Evaluation of Diaphragmatic Dysfunction in Mechanically Ventilated Critically Ill Subjects

Area of Science:

• Critical Care Medicine
• Pulmonology
• Diagnostic Imaging

Background:

• Diaphragmatic dysfunction (DD) is a potential complication in critically ill patients requiring invasive mechanical ventilation.
• Understanding the prevalence and predictors of DD is crucial for optimizing patient care and ventilator management.

Purpose of the Study:

• To evaluate the prevalence and associated factors of diaphragmatic dysfunction using bedside ultrasound.
• To assess diaphragm excursion (DE) and thickening fraction (TF) in mechanically ventilated patients.

Main Methods:

• A cross-sectional study of 56 ICU patients on pressure-support ventilation (PSV) for at least 24 hours.
• Bedside ultrasound was used to measure diaphragm excursion (DE) and thickening fraction (TF).
• Poisson regression analysis identified factors associated with DD, defined by specific DE and TF criteria.

Main Results:

• Diaphragmatic dysfunction was prevalent, with 37.5% showing reduced DE and 57.1% abnormal TF.
• Reduced DE was linked to neoplastic disease, lower tidal volume, superficial sedation, and longer intubation duration.
• Abnormal TF was associated with cardiovascular disease, elevated heart rate, and longer ICU stay.

Conclusions:

• Diaphragmatic dysfunction is common in invasively ventilated patients, with varying predictors based on ultrasound parameters.
• Bedside ultrasound is a valuable, noninvasive tool for identifying DD in the ICU.
• Ultrasound findings can guide the optimization of ventilatory strategies for critically ill patients.