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Updated: Dec 31, 2025

Author Spotlight: Unraveling the Impact of Mechanical Ventilation on Diaphragm Function and Patient Outcomes
Published on: November 3, 2023
Sonographically Measured Improvement in Diaphragmatic Mobility and Outcomes Among Patients Requiring Prolonged
N Gibis1, A Schulz1, S Vonderbank1
1Marienkrankenhaus Kassel, Marburger Str. 85, 34127 Kassel, Germany.
Background:
The need of prolonged weaning from the ventilator is a well-known predictor of an unfavorable patients` outcome. Diaphragmatic dysfunction is a serious problem for these patients. We wanted to determine the survival in patients who were already intubated for more than 4 weeks before they were admitted to our weaning unit. In this prospective study, we wanted to investigate if the diaphragmatic function could improve or was related to survival over an 18 months follow up period.
Methods:
84 patients were included when they were able to breathe at least 10 minutes over a t-piece and sit upright for at least 5 minutes. The diaphragmatic function was estimated sonographically using the up and downward movement of the lung silhouette. Sonographic follow-ups were performed for over 18 months. The survival rate, outcome and changes in diaphragm mobility were investigated.
Results:
a) Survival: 49 patients (58%) survived the 18 months follow up period - 30 had a good outcome; 19 needed assistance. b) Survival in relation to diaphragm mobility: If diaphragmatic mobility improved ≥ 15.5 mm on the left side, the probability of survival was 94% with a probability of 76% to have a satisfying outcome.
Conclusion:
Survival and outcome of prolonged weaning were significantly better when sonographically measured the mobility of left hemidiaphragm improved.
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