Related Experiment Video
Updated: May 23, 2026

Inspiratory Muscle Training as an Adjunct to the Treatment of Weaning Failure in Critically Ill Patients: A Practical Guide
Published on: January 30, 2026
Randomised weaning trial comparing assist control to pressure support ventilation
Deena Shefali-Patel1, Vadivelam Murthy, Simon Hannam
1Division of Asthma, Allergy and Lung Biology, Kings College London, London, UK.
Objectives:
To determine if the work of breathing was lower, respiratory muscle strength greater, but the degree of asynchrony higher during weaning by assist control ventilation (ACV) rather than pressure support ventilation (PSV) and if any differences were associated with a shorter duration of weaning.
Design:
Randomised trial
Setting:
Tertiary neonatal unit
Patients:
Thirty-six infants, median gestational age 29 (range 24 to 39) weeks
Intervention:
Weaning by either ACV or PSV.
Main Outcome Measures:
At baseline, 24 hours after entering the study and immediately prior to extubation, the work of breathing (PTPdi), thoracoabdominal asynchrony (TAA) and respiratory muscle strength (Pimax) were assessed and weaning duration recorded.
Results:
There were no significant differences in the median PTPdi, TAA and Pimax results at any time point. The inflation times during ACV and PSV were similar. The median duration of weaning was 34 (range 7-100) hours in the ACV group and 27 (range 10-169) hours in the PSV group (p=0.88).
Conclusion:
No significant differences were found between weaning by PSV and ACV when similar inflation times were used.
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