NCT03811158.

Study name	The diaphragm activity level and cardiopulmonary function between heated humidified high‐flow nasal cannula and unheated humidified high‐flow oxygen mask in acute exacerbation of COPD patients as post‐extubation respiratory support
Methods	RCT, cross‐over design. Single‐centre. No details of cross‐over
Participants	Estimated number of participants: 20 Setting: ICU, Taiwan Inclusion criteria: AECOPD; intubated and ready for weaning; PaO2/FiO2 > 200 during SBT Exclusion criteria: unable to insert NG; refused reintubation; planned NIV post‐extubation; pregnancy
Interventions	Intervention group (HFNC) Control group (standard oxygen therapy): unheated humidified high‐flow oxygen mask
Outcomes	All outcomes reported: diaphragm electrical activity; transcutaneous pulse oxymetry and capnography; reintubation rate; cardiac index; hospital length of stay; ICU length of stay Outcomes relevant to this review: pulse oxymetry; reintubation rate; hospital length of stay
Starting date	22 January 2019
Contact information	Ke‐Yun Chao, ck_qq@hotmail.com
Notes	Need to assess flow rate in the control group to determine eligibility