This preprint is under consideration at BMC Sports Science, Medicine and Rehabilitation. A preprint is a preliminary version of a manuscript that has not completed peer review at a journal. Research Square does not conduct peer review prior to posting preprints. The posting of a preprint on this server should not be interpreted as an endorsement of its validity or suitability for dissemination as established information or for guiding clinical practice.
Learn more about In Review
A new preprint design is coming!
We have improved readability, clarity, accessibility, and opportunities for engagement.
Research article
Andreas Fichtner
University Hospital Carl Gustav Carus
Corresponding Author
License:
This work is licensed under a CC BY 4.0 License. Read Full License
Background
Observing modern decompression protocols alone cannot fully prevent Diving Accidents especially in repetitive diving. Audio Doppler bubble measurements to estimate supersaturation are done in special professional settings only, being not available for the broad community of sports SCUBA divers. In case SCUBA divers without medical and ultrasound training could learn audio Doppler self-assessment for reliable bubble grading on a stable skill level and with an efficient single teaching intervention, this skill could add significantly to diving safety.
Methods
We taught audio Doppler self-assessment of the subclavian vein and cardiac precordial probe position to 41 divers in a 45-minute standardized training session. Assessment was made of 684 audio Doppler measurements by both the trained divers and a medical professional plus additional 2D-echocardiography as reference.
Results
All air dives were within normal sports diving limits and decompression bubbles were observable via echocardiography in 32.3% of all measurements. The specificity of audio bubble detection was 96.1% but the sensitivity was low for lower bubble grades, increasing to 25%, 35% and 67% for higher echo-detected bubble grades 3, 4 and 5. The number of attempts to achieve a reliable venous signal within 30 seconds was 13 at the subclavian position and 18 at the precordial position. More bubble positive measurements could be detected at the precordial position for both self and medical professional assessment. The performance level of the taught skill remained stable over six months without further practice.
Conclusion
Audio Doppler self-assessment can be learned by people without medical and ultrasound training and a reliable venous signal can be achieved after a comparably steep learning curve. However, accurate bubble grading is not possible using audio Doppler as only higher bubble grades can be detected. Nevertheless, this qualitative finding can be important in self-evaluating decompression stress and potentially help the diver to judge on measures for avoiding decompression accidents.
Keywords
Doppler ultrasound, decompression, scuba diving, self-monitoring
Figure 1
Figure 2
Figure 3
Figure 4
Figure 5
Figure 6
This is a list of supplementary files associated with this preprint. Click to download.
- FichtnerTab1.jpg
Table 1: Spencer and Eftedal-Brubakk scales for audio Doppler and 2D Echo bubble grading. Both are categorized and non-linear scales and Spencer Grade 4 includes an unlimited amount of bubbles equivalent to Eftedal-Brubakk Grade 5 as well.
Loading...
Badges
Prescreen
This manuscript passed our Prescreen assessment
Complete author information
Appropriate declaration statements
Potential risks to human health
Prescreen
Peer Review Timeline
CURRENT STATUS: Under Review
Version 1
Posted 29 Dec, 2020
No community comments so far
Editorial decision: Major revision
On 01 Feb, 2021
Review #2 received
Received 29 Dec, 2020
Review #1 received
Received 29 Dec, 2020
Reviewer #2 agreed
On 23 Dec, 2020
Reviewer #1 agreed
On 23 Dec, 2020
Reviewers invited
Invitations sent on 17 Dec, 2020
Editor assigned
On 15 Nov, 2020
Submission checks complete
On 15 Nov, 2020
Editor invited
On 15 Nov, 2020
First submitted
On 14 Nov, 2020
Metrics
Comments: 0
PDF Downloads: ...
HTML Views: ...
Learn more about our company.
A new preprint design is coming!
We have improved readability, clarity, accessibility, and opportunities for engagement.
This preprint is under consideration at BMC Sports Science, Medicine and Rehabilitation. A preprint is a preliminary version of a manuscript that has not completed peer review at a journal. Research Square does not conduct peer review prior to posting preprints. The posting of a preprint on this server should not be interpreted as an endorsement of its validity or suitability for dissemination as established information or for guiding clinical practice.
Learn more about In Review
Research article
Andreas Fichtner
University Hospital Carl Gustav Carus
Corresponding Author
Badges
Prescreen
This manuscript passed our Prescreen assessment
Complete author information
Appropriate declaration statements
Potential risks to human health
Prescreen
Peer Review Timeline
CURRENT STATUS: Under Review
Version 1
Posted 29 Dec, 2020
No community comments so far
Editorial decision: Major revision
On 01 Feb, 2021
Review #2 received
Received 29 Dec, 2020
Review #1 received
Received 29 Dec, 2020
Reviewer #2 agreed
On 23 Dec, 2020
Reviewer #1 agreed
On 23 Dec, 2020
Reviewers invited
Invitations sent on 17 Dec, 2020
Editor assigned
On 15 Nov, 2020
Submission checks complete
On 15 Nov, 2020
Editor invited
On 15 Nov, 2020
First submitted
On 14 Nov, 2020
Metrics
Comments: 0
PDF Downloads: ...
HTML Views: ...
License:
This work is licensed under a CC BY 4.0 License. Read Full License
Background
Observing modern decompression protocols alone cannot fully prevent Diving Accidents especially in repetitive diving. Audio Doppler bubble measurements to estimate supersaturation are done in special professional settings only, being not available for the broad community of sports SCUBA divers. In case SCUBA divers without medical and ultrasound training could learn audio Doppler self-assessment for reliable bubble grading on a stable skill level and with an efficient single teaching intervention, this skill could add significantly to diving safety.
Methods
We taught audio Doppler self-assessment of the subclavian vein and cardiac precordial probe position to 41 divers in a 45-minute standardized training session. Assessment was made of 684 audio Doppler measurements by both the trained divers and a medical professional plus additional 2D-echocardiography as reference.
Results
All air dives were within normal sports diving limits and decompression bubbles were observable via echocardiography in 32.3% of all measurements. The specificity of audio bubble detection was 96.1% but the sensitivity was low for lower bubble grades, increasing to 25%, 35% and 67% for higher echo-detected bubble grades 3, 4 and 5. The number of attempts to achieve a reliable venous signal within 30 seconds was 13 at the subclavian position and 18 at the precordial position. More bubble positive measurements could be detected at the precordial position for both self and medical professional assessment. The performance level of the taught skill remained stable over six months without further practice.
Conclusion
Audio Doppler self-assessment can be learned by people without medical and ultrasound training and a reliable venous signal can be achieved after a comparably steep learning curve. However, accurate bubble grading is not possible using audio Doppler as only higher bubble grades can be detected. Nevertheless, this qualitative finding can be important in self-evaluating decompression stress and potentially help the diver to judge on measures for avoiding decompression accidents.
Figure 1
Figure 2
Figure 3
Figure 4
Figure 5
Figure 6
This is a list of supplementary files associated with this preprint. Click to download.
- FichtnerTab1.jpg
Table 1: Spencer and Eftedal-Brubakk scales for audio Doppler and 2D Echo bubble grading. Both are categorized and non-linear scales and Spencer Grade 4 includes an unlimited amount of bubbles equivalent to Eftedal-Brubakk Grade 5 as well.
Loading...