Critical Illness Myopathy, Critical Illness Polyneuropathy, ICU-acquired Weakness
Conditions
Keywords
Shear Wave Elastography, Peripheral Nerve, Ultrasonography, Critical Care, Early Diagnosis
Brief summary
This study aims to determine whether shear wave elastography (SWE), a non-invasive ultrasound technique that measures nerve stiffness, can help detect ICU-acquired weakness (ICU-AW) early in critically ill patients. Adults receiving mechanical ventilation in the ICU will undergo ultrasound examinations of the median and tibial nerves on Days 1, 4, and 7. The study will evaluate whether early changes in nerve elasticity can predict ICU-AW, which is usually diagnosed later using a muscle strength score that requires patient cooperation.
Detailed description
Intensive Care Unit-Acquired Weakness (ICU-AW) is a common and severe complication in critically ill patients, associated with poor long-term outcomes. The current gold standard for diagnosis, the Medical Research Council (MRC) score, requires patient cooperation and is often delayed. Shear Wave Elastography (SWE) is an advanced ultrasound technique that quantitatively measures tissue stiffness. Pathophysiological changes in ICU-AW, such as axonal degeneration and edema in nerves, are expected to alter their biomechanical properties (elasticity). This study posits that these changes may be detectable early using SWE, preceding overt clinical weakness. This study will prospectively enroll adult patients admitted to the ICU who are expected to require prolonged mechanical ventilation. Participants will undergo serial ultrasound examinations of the median and tibial nerves on days 1, 4, and 7 of their ICU stay. The examinations will include SWE to measure nerve elasticity (stiffness) and conventional B-mode ultrasound to measure nerve cross-sectional area (CSA). On day 7, all consenting and cooperative patients will be assessed for ICU-AW using the MRC score. The primary objective is to determine the diagnostic accuracy of early nerve SWE measurements for predicting the diagnosis of ICU-AW on Day 7. Secondary objectives include describing the dynamic changes in nerve elasticity and size over the first week, and exploring the correlation between these ultrasound parameters and clinical severity scores and patient outcomes.
Interventions
DIAGNOSTIC_TESTNerve Ultrasound with Shear Wave Elastography
Patients will undergo non-invasive ultrasound examinations of the median nerve and tibial nerve at the bedside on days 1, 4, and 7. The examination includes Shear Wave Elastography (SWE) to quantify nerve stiffness (elasticity) and B-mode imaging to measure nerve cross-sectional area (CSA). This is a purely observational procedure and does not alter patient management.
Sponsors
First Affiliated Hospital of Wannan Medical College
Study design
Observational model
COHORT
Time perspective
PROSPECTIVE
Eligibility
Sex/Gender
ALL
Age
18 Years to 85 Years
Healthy volunteers
No
Inclusion criteria
1. Age ≥ 18 years; 2. Newly admitted to ICU with an expected ICU stay \> 7 days; 3. Initiated on mechanical ventilation within 24 hours of admission, with an expected ventilation duration \> 48 hours; 4. Patient or legally authorized representative provides written informed consent.
Exclusion criteria
1. Known pre-existing neuromuscular diseases (e.g., myasthenia gravis, Guillain-Barré syndrome, amyotrophic lateral sclerosis); 2. Pre-existing limb dysfunction that would interfere with muscle strength assessment (e.g., hemiplegia, paraplegia, severe arthritis); 3. Presence of acute trauma, surgery, skin breakdown, infection, or severe edema at the measurement sites (wrist, elbow, ankle) that would interfere with ultrasound probe placement; 4. Pregnant or lactating women; 5. Any other condition that the investigator believes would make the patient unsuitable for the study.
Design outcomes
Primary
| Measure | Time frame | Description |
|---|---|---|
| Diagnostic Accuracy of Nerve SWE on Day 1 for Predicting ICU-AW on Day 7 | Day 1 and Day 7 after ICU admission | Area Under the Receiver Operating Characteristic Curve (AUC) for the mean elasticity value (measured in kilopascals, kPa) of the median and tibial nerves, assessed separately at three time points after ICU admission: Day 1 - to predict ICU-AW diagnosed on Day 7 Day 7 - for concurrent diagnosis of ICU-AW (elastography and MRC assessed independently, blinded to each other) ICU-Acquired Weakness (ICU-AW) is defined as a Medical Research Council (MRC) sum score of less than 48 points. |
| Diagnostic Accuracy of Nerve SWE on Day 4 for Predicting ICU-AW on Day 7 | Day 4 and Day 7 after ICU admission | Area Under the Receiver Operating Characteristic Curve (AUC) for the mean elasticity value (measured in kilopascals, kPa) of the median and tibial nerves, assessed separately at three time points after ICU admission: Day 4 - to predict ICU-AW diagnosed on Day 7 Day 7 - for concurrent diagnosis of ICU-AW (elastography and MRC assessed independently, blinded to each other) ICU-Acquired Weakness (ICU-AW) is defined as a Medical Research Council (MRC) sum score of less than 48 points. |
| Diagnostic Accuracy of Nerve SWE on Day 7 for Diagnosing ICU-AW on Day 7 | Day 7 after ICU admission | Area Under the Receiver Operating Characteristic Curve (AUC) for the mean elasticity value (measured in kilopascals, kPa) of the median and tibial nerves, assessed separately at three time points after ICU admission: Day 7 - for concurrent diagnosis of ICU-AW (elastography and MRC assessed independently, blinded to each other) ICU-Acquired Weakness (ICU-AW) is defined as a Medical Research Council (MRC) sum score of less than 48 points. |
Secondary
| Measure | Time frame | Description |
|---|---|---|
| Change in Nerve Elasticity | Day 1 to Day 7 after ICU admission | Absolute and relative change in the shear wave elastography (SWE) value (in kPa) of the median and tibial nerves from baseline (Day 1) to Day 7. |
| Correlation between Nerve Elasticity and Disease Severity | Day 7 | Spearman's correlation coefficient will be calculated to assess the relationship between the baseline (Day 7) nerve SWE values and the baseline Sequential Organ Failure Assessment (SOFA) score. |
Countries
China
Contacts
CONTACTqiancheng xu, PhD
Outcome results
None listed