Selected scientific publications on diving medicine and physiology.

2021 Sep 29
Comparison of insulation provided by dry or wetsuits among recreational divers during cold water immersion ( < 5°C)
Pierre Lafère, François Guerrero, Peter Germonpré, Costantino Balestra

Background: Divers thermal status influences susceptibility to decompression sickness hence the need for proper insulation during immersion in cold water. However, there is a lack of data on thermal protection provided by diving suits, hence this study.

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2021 Sep 27
Physiological and Clinical Impact of Repeated Inhaled Oxygen Variation on Erythropoietin Levels in Patients After Surgery
Khalife M, Ben Aziz M, Balestra C, Valsamis J & Sosnowski M.

The “Normobaric Oxygen Paradox” (NOP) is a physiologic mechanism that induces an increase of endogenous erythropoietin (EPO) production by creating a state of relative hypoxia in subjects previously exposed to hyperoxia, followed by a rapid return to normoxia.

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2021 Sep 16
Oxidative Stress and Inflammation, MicroRNA, and Hemoglobin Variations after Administration of Oxygen at Different Pressures and Concentrations: A Randomized Trial
Bosco G, Paganini M, Giacon TA, Oppio A, Vezzoli A, Dellanoce C, Moro T, Paoli A, Zanotti F, Zavan B, Balestra C & Mrakic-Sposta S.

Exercise generates reactive oxygen species (ROS), creating a redox imbalance towards oxidation when inadequately intense. Normobaric and hyperbaric oxygen (HBO) breathed while not exercising induces antioxidant enzymes expression, but literature is still poor.

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2021 Sep 4
Hypoxic and Hyperoxic Breathing as a Complement to Low-Intensity Physical Exercise Programs: A Proof-of-Principle Study
Balestra C, Lambrechts K, Mrakic-Sposta S, Vezzoli A, Levenez M, Germonpre P, Virgili F, Bosco G, Lafere P

Inflammation is an adaptive response to both external and internal stimuli including infection, trauma, surgery, ischemia-reperfusion, or malignancy. A number of studies indicate that physical activity is an effective means of reducing acute systemic and low-level inflammation occurring in different pathological conditions and in the recovery phase after disease. As a proof-of-principle, we hypothesized that low-intensity workout performed under modified oxygen supply would elicit a “metabolic exercise” inducing a hormetic response, increasing the metabolic load and oxidative stress with the same overall effect expected after a higher intensity or charge exercise.

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2021 Aug 25
Physiological effects of mixed-gas deep sea dives using a closed-circuit rebreather: a field pilot study
Dugrenot E, Balestra C, Gouin E, L'Her E & Guerrero F.

Purpose: Deep diving using mixed gas with closed-circuit rebreathers (CCRs) is increasingly common. However, data regarding the effects of these dives are still scarce. This preliminary field study aimed at evaluating the acute effects of deep (90-120 msw) mixed-gas CCR bounce dives on lung function in relation with other physiological parameters. Methods: Seven divers performed a total of sixteen open-sea CCR dives breathing gas mixture of helium, nitrogen and oxygen (trimix) within four days at 2 depths (90 and 120 msw). Spirometric parameters, SpO2, body mass, hematocrit, short term heart rate variability (HRV) and critical flicker fusion frequency (CFFF) were measured at rest 60 min before the dive and 120 min after surfacing.

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