High-frequency chest wall oscillation in prolonged mechanical ventilation patients: a randomized controlled trial
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Updated: Apr 24, 2026

Monitoring Lung Function with Electrical Impedance Tomography in the Intensive Care Unit
Published on: September 6, 2024
Wei-Chang Huang1,2, Pi-Chu Wu3, Chao-Jung Chen3
1Division of Respiratory and Critical Care Medicine, Department of Internal Medicine, Taichung Veterans General Hospital, Taichung, Taiwan.
Background And Aims:
Patients with prolonged mechanical ventilation (PMV) often retain airway secretions, which may be cleared with the assistance of high-frequency chest wall oscillation (HFCWO). This study aimed to determine the effectiveness, safety and tolerance/comfort of HFCWO after extubation in PMV patients.
Methods:
This parallel-designed, randomized controlled trial enrolled subjects with both intra-tracheal intubation and mechanical ventilator support continuously for at least 21 days between January 2011 and December 2012. Upon extubation, the participants were randomly assigned to either receive HFCWO for 5 days or not. The effectiveness [based on weaning success rates, daily clearance volume of sputum, serial changes in sputum coloration and chest X-ray (CXR) improvement rates], safety (by physiologic parameters) and tolerance/comfort [using the Modified Borg Scale (MBS) and Hamilton Anxiety Scale (HAS)] of HFCWO were investigated.
Results:
There were 43 PMV subjects, including 23 in the HFCWO group and 20 in the non-HFCWO group. The weaning success rates were 82.6% (19/23) and 85% (17/20) in the HFCWO and non-HFCWO groups, respectively (P = 1.000). The HFCWO group had persistently greater numbers of daily sputum suctions and higher CXR improvement rates compared with the non-HFCWO group. There was significant sputum coloration lightening in the HFCWO group only. There was no significant difference in the MBS and HAS between the two groups and between pre- and post-HFCWO physiologic parameters.
Conclusion:
In PMV patients, HFCWO was safe, comfortable and effective in facilitating airway hygiene after removal of endotracheal tubes, but had no positive impact on weaning success.
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