General AnesthesiaBREATHSOUNDNCT07280546
Analysis of Breath Sounds During Surgery
An observational study of General Anesthesia and Intraoperative Monitoring, run by Taipei Veterans General Hospital, Taiwan at 1 site in Taiwan.
Trial summary
This study aims to analyze breath sounds during surgery by using electronic stethoscope sensors attached to patients under general anesthesia. The study will evaluate whether breath sound monitoring can provide useful information for respiratory management, assist anesthesiologists in early detection of abnormal… Read more about this study
- Who is it for?
- Ages 20 years and older
- Conditions the study is for
- General Anesthesia, Intraoperative Monitoring, Respiratory Sounds
- What is being tested?
- Electronic stethoscope monitoring
- How many people
- 30 participants
- Where
- 1 siteTaiwan
- Study dates
- 3 Sep 2025to 30 Sep 2026
- Phase
- Observational
- Are there results?
- Not yet: the study is under way
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 20 years and older
- All sexes
- No healthy volunteers
- Adult, Older adult
Study population: Adult surgical patients (aged 20 years or older) scheduled for elective surgery under general anesthesia at Taipei Veterans General Hospital, Taiwan. Eligible patients are ASA I-III and willing to provide informed consent. Patients with significant respiratory disease or airway abnormalities will be excluded.
Who may be able to join
- Age ≥ 20 years
- American Society of Anesthesiologists (ASA) physical status I-III
- Scheduled for elective surgery under general anesthesia
- Provided written informed consent
Who cannot join
- History of respiratory disease (e.g., COPD, severe asthma)
- Previous airway surgery or anatomical abnormalities that interfere with breath sound assessment
- Refusal to participate or inability to comply with study procedures
Trial locations and contacts
1 site in 1 country. Contact the study team or a site near you to ask about taking part.
Taiwan1 site, 1 recruiting
- Recruiting
Department of Anesthesiology, Taipei Veterans General Hospital
Taipei, 11217
About this study
This study aims to analyze breath sounds during surgery by using electronic stethoscope sensors attached to patients under general anesthesia. The study will evaluate whether breath sound monitoring can provide useful information for respiratory management, assist anesthesiologists in early detection of abnormal breathing events, and support safer perioperative care. A total of 30 adult patients undergoing elective surgery under general anesthesia will be enrolled.
Read the detailed description
Continuous breath sound monitoring has the potential to provide anesthesiologists with real-time physiological information that is not captured by standard perioperative monitors. During general anesthesia, subtle changes in airflow or airway patency may precede clinically apparent respiratory compromise. Traditional auscultation is intermittent, subjective, and dependent on the operator's experience. Recent advances in electronic stethoscope technology enable continuous, high-fidelity acquisition of breath sound signals, allowing quantitative analysis and automated detection of abnormal respiratory patterns.
In this prospective observational study, adult patients undergoing elective surgery under general anesthesia will have electronic stethoscope sensors placed on the anterior chest wall prior to induction. Breath sound signals will be continuously recorded throughout anesthesia and surgery. Signal acquisition parameters (sampling rate, filtering, and sensor placement) will be standardized across participants. All breath sound recordings will be synchronized with standard intraoperative monitoring data, including respiratory rate, tidal volume, capnography, pulse oximetry, and hemodynamic parameters. The synchronized dataset will allow temporal correlation between acoustic features and clinically documented respiratory events.
Collected signals will undergo post-processing to extract quantitative acoustic features such as amplitude, frequency distribution, airflow-related patterns, and event-associated spectral changes. Episodes suggestive of abnormal respiration-such as diminished breath sounds, irregular airflow patterns, obstruction-like signatures, or apnea-like silent periods-will be identified and compared with clinical observations recorded by anesthesia providers. The study will also evaluate the feasibility of integrating continuous breath sound information into perioperative workflows, including the practicality of sensor placement, stability of recordings during surgical manipulation, and compatibility with existing monitoring systems.
The overall goal of the study is to generate foundational evidence on the technical feasibility and clinical relevance of continuous breath sound monitoring under general anesthesia. Findings from this study may support future development of automated respiratory event detection tools and may contribute to safer perioperative respiratory management.
- Being tested
- Electronic stethoscope monitoring
- Keywords
- Breath sounds, Perioperative care, Airway monitoring, Respiratory complications, Double-lumen endotracheal tube (DLT)
- Medical subject headings
- Respiratory Sounds
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Electronic stethoscope monitoringOther
Application of electronic stethoscope patches on the patient's chest during surgery to record breath sounds for subsequent analysis. No therapeutic intervention is given; this is a monitoring/observational tool.
| Study group | Role | What they receive |
|---|---|---|
| Observation Group | Patients undergoing elective surgery under general anesthesia with endotracheal intubation. Electronic stethoscope patches will be placed to record and analyze intraoperative breath sounds. Target enrollment: 30 participants. Receives: Other: Electronic stethoscope monitoring |
What is being measured
The primary outcome is the main question the study is designed to answer.
Accuracy of electronic breath sound monitoring during surgery
Assessment will be based on the proportion of intraoperative respiratory events correctly identified by the electronic breath sound monitoring system compared with standard clinical assessment.
Measured: During surgery (from induction of anesthesia until emergence)
Secondary outcomes (3)
Incidence of respiratory events detected by the device
Number of intraoperative respiratory events (e.g., hypoventilation, airway obstruction, disconnection) identified by the monitoring system.
Measured: Intraoperative period.
Correlation between electronic breath sound monitoring and clinical observation
Correlation (r-value) between device output and anesthesiologist-documented respiratory findings.
Measured: Intraoperative period.
User feasibility and device performance
Feasibility will be assessed by reporting the proportion of cases in which continuous breath sound monitoring was successfully completed without interruption, including documentation of signal quality issues and workflow interference if present. (No rating scale will be used.)
Measured: Immediately after surgery (postoperative evaluation).
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted12 Dec 2025
- Study start3 Sep 2025
- Primary completion28 Feb 2026 (estimated)
- Study completion30 Sep 2026 (estimated)
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Publications (3)Papers the sponsor has linked to this study.
- Other trials for General AnesthesiaStudies of the same condition, open and under way.
- More trials run by Taipei Veterans General Hospital, TaiwanThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Observational
- Observational model
- Cohort
- Time perspective
- Prospective
- Enrolment
- 30 participants (estimated)
Sponsor and investigators
- Lead sponsor
- Taipei Veterans General Hospital, Taiwan
- Sponsor type
- Other government
- Responsible party
- Sponsor
- Investigators
- Hui-Hsuan Ke, MD, Principal investigator, Taipei Veterans General Hospital, Taiwan
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT07280546
- Sponsor's protocol ID
- 2022-09-002AC
- Acronym
- BREATHSOUND
- Status last verified
- Dec 2025
- First submitted
- 17 Sep 2025
- Last updated
- 12 Dec 2025
- Results posted
- No
- Data monitoring committee
- No
- FDA-regulated drug
- No
- FDA-regulated device
- No
- Individual data sharing
- Yes: De-identified breath sound recordings and corresponding clinical parameters (e.g., age, ASA physical status, type of anesthesia) will be shared.
Publications
Manecke GR Jr, Dilger JP, Kutner LJ, Poppers PJ. Auscultation revisited: the waveform and spectral characteristics of breath sounds during general anesthesia. Int J Clin Monit Comput. 1997 Nov;14(4):231-40. doi: 10.1007/BF03356568.
PubMed 9451573Mansy HA, O'Connor CJ, Balk RA, Sandler RH. Breath sound changes associated with malpositioned endotracheal tubes. Med Biol Eng Comput. 2005 Mar;43(2):206-11. doi: 10.1007/BF02345956.
PubMed 15865129Wei TJ, Hsiung PY, Liu JH, Lin TC, Kuo FT, Wu CY. Use of Electronic Auscultation in Full Personal Protective Equipment to Detect Ventilation Status in Selective Lung Ventilation: A Randomized Controlled Trial. Front Med (Lausanne). 2022 Feb 21;9:851395. doi: 10.3389/fmed.2022.851395. eCollection 2022.
PubMed 35265648
Study at a glance
From the registry record, last updated by the sponsor on 12 Dec 2025. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Analysis of Breath Sounds During Surgery
- ClinicalTrials.gov ID
- NCT07280546
- Acronym / sponsor ID
- BREATHSOUND / 2022-09-002AC
- Keywords
- Breath sounds, Perioperative care, Airway monitoring, Respiratory complications, Double-lumen endotracheal tube (DLT)
- Study type
- Observational
- Recruitment status
- Recruiting
- Enrolment
- 30 participants (estimated)
- Lead sponsor
- Taipei Veterans General Hospital, TaiwanOther government
- Study start
- 3 Sep 2025 (actual)
- Primary completion
- 28 Feb 2026 (estimated)
- Study completion
- 30 Sep 2026 (estimated)
- First posted
- 12 Dec 2025 (actual)
- Results
- Not posted in the source record
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
This study aims to analyze breath sounds during surgery by using electronic stethoscope sensors attached to patients under general anesthesia. The study will evaluate whether breath sound monitoring can provide useful information for respiratory management, assist anesthesiologists in early detection of abnormal breathing events, and support safer perioperative care. A total of 30 adult patients undergoing elective surgery under general anesthesia will be enrolled.
Detailed description
Continuous breath sound monitoring has the potential to provide anesthesiologists with real-time physiological information that is not captured by standard perioperative monitors. During general anesthesia, subtle changes in airflow or airway patency may precede clinically apparent respiratory compromise. Traditional auscultation is intermittent, subjective, and dependent on the operator's experience. Recent advances in electronic stethoscope technology enable continuous, high-fidelity acquisition of breath sound signals, allowing quantitative analysis and automated detection of abnormal respiratory patterns.
In this prospective observational study, adult patients undergoing elective surgery under general anesthesia will have electronic stethoscope sensors placed on the anterior chest wall prior to induction. Breath sound signals will be continuously recorded throughout anesthesia and surgery. Signal acquisition parameters (sampling rate, filtering, and sensor placement) will be standardized across participants. All breath sound recordings will be synchronized with standard intraoperative monitoring data, including respiratory rate, tidal volume, capnography, pulse oximetry, and hemodynamic parameters. The synchronized dataset will allow temporal correlation between acoustic features and clinically documented respiratory events.
Collected signals will undergo post-processing to extract quantitative acoustic features such as amplitude, frequency distribution, airflow-related patterns, and event-associated spectral changes. Episodes suggestive of abnormal respiration-such as diminished breath sounds, irregular airflow patterns, obstruction-like signatures, or apnea-like silent periods-will be identified and compared with clinical observations recorded by anesthesia providers. The study will also evaluate the feasibility of integrating continuous breath sound information into perioperative workflows, including the practicality of sensor placement, stability of recordings during surgical manipulation, and compatibility with existing monitoring systems.
The overall goal of the study is to generate foundational evidence on the technical feasibility and clinical relevance of continuous breath sound monitoring under general anesthesia. Findings from this study may support future development of automated respiratory event detection tools and may contribute to safer perioperative respiratory management.
Study design
- Observational model
- Cohort
- Time perspective
- Prospective
- Number of arms
- 1
| Arm | Type | Receives |
|---|---|---|
| Observation Group | – | Other: Electronic stethoscope monitoringPatients undergoing elective surgery under general anesthesia with endotracheal intubation. Electronic stethoscope patches will be placed to record and analyze intraoperative breath sounds. Target enrollment: 30 participants. |
Who may qualify
- Ages
- 20 years and older
- Sex
- All
- Healthy volunteers
- Not accepted
- Age groups
- Adult, Older adult
- Study population
- Adult surgical patients (aged 20 years or older) scheduled for elective surgery under general anesthesia at Taipei Veterans General Hospital, Taiwan. Eligible patients are ASA I-III and willing to provide informed consent. Patients with significant respiratory disease or airway abnormalities will be excluded.
Key inclusion criteria (4 listed)
- Age ≥ 20 years
- American Society of Anesthesiologists (ASA) physical status I-III
- Scheduled for elective surgery under general anesthesia
- Provided written informed consent
Key exclusion criteria (3 listed)
- History of respiratory disease (e.g., COPD, severe asthma)
- Previous airway surgery or anatomical abnormalities that interfere with breath sound assessment
- Refusal to participate or inability to comply with study procedures
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Electronic stethoscope monitoringApplication of electronic stethoscope patches on the patient's chest during surgery to record breath sounds for subsequent analysis. No therapeutic intervention is given; this is a monitoring/observational tool. | Other | Observation Group |
Primary outcome
Accuracy of electronic breath sound monitoring during surgery
Time frame: During surgery (from induction of anesthesia until emergence)
Assessment will be based on the proportion of intraoperative respiratory events correctly identified by the electronic breath sound monitoring system compared with standard clinical assessment.
3 secondary outcomes
Incidence of respiratory events detected by the device
Time frame: Intraoperative period.
Correlation between electronic breath sound monitoring and clinical observation
Time frame: Intraoperative period.
User feasibility and device performance
Time frame: Immediately after surgery (postoperative evaluation).
Results and safety
This study is still under way. Results are not available in the source record yet.
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 12 Dec 2025.
- Background: PubMed 9451573Manecke GR Jr, Dilger JP, Kutner LJ, Poppers PJ. Auscultation revisited: the waveform and spectral characteristics of breath sounds during general anesthesia. Int J Clin Monit Comput. 1997 Nov;14(4):231-40. doi: 10.1007/BF03356568.
- Background: PubMed 15865129Mansy HA, O'Connor CJ, Balk RA, Sandler RH. Breath sound changes associated with malpositioned endotracheal tubes. Med Biol Eng Comput. 2005 Mar;43(2):206-11. doi: 10.1007/BF02345956.
- Background: PubMed 35265648Wei TJ, Hsiung PY, Liu JH, Lin TC, Kuo FT, Wu CY. Use of Electronic Auscultation in Full Personal Protective Equipment to Detect Ventilation Status in Selective Lung Ventilation: A Randomized Controlled Trial. Front Med (Lausanne). 2022 Feb 21;9:851395. doi: 10.3389/fmed.2022.851395. eCollection 2022.
- Institutional Review Board of Taipei Veterans General HospitalLink provided by the sponsor.
- Frontiers in Medicine - Electronic Auscultation TrialLink provided by the sponsor.
- Individual participant dataSharing planned: Yes. De-identified breath sound recordings and corresponding clinical parameters (e.g., age, ASA physical status, type of anesthesia) will be shared.
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part.
Hui-Hsuan Ke, MD principal investigator
Taipei Veterans General Hospital, Taiwan
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
An observational study of General Anesthesia and Intraoperative Monitoring, run by Taipei Veterans General Hospital, Taiwan at 1 site in Taiwan.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 4 inclusion and 3 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: looking for participants now, as of the sponsor's last update on 12 Dec 2025. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in Taiwan. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
Are results available for this study?
This study is still under way. Results are not available in the source record yet.
How can a doctor refer a patient or contact the research team?
Contact Hui-Hsuan Ke, MD (-886-939-196-809, kehuihsuan0221@gmail.com), or a site near the patient. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
Accuracy of electronic breath sound monitoring during surgery (time frame: During surgery (from induction of anesthesia until emergence)). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT07280546, which also lists 3 linked publications.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 12 Dec 2025.