Diaphragmatic Physiology Similarity Index May Titrate HFNC Flow Setting: A Prospective Observational Study
Trial Parameters
Brief Summary
Study Objective This prospective observational study aims to investigate the role of the Diaphragmatic Physiology Similarity Index (DPSI) derived from speckle tracking ultrasound in titrating high-flow nasal cannula (HFNC) flow settings, and to evaluate its application in patients with acute respiratory failure. Primary Research Questions To characterize the features of the DPSI in healthy individuals and in patients with acute respiratory failure. To assess the behavior of the DPSI under different HFNC flow settings in patients with acute respiratory failure. Secondary Research Questions Feasibility and inter-operator reproducibility of diaphragmatic speckle tracking. Assessment of the Diaphragmatic Contraction Synchrony Index. Evaluation of End-Diaphragmatic Residual Contraction (EDRC). Additional fundamental parameters, including diaphragmatic displacement velocity and maximum displacement.
Eligibility Criteria
Feasibility and reproducibility：adult ICU patients Methodology for diaphragmatic motion synchrony:healthy adults and adult ICU patients Between-group comparisons and flow-titration study Inclusion Criteria: 1. Age ≥18 years old. 2. Clear diagnosis of respiratory failure requiring respiratory support. 3. Expected duration of respiratory support ≥24 hours or (high-flow/non-invasive ventilation) ≥48 hours. 4. Voluntary participation in this study and signed informed consent. If the participant is unable to read or sign the informed consent form due to incapacity (e.g., unconsciousness), the legal guardian must act as a proxy in the informed consent process and sign the form. If the participant cannot read the consent form (e.g., illiterate participants), a witness must observe the informed consent process and sign the form. Exclusion Criteria: 1. Severe chest wall deformities or diaphragmatic paralysis. 2. End-stage disease with a predicted life expectancy of less than 24 hours. 3. Inabil