidiaphragm ultrasound measuring diaphragm thickening fraction at the beginning and end of the spontaneous breathing trial, the change between the two, and diaphragm excursion. Performed by a single investigator blinded to RSBI and the extubation decision.
DIAGNOSTIC_TESTRapid Shallow Breathing Index
Ratio of respiratory frequency to tidal volume (breaths/min/L) calculated before the spontaneous breathing trial.
Sponsors
Inonu University
Study design
Observational model
COHORT
Time perspective
PROSPECTIVE
Eligibility
Sex/Gender
ALL
Age
18 Years to No maximum
Healthy volunteers
No
Inclusion criteria
* Age 18 years or older * Invasive mechanical ventilation via an orotracheal or nasotracheal tube for at least 48 hours * Planned spontaneous breathing trial * Meeting weaning criteria with a clinical decision for extubation * Informed consent obtained from a legally authorized representative
Exclusion criteria
* Diaphragm paralysis * Neuromuscular disease * High cervical spinal cord injury * Pregnancy * Inadequate ultrasound image quality * Tracheostomy * Severe obesity (BMI \> 35-40 kg/m2) * Advanced COPD or chronic respiratory failure * History of phrenic nerve injury (e.g., after cardiac surgery) * Neuromuscular blocking agent administration within the previous 24 hours * Inability to cooperate with the SBT due to severe agitation or delirium * Palliative/terminal care or life expectancy of less than 24 hours
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Diagnostic Performance of Combined DTF and RSBI for Predicting Extubation Success | 48 hours after extubation | Area under the receiver operating characteristic curve (AUC) of the combined diaphragm thickening fraction and RSBI model compared with RSBI alone for predicting extubation success, defined as no reintubation and no respiratory failure unmanageable with non-invasive ventilation or high-flow oxygen therapy. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Diaphragm Thickening Fraction | At the beginning and at the end of the spontaneous breathing trial | Right hemidiaphragm thickening fraction measured by ultrasonography, calculated as (end-inspiratory thickness minus end-expiratory thickness) divided by end-expiratory thickness, expressed as a percentage. |
| Change in Diaphragm Thickening Fraction During the Spontaneous Breathing Trial | From the beginning to the end of the spontaneous breathing trial | Difference between diaphragm thickening fraction measured at the end and at the beginning of the spontaneous breathing trial, in percentage points. |
| Diaphragm Excursion | At the end of the spontaneous breathing trial | Right hemidiaphragm excursion measured by M-mode ultrasonography, in centimeters. |
| Rapid Shallow Breathing Index | Before the spontaneous breathing trial | Ratio of respiratory frequency to tidal volume, in breaths/min/L. |
| Hospital Mortality | From extubation up to 28 days | Number of participants who died from any cause during the hospital stay. |
| ICU Length of Stay | From ICU admission to ICU discharge, assessed up to 28 days | Length of intensive care unit stay, in days. |
| Hospital Length of Stay | From hospital admission to hospital discharge, assessed up to 28 days | Total length of hospital stay, in days. |
| Reintubation Within 7 Days | 7 days after extubation | Proportion of patients requiring reintubation within 7 days after extubation. |
| ICU Mortality | From extubation up to 28 days | Number of participants who died from any cause during the intensive care unit stay. |
Contacts
CONTACTGöksel Aydoğan, MD
PRINCIPAL_INVESTIGATORAyşe Belin Özer, MD, Prof.
Intensive Care Unit, Inonu University turgut Ozal Medical Center,Malatya, Türkiye
Outcome results
None listed