Increased ventilatory response to carbon dioxide after dive training
Ekman, Lars LU ; Sjöblom, Clara LU ; Ekström, Magnus LU
and Frånberg, Oskar
LU
(2025)
In Undersea & hyperbaric medicine : journal of the Undersea and Hyperbaric Medical Society, Inc
52(4).
p.587-597
- Abstract
Introduction: Divers are reported to have a lower ventilatory response to elevated levels of carbon dioxide (CO₂) than non-divers. Hypoventilation with CO₂ retention during diving is potentially dangerous. It is unknown if CO₂ retention is largely inherited or develops during diving training. We aimed to investigate if a military dive training course would influence the ventilatory response to CO₂. Methods: Novice rebreather Divers with Amphibious Rangers as controls were tested at baseline, after 12 weeks of water exercise training, and after 15 weeks of diving: participants rebreathed in a Douglas bag filled with an initial 100% oxygen, resulting in increasing levels of inspiratory CO₂ (iCO₂). The test was performed until... (More)
Introduction: Divers are reported to have a lower ventilatory response to elevated levels of carbon dioxide (CO₂) than non-divers. Hypoventilation with CO₂ retention during diving is potentially dangerous. It is unknown if CO₂ retention is largely inherited or develops during diving training. We aimed to investigate if a military dive training course would influence the ventilatory response to CO₂. Methods: Novice rebreather Divers with Amphibious Rangers as controls were tested at baseline, after 12 weeks of water exercise training, and after 15 weeks of diving: participants rebreathed in a Douglas bag filled with an initial 100% oxygen, resulting in increasing levels of inspiratory CO₂ (iCO₂). The test was performed until symptom-limitation or an expiratory CO₂ of 8.0 kPa. To decrease conscious control of breathing, participants were distracted with a memory game during the test. Differences between groups and over time were analyzed using independent and paired t-tests. Results: Ten Divers and six Amphibious Rangers completed baseline testing and eight Divers completed all tests. Divers had a statistically significant higher Minute Ventilation (V'E) after dive training, compared to after water exercise training and baseline, at all levels of iCO₂. However, the change in Hypercapnic ventilatory response (HCVR) before and after dive training across pCO₂ values 5.0-7.9, did not reach statistical significance. At baseline, Amphibious Rangers had a non-significant higher V'E compared to Divers at higher levels of iCO₂. Conclusion: A military rebreather diving program might be associated with increased ventilatory response to CO₂.
(Less)
- author
- Ekman, Lars
LU
; Sjöblom, Clara
LU
; Ekström, Magnus
LU
and Frånberg, Oskar
LU
- organization
- publishing date
- 2025-10-01
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- carbon dioxide retention, diving, rebreather-semi-closed circuit respiratory response
- in
- Undersea & hyperbaric medicine : journal of the Undersea and Hyperbaric Medical Society, Inc
- volume
- 52
- issue
- 4
- pages
- 11 pages
- publisher
- Undersea and Hyperbaric Medical Society
- external identifiers
-
- pmid:41429036
- scopus:105025600566
- ISSN
- 1066-2936
- language
- English
- LU publication?
- yes
- additional info
- Publisher Copyright: Copyright© Undersea and Hyperbaric Medical Society.
- id
- 0226eff1-b37f-4872-8c6d-b3c180be3d96
- date added to LUP
- 2026-02-23 14:18:23
- date last changed
- 2026-06-16 05:36:50
@article{0226eff1-b37f-4872-8c6d-b3c180be3d96,
abstract = {{<p>Introduction: Divers are reported to have a lower ventilatory response to elevated levels of carbon dioxide (CO₂) than non-divers. Hypoventilation with CO₂ retention during diving is potentially dangerous. It is unknown if CO₂ retention is largely inherited or develops during diving training. We aimed to investigate if a military dive training course would influence the ventilatory response to CO₂. Methods: Novice rebreather Divers with Amphibious Rangers as controls were tested at baseline, after 12 weeks of water exercise training, and after 15 weeks of diving: participants rebreathed in a Douglas bag filled with an initial 100% oxygen, resulting in increasing levels of inspiratory CO₂ (iCO₂). The test was performed until symptom-limitation or an expiratory CO₂ of 8.0 kPa. To decrease conscious control of breathing, participants were distracted with a memory game during the test. Differences between groups and over time were analyzed using independent and paired t-tests. Results: Ten Divers and six Amphibious Rangers completed baseline testing and eight Divers completed all tests. Divers had a statistically significant higher Minute Ventilation (V'E) after dive training, compared to after water exercise training and baseline, at all levels of iCO₂. However, the change in Hypercapnic ventilatory response (HCVR) before and after dive training across pCO₂ values 5.0-7.9, did not reach statistical significance. At baseline, Amphibious Rangers had a non-significant higher V'E compared to Divers at higher levels of iCO₂. Conclusion: A military rebreather diving program might be associated with increased ventilatory response to CO₂.</p>}},
author = {{Ekman, Lars and Sjöblom, Clara and Ekström, Magnus and Frånberg, Oskar}},
issn = {{1066-2936}},
keywords = {{carbon dioxide retention; diving; rebreather-semi-closed circuit respiratory response}},
language = {{eng}},
month = {{10}},
number = {{4}},
pages = {{587--597}},
publisher = {{Undersea and Hyperbaric Medical Society}},
series = {{Undersea & hyperbaric medicine : journal of the Undersea and Hyperbaric Medical Society, Inc}},
title = {{Increased ventilatory response to carbon dioxide after dive training}},
volume = {{52}},
year = {{2025}},
}