Extreme Hypoxia Causing Brady-Arrythmias During Apnea in Elite Breath-Hold Divers
Introduction: The cardiac electrical conduction system is very sensitive to hypoglycemia and hypoxia, and the consequence may be brady-arrythmias. Weddell seals endure brady-arrythmias during their dives when desaturating to 3.2 kPa and elite breath-hold-divers (BHD), who share metabolic and cardiov...
Published in: | Frontiers in Physiology |
---|---|
Main Authors: | , , , , , , , , , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
Frontiers Media S.A.
2021
|
Subjects: | |
Online Access: | https://doi.org/10.3389/fphys.2021.712573 https://doaj.org/article/9bf5e0c58cbf41e9a56c5e2c60e08606 |
id |
ftdoajarticles:oai:doaj.org/article:9bf5e0c58cbf41e9a56c5e2c60e08606 |
---|---|
record_format |
openpolar |
spelling |
ftdoajarticles:oai:doaj.org/article:9bf5e0c58cbf41e9a56c5e2c60e08606 2023-05-15T18:43:24+02:00 Extreme Hypoxia Causing Brady-Arrythmias During Apnea in Elite Breath-Hold Divers Thomas Kjeld Anders Brenøe Isbrand Katrine Linnet Bo Zerahn Jens Højberg Egon Godthaab Hansen Lars Christian Gormsen Jacob Bejder Thomas Krag John Vissing Hans Erik Bøtker Henrik Christian Arendrup 2021-12-01T00:00:00Z https://doi.org/10.3389/fphys.2021.712573 https://doaj.org/article/9bf5e0c58cbf41e9a56c5e2c60e08606 EN eng Frontiers Media S.A. https://www.frontiersin.org/articles/10.3389/fphys.2021.712573/full https://doaj.org/toc/1664-042X 1664-042X doi:10.3389/fphys.2021.712573 https://doaj.org/article/9bf5e0c58cbf41e9a56c5e2c60e08606 Frontiers in Physiology, Vol 12 (2021) junctional rhythm brady-arrythmia free-diving invasive blood pressure hypoxia induced factor-1 (HIF-1) atrioventricular block Physiology QP1-981 article 2021 ftdoajarticles https://doi.org/10.3389/fphys.2021.712573 2022-12-31T09:20:22Z Introduction: The cardiac electrical conduction system is very sensitive to hypoglycemia and hypoxia, and the consequence may be brady-arrythmias. Weddell seals endure brady-arrythmias during their dives when desaturating to 3.2 kPa and elite breath-hold-divers (BHD), who share metabolic and cardiovascular adaptions including bradycardia with diving mammals, endure similar desaturation during maximum apnea. We hypothesized that hypoxia causes brady-arrythmias during maximum apnea in elite BHD. Hence, this study aimed to define the arterial blood glucose (Glu), peripheral saturation (SAT), heart rhythm (HR), and mean arterial blood pressure (MAP) of elite BHD during maximum apneas.Methods: HR was monitored with Direct-Current-Pads/ECG-lead-II and MAP and Glu from a radial arterial-catheter in nine BHD performing an immersed and head-down maximal static pool apnea after three warm-up apneas. SAT was monitored with a sensor on the neck of the subjects. On a separate day, a 12-lead-ECG-monitored maximum static apnea was repeated dry (n = 6).Results: During pool apnea of maximum duration (385 ± 70 s), SAT decreased from 99.6 ± 0.5 to 58.5 ± 5.5% (∼PaO2 4.8 ± 1.5 kPa, P < 0.001), while Glu increased from 5.8 ± 0.2 to 6.2 ± 0.2 mmol/l (P = 0.009). MAP increased from 103 ± 4 to 155 ± 6 mm Hg (P < 0.005). HR decreased to 46 ± 10 from 86 ± 14 beats/minute (P < 0.001). HR and MAP were unchanged after 3–4 min of apnea. During dry apnea (378 ± 31 s), HR decreased from 55 ± 4 to 40 ± 3 beats/minute (P = 0.031). Atrioventricular dissociation and junctional rhythm were observed both during pool and dry apneas.Conclusion: Our findings contrast with previous studies concluding that Glu decreases during apnea diving. We conclude during maximum apnea in elite BHD that (1) the diving reflex is maximized after 3–4 min, (2) increasing Glu may indicate lactate metabolism in accordance with our previous results, and (3) extreme hypoxia rather than hypoglycemia causes brady-arrythmias in elite BHD similar to diving mammals. Article in Journal/Newspaper Weddell Seals Directory of Open Access Journals: DOAJ Articles Weddell Frontiers in Physiology 12 |
institution |
Open Polar |
collection |
Directory of Open Access Journals: DOAJ Articles |
op_collection_id |
ftdoajarticles |
language |
English |
topic |
junctional rhythm brady-arrythmia free-diving invasive blood pressure hypoxia induced factor-1 (HIF-1) atrioventricular block Physiology QP1-981 |
spellingShingle |
junctional rhythm brady-arrythmia free-diving invasive blood pressure hypoxia induced factor-1 (HIF-1) atrioventricular block Physiology QP1-981 Thomas Kjeld Anders Brenøe Isbrand Katrine Linnet Bo Zerahn Jens Højberg Egon Godthaab Hansen Lars Christian Gormsen Jacob Bejder Thomas Krag John Vissing Hans Erik Bøtker Henrik Christian Arendrup Extreme Hypoxia Causing Brady-Arrythmias During Apnea in Elite Breath-Hold Divers |
topic_facet |
junctional rhythm brady-arrythmia free-diving invasive blood pressure hypoxia induced factor-1 (HIF-1) atrioventricular block Physiology QP1-981 |
description |
Introduction: The cardiac electrical conduction system is very sensitive to hypoglycemia and hypoxia, and the consequence may be brady-arrythmias. Weddell seals endure brady-arrythmias during their dives when desaturating to 3.2 kPa and elite breath-hold-divers (BHD), who share metabolic and cardiovascular adaptions including bradycardia with diving mammals, endure similar desaturation during maximum apnea. We hypothesized that hypoxia causes brady-arrythmias during maximum apnea in elite BHD. Hence, this study aimed to define the arterial blood glucose (Glu), peripheral saturation (SAT), heart rhythm (HR), and mean arterial blood pressure (MAP) of elite BHD during maximum apneas.Methods: HR was monitored with Direct-Current-Pads/ECG-lead-II and MAP and Glu from a radial arterial-catheter in nine BHD performing an immersed and head-down maximal static pool apnea after three warm-up apneas. SAT was monitored with a sensor on the neck of the subjects. On a separate day, a 12-lead-ECG-monitored maximum static apnea was repeated dry (n = 6).Results: During pool apnea of maximum duration (385 ± 70 s), SAT decreased from 99.6 ± 0.5 to 58.5 ± 5.5% (∼PaO2 4.8 ± 1.5 kPa, P < 0.001), while Glu increased from 5.8 ± 0.2 to 6.2 ± 0.2 mmol/l (P = 0.009). MAP increased from 103 ± 4 to 155 ± 6 mm Hg (P < 0.005). HR decreased to 46 ± 10 from 86 ± 14 beats/minute (P < 0.001). HR and MAP were unchanged after 3–4 min of apnea. During dry apnea (378 ± 31 s), HR decreased from 55 ± 4 to 40 ± 3 beats/minute (P = 0.031). Atrioventricular dissociation and junctional rhythm were observed both during pool and dry apneas.Conclusion: Our findings contrast with previous studies concluding that Glu decreases during apnea diving. We conclude during maximum apnea in elite BHD that (1) the diving reflex is maximized after 3–4 min, (2) increasing Glu may indicate lactate metabolism in accordance with our previous results, and (3) extreme hypoxia rather than hypoglycemia causes brady-arrythmias in elite BHD similar to diving mammals. |
format |
Article in Journal/Newspaper |
author |
Thomas Kjeld Anders Brenøe Isbrand Katrine Linnet Bo Zerahn Jens Højberg Egon Godthaab Hansen Lars Christian Gormsen Jacob Bejder Thomas Krag John Vissing Hans Erik Bøtker Henrik Christian Arendrup |
author_facet |
Thomas Kjeld Anders Brenøe Isbrand Katrine Linnet Bo Zerahn Jens Højberg Egon Godthaab Hansen Lars Christian Gormsen Jacob Bejder Thomas Krag John Vissing Hans Erik Bøtker Henrik Christian Arendrup |
author_sort |
Thomas Kjeld |
title |
Extreme Hypoxia Causing Brady-Arrythmias During Apnea in Elite Breath-Hold Divers |
title_short |
Extreme Hypoxia Causing Brady-Arrythmias During Apnea in Elite Breath-Hold Divers |
title_full |
Extreme Hypoxia Causing Brady-Arrythmias During Apnea in Elite Breath-Hold Divers |
title_fullStr |
Extreme Hypoxia Causing Brady-Arrythmias During Apnea in Elite Breath-Hold Divers |
title_full_unstemmed |
Extreme Hypoxia Causing Brady-Arrythmias During Apnea in Elite Breath-Hold Divers |
title_sort |
extreme hypoxia causing brady-arrythmias during apnea in elite breath-hold divers |
publisher |
Frontiers Media S.A. |
publishDate |
2021 |
url |
https://doi.org/10.3389/fphys.2021.712573 https://doaj.org/article/9bf5e0c58cbf41e9a56c5e2c60e08606 |
geographic |
Weddell |
geographic_facet |
Weddell |
genre |
Weddell Seals |
genre_facet |
Weddell Seals |
op_source |
Frontiers in Physiology, Vol 12 (2021) |
op_relation |
https://www.frontiersin.org/articles/10.3389/fphys.2021.712573/full https://doaj.org/toc/1664-042X 1664-042X doi:10.3389/fphys.2021.712573 https://doaj.org/article/9bf5e0c58cbf41e9a56c5e2c60e08606 |
op_doi |
https://doi.org/10.3389/fphys.2021.712573 |
container_title |
Frontiers in Physiology |
container_volume |
12 |
_version_ |
1766233801862676480 |