Condition category
Respiratory
Date applied
24/09/2019
Date assigned
10/10/2019
Last edited
09/10/2019
Prospective/Retrospective
Prospectively registered
Overall trial status
Ongoing
Recruitment status
Recruiting

Plain English Summary

Background and study aims
A high-flow system is a kind of device with stable oxygen delivery performance. In clinical practice, high-flow oxygen therapy (HFOT) is widely used in the treatment of hypoxemia (low level of oxygen in the blood) caused by various reasons. A number of studies have shown that compared with standard oxygen therapy, patients with HFOT have better comfort, and the breathing rate and blood oxygenation also have a significant improvement. The beneficial effects of HFOT can be explained by its good tolerance and some physiological characteristics, which include the accurate inhaled oxygen concentration (FiO2), a certain level of positive end-expiratory pressure (PEEP) effect and continuous scour of dead cavities to reduce the CO2 levels of end-expiratory and arteries, it can also reduce the work of breathing. During nasal high-flow oxygen therapy, many studies have shown that the end-tidal lung volume can increase due to the certain level of PEEP effect, but recent studies have pointed out that in patients with brain injury who used the tracheotomy high-flow oxygen therapy (THFO), there is no PEEP effect, and on the contrary, end-tidal lung volume (non-gravity lung) decreased with the increase of flow. This may be related to the work of the patient's expiratory muscles caused by the increased resistance of the expiratory phase. Therefore, this study will further explore whether the changes of the end-tidal lung volume is related to the work of the diaphragm and some expiratory muscles during tracheotomy high-flow oxygen therapy (THFO).

Who can participate?
Patients aged 18 to 70 years old with mild to moderate respiratory distress syndrome and/or hypoxemia

What does the study involve?
Patients will be given oxygen by a conventional tracheotomy mask and tracheotomy high-flow oxygen therapy (THFO). The oxygen flow in the THFO group will be set at 30L/min, 45L/min and 60L/min, each of which lasts for 30 minutes respectively, and during the different oxygen supply modes the changes of end-tidal lung volume will be measured by electrical impedance tomography (ETI), the diaphragm and the related expiratory muscles (mainly including the transversus abdominis muscle) will be measured in the expiratory phase by ultrasound to assess the muscle work. The researchers will also pay close attention to the patient's vital signs, oxygenation and gas exchange at the same time.

What are the possible benefits and risks of participating?
High-flow oxygen therapy can provide stable inhaled oxygen concentration (FiO2) and reduce end-tidal and arterial CO2 levels, thus effectively improving patients' ventilation and oxygenation, and reducing the deterioration of the disease. Some studies have found that tracheotomy high-flow oxygen therapy can increase the successful rate of patients’ detachment from the ventilator, and at present, few reports indicate that oxygen supply by conventional tracheotomy mask and tracheotomy high-flow oxygen treatment are unacceptable, so the hazard risk is known and relatively low.

Where is the study run from?
Sir Run Run Shaw Hospital affiliated to medical college of ZheJiang University (China)

When is the study starting and how long is it expected to run for?
September 2019 to February 2020

Who is funding the study?
ZheJiang Province Education Department (China)

Who is the main contact?
Jie Ding
2233702918@qq.com

Trial website

Contact information

Type

Scientific

Primary contact

Miss Jie Ding

ORCID ID

Contact details

Sir Run Run Shaw Hospital affiliated to medical college of ZheJiang University
3 QingChun East Road
Jianggan district
HangZhou
310016
China
+86 (0)18268113280
2233702918@qq.com

Additional identifiers

EudraCT number

Nil known

ClinicalTrials.gov number

Nil known

Protocol/serial number

Y201636066

Study information

Scientific title

The relationship between the changes of the end-tidal lung volume and the work of the diaphragmatic muscle and the related respiratory muscles during tracheotomy high-flow oxygen therapy

Acronym

Study hypothesis

The end-tidal lung volume (non-gravity lung) changes with the increase of oxygen flow, and the changes may be related to the work of diaphragm and the related expiratory muscles.

Ethics approval

Approved 25/11/2016, Ethics committee of Sir Run Run Shaw Hospital affiliated to the medical college of ZheJiang University (310016; Tel: +86 (0)571 86006811), No 20161125-1

Study design

Prospective randomized cross-over study

Primary study design

Interventional

Secondary study design

Randomised cross over trial

Trial setting

Hospitals

Trial type

Treatment

Patient information sheet

Not available in web format, please use the contact details to request a patient information sheet

Condition

Patients aged 18 to 70 years old who were successfully detached from the ventilator after tracheotomy in the emergency care unit of Sir Run Run Shaw Hospital

Intervention

Patients were kept in semi-recumbent position (the bed is tilted 30-45 degrees high), and the EIT belt is used to wrap the fifth or sixth intercostal space of the patient's chest, marking the upper and lower edges of the strap to attach to the EIT. Carbon dioxide at the end of expiratory period (PECO2) was monitored by tracheal incision.
A calm environment is ensured around the patients throughout the study. Each patient undergoes four study phases in a computer-generated random order, with each phase lasting 30 min:
1. Conventional tracheotomy mask oxygen therapy, keeping the SpO2 of patients above 95%
2. THFO with gas flow at 30 l/min, keeping the SpO2 of patients above 95%
3. THFO with gas flow at 45 l/min, keeping the SpO2 of patients above 95%
4. THFO with gas flow at 60 l/min, keeping the SpO2 of patients above 95%

Ultrasound will be used to detect the changes of thickness of the diaphragmatic muscle and the related respiratory muscle at various stages, and the end-tidal lung volume will also be measured by electrical impedance tomography (ETI). Then record patients' breathing rate, heart rate, blood pressure, PECO2 and the changes of arterial blood gas at the same time. During the study, other care operations that can affect EIT, such as turning over, position replacement, etc. were all stopped.

Intervention type

Device

Phase

Not Applicable

Drug names

Primary outcome measure

Measured at the completion of each treatment with different oxygen supply modes at 30 minutes:
1. End-tidal lung volume measured using electrical impedance tomography (ETI)
2. Thickness of diaphragmatic muscle and the related respiratory muscle measured by ultrasound

Secondary outcome measures

Measured at the completion of each treatment with different oxygen supply modes at 30 minutes:
1. Respiratory rate, heart rate, blood pressure measured using patient monitor (Philips; mode: M8005A)
2. PECO2 measured by the end-of-breath carbon dioxide monitor (mode: M19042000)
3. Arterial blood gas measured by the Automatic blood gas, electrolyte and biochemical analyzer (mode: M18790600)

Overall trial start date

01/09/2019

Overall trial end date

01/02/2020

Reason abandoned (if study stopped)

Eligibility

Participant inclusion criteria

1. Aged 18 to 70 years old
2. Patients who successfully detached from the ventilator for 24 years
3. Patients with mild to moderate respiratory distress syndrome and/or hypoxemia
4. Stable vital signs

Participant type

Patient

Age group

Adult

Gender

Both

Target number of participants

50

Participant exclusion criteria

1. Hemodynamic instability (hypotension with mean arterial pressure of <60 mmHg despite volume loads or vasoactive drugs
2. Evidence of pneumothorax on chest X-ray or computed tomography scan
3. Respiratory failure explained by cardiac failure or fluid overload
4. Severe chronic obstructive pulmonary disease
5. Contraindication to electrical impedance tomography (EIT) (e.g. patients with implantable defibrillator, ETI belt positioning with wound dressing or chest drainage tube, etc)

Recruitment start date

17/10/2019

Recruitment end date

31/01/2020

Locations

Countries of recruitment

China

Trial participating centre

Sir Run Run Shaw Hospital affiliated to medical college of ZheJiang University
3 QingChun East Road Jianggan district
HangZhou
310016
China

Sponsor information

Organisation

Sir Run Run Shaw Hospital affiliated to medical college of ZheJiang University

Sponsor details

3 QingChun East Road
Jianggan district
HangZhou
310016
China
+86 (0)18268113280
2233702918@qq.com

Sponsor type

Government

Website

Funders

Funder type

Government

Funder name

Zhejiang Province Education Department

Alternative name(s)

Funding Body Type

Funding Body Subtype

Location

Results and Publications

Publication and dissemination plan

Planned publication in a high-impact peer-reviewed journal.

IPD sharing statement
The datasets generated during and/or analysed during the current study will be available upon request from Jie Ding (2233702918@qq.com) after article publication. Individual participant data that underlie the results reported in this article, after deidentification (including the changes of end-tidal lung volume and the thickness of diaphragm and the transversus abdominis muscle during different oxygen supply modes of each patient , besides, patient's vital signs, oxygenation and gas exchange will also be provided at the same time) will be shared. The data will be available beginning 9 months and ending 36 months following article publication. Anyone with any purpose who wishes to access the data is OK. The statistical analysis plan will also be available after article publication with the data. Consent from participants was obtained and data is anonymous.

Intention to publish date

01/03/2020

Participant level data

Available on request

Basic results (scientific)

Publication list

Publication citations

Additional files

Editorial Notes

08/10/2019: Trial's existence confirmed by the ethics committee of Sir Run Run Shaw Hospital affiliated to the medical college of ZheJiang University