Dynamic POCUS of Diaphragm Function to Predict Respiratory Failure in Septic Shock (POCUS in RF)

September 11, 2026 updated by: Abdallah Gamal Abd El Hafeez Haridy, Assiut University

Dynamic Point of Care Ultrasound (POCUS) Imaging Assessment of Diaphragmatic Function as a Predictor of Respiratory Failure and Clinical Outcomes in Patients With Septic Shock.

This prospective observational cohort study aims to evaluate the prognostic value of serial bedside ultrasound assessment of diaphragmatic function in adult patients with septic shock. Diaphragmatic excursion, thickness, and thickening fraction will be assessed using point of care ultrasound at baseline and serially during the first 72 hours of intensive care admission. Dynamic changes in these parameters will be analyzed in relation to the development of respiratory failure, need for invasive mechanical ventilation, duration of mechanical ventilation, weaning and extubation outcomes, length of ICU stay, and mortality. The study will determine whether dynamic diaphragmatic ultrasound assessment can provide an early, non-invasive predictor of respiratory failure and adverse clinical outcomes in patients with septic shock.

Study Overview

Status

Not yet recruiting

Conditions

Detailed Description

Septic shock remains a major cause of morbidity and mortality among critically ill patients. Respiratory failure is a frequent and serious complication, resulting from a combination of sepsis-induced lung injury, acute respiratory distress syndrome, respiratory muscle dysfunction, and sepsis-induced myopathy. The diaphragm is the principal muscle of respiration and may be significantly affected during sepsis. Systemic inflammation, altered microcirculation, mitochondrial dysfunction, electrolyte abnormalities, prolonged immobilization, sedation, and mechanical ventilation can contribute to diaphragmatic dysfunction. Such dysfunction may impair spontaneous breathing, increase the risk of respiratory failure, prolong mechanical ventilation, and contribute to unsuccessful weaning and adverse clinical outcomes. Point-of-care ultrasound (POCUS) provides a non-invasive, bedside, radiation-free method for assessing diaphragmatic structure and function. The most commonly used parameters include diaphragmatic excursion (DE), diaphragmatic thickness, and diaphragmatic thickening fraction (DTF). Most available studies have assessed diaphragmatic function at a single point in time, particularly during weaning from mechanical ventilation. However, limited evidence exists regarding the prognostic value of serial dynamic assessment of diaphragmatic function in patients with septic shock from the early stages of ICU admission.

Dynamic changes in diaphragmatic function may provide more clinically meaningful information than a single measurement. Therefore, serial POCUS assessment may help identify patients at high risk of respiratory failure and predict important clinical outcomes.

Study Type

Observational

Enrollment (Estimated)

120

Contacts and Locations

This section provides the contact details for those conducting the study, and information on where this study is being conducted.

Study Contact

Name: Abdallah Gamal Abd El Hafeez, Master
Phone Number: +0201221248314
Email: abdallah.gamal0111@med.aun.edu.eg

Study Contact Backup

Name: Dina Ali Ahmed, MD
Phone Number: +0201063040703
Email: dinaalihamad@aun.edu.eg

Study Locations

Egypt
- - Asyut, Egypt, 71515
    - Faculty of medicine, Assiut university

Participation Criteria

Researchers look for people who fit a certain description, called eligibility criteria. Some examples of these criteria are a person's general health condition or prior treatments.

Eligibility Criteria

Ages Eligible for Study

Adult
Older Adult

Accepts Healthy Volunteers

Sampling Method

Non-Probability Sample

Study Population

The study population will consist of adult patients 18 years old or more admitted to ICU with septic shock diagnosed according to the sepsis-3 criteria. Eligible patients will be prospectively enrolled after meeting the predefined inclusion and exclusion criteria and will undergo serial bedside point of care ultrasound assessment of diaphragmatic function during the first 72 hours of ICU admission.

Description

Inclusion Criteria:

Age ≥ 18 years old.
Patients with septic shock.
Patients with ICU admission during study period.
Expected ICU stay for at least 72 hours.
Informed consent from the patient or legal guardian when required.

Exclusion Criteria:

Age less than 18 years old.
Pre-existing neuromuscular disorders affecting respiratory muscles.
Known diaphragmatic paralysis or diaphragmatic palsy.
Significant phrenic nerve injury.
Cervical spinal cord injury.
Advanced chronic neuromuscular disease.
Previous major thoracic or diaphragmatic surgery.
Severe chest wall deformity.
Conditions preventing adequate diaphragmatic ultrasound assessment.
Pregnancy, if required by local ethical policy.
Patients with limitations of care that preclude full respiratory support.
Refusal of consent where consent is required.

Study Plan

This section provides details of the study plan, including how the study is designed and what the study is measuring.

How is the study designed?

Design Details

Number of groups / cohorts

Cohorts and Interventions

Group / Cohort
Patients with septic shock who are not receiving invasive mechanical ventilation at enrollment. Patients with septic shock who are not receiving invasive mechanical ventilation at enrollment. primary respiratory outcome: Development of respiratory failure requiring invasive mechanical ventilation within 7 days after enrollment.
Patients with septic shock who are already receiving invasive mechanical ventilation at enrollment. Patients with septic shock who are already receiving invasive mechanical ventilation at enrollment. outcomes: Duration of mechanical ventilation, weaning failure, extubation failure or reintubation, ICU and hospital mortality and ICU length of stay.

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Number of participants Developing Respiratory Failure Requiring Invasive Mechanical Ventilation. Time Frame: From Baseline through Day 7	Number of participants who develop respiratory failure requiring initiation of invasive mechanical ventilation, assessed by clinical criteria and the requirement for endotracheal intubation and invasive mechanical ventilation.	From Baseline through Day 7
Diaphragmatic Excursion Measured by Point of Care ultrasound Time Frame: Baseline, 24 hours, 48 hours, and 72 hours	Diaphragmatic Excursion measured using M mode point of care ultrasound during spontaneous breathing or ventilator supported breathing, as applicable and measured in millimeter. Three measurements will be obtained and averaged.	Baseline, 24 hours, 48 hours, and 72 hours
Diaphragmatic Thickness Measured by Point of Care Ultrasound Time Frame: Baseline, 24 hours, 48 hours, and 72 hours	Diaphragmatic thickness measured at the zone of apposition using B mode point of care ultrasound at end expiration and measured in millimeter. Three measurements will be obtained and averaged.	Baseline, 24 hours, 48 hours, and 72 hours
Diaphragmatic Thickening Fraction Measured by Point of Care Ultrasound Time Frame: Baseline, 24 hours, 48 hours, and 72 hours	Diaphragmatic thickening fraction measured using point of care ultrasound and calculated as [(inspiratory thickness-expiratory thickness) / expiratory thickness] * 100 and measured in percentage. Three measurements will be obtained and averaged.	Baseline, 24 hours, 48 hours, and 72 hours

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
Time to Initiation of Invasive Mechanical Ventilation Time Frame: From baseline through Day 7	Time from study enrollment to initiation of invasive mechanical ventilation, measured in hours	From baseline through Day 7
Duration of invasive mechanical ventilation Time Frame: From initiation of invasive mechanical ventilation until successful discontinuation of invasive mechanical ventilation, assessed through ICU discharge or up to 28 days, whichever comes first.	Duration of invasive mechanical ventilation, calculated from the initiation of invasive mechanical ventilation until successful discontinuation of mechanical ventilation, measured in days.	From initiation of invasive mechanical ventilation until successful discontinuation of invasive mechanical ventilation, assessed through ICU discharge or up to 28 days, whichever comes first.
Number of Participants with Weaning failure Time Frame: From the first spontaneous breathing trial until successful liberation from invasive mechanical ventilation or ICU discharge, assessed up to 28 days.	Number of participants who fail the initial attempt to discontinue invasive mechanical ventilation according to predefined clinical criteria and subsequently require continuation or resumption of mechanical ventilatory support.	From the first spontaneous breathing trial until successful liberation from invasive mechanical ventilation or ICU discharge, assessed up to 28 days.
Number of Participants With Extubation failure Time Frame: within 72 hours after extubation.	Number of participants requiring reintubation and reinstitution of invasive mechanical ventilation following planned extubation.	within 72 hours after extubation.
Duration of Intensive Care Unit stay Time Frame: From baseline (ICU admission) until ICU discharge or death, assessed up to 28 days.	Duration of stay in the intensive care unit from ICU admission until ICU discharge, measured in days.	From baseline (ICU admission) until ICU discharge or death, assessed up to 28 days.
Number of Participants Who Die During Intensive Care Unit Stay Time Frame: From baseline (ICU admission) until ICU discharge or death, assessed up to 28 days.	Number of participants who die during the Intensive Care Unit stay	From baseline (ICU admission) until ICU discharge or death, assessed up to 28 days.

Collaborators and Investigators

This is where you will find people and organizations involved with this study.

Sponsor

Assiut University

Investigators

Study Director: Refaat Fathy Abdelaal, professor, Assiut University
Study Director: Dina Ali Ahmed, doctor, Assiut University

Publications and helpful links

The person responsible for entering information about the study voluntarily provides these publications. These may be about anything related to the study.

General Publications

Study record dates

These dates track the progress of study record and summary results submissions to ClinicalTrials.gov. Study records and reported results are reviewed by the National Library of Medicine (NLM) to make sure they meet specific quality control standards before being posted on the public website.

Study Major Dates

Study Start (Estimated)

October 1, 2026

Primary Completion (Estimated)

March 15, 2028

Study Completion (Estimated)

June 1, 2028

Study Registration Dates

First Submitted

September 4, 2026

First Submitted That Met QC Criteria

September 11, 2026

First Posted (Actual)

September 15, 2026

Study Record Updates

Last Update Posted (Actual)