Publications
Une sélection de publications scientifiques portant sur la médecine et la physiologie de la plongée.
2012 déc. 12
Persistence of critical flicker fusion frequency impairment after a 33 mfw SCUBA dive: evidence of prolonged nitrogen narcosis?
Balestra C, Lafère P, Germonpré P.

One of the possible risks incurred while diving is inert gas narcosis (IGN), yet its mechanism of action remains a matter of controversy. Although providing insights in the basic mechanisms of IGN, research has been primarily limited to animal studies. A human study, in real diving conditions, was needed. Twenty volunteers within strict biometrical criteria (male, age 30-40 years, BMI 20-23, non smoker) were selected. They performed a no-decompression dive to a depth of 33 mfw for 20 min and were assessed by the means of critical flicker fusion frequency (CFFF) measurement before the dive, during the dive upon arriving at the bottom, 5 min before the ascent, and 30 min after surfacing. After this late measurement, divers breathed oxygen for 15 min and were assessed a final time. Compared to the pre-dive value the mean value of each measurement was significantly different (p < 0.001). An increase of CFFF to 104 ± 5.1 % upon arriving to the bottom is followed by a decrease to 93.5 ± 4.3 %. This impairment of CFFF persisted 30 min after surfacing, still decreased to 96.3 ± 8.2 % compared to pre-dive CFFF. Post-dive measures made after 15 min of oxygen were not different from control (without nitrogen supersaturation), 124.4 ± 10.8 versus 124.2 ± 3.9 %. This simple study suggests that IGN (at least partially) depends on gas-protein interactions and that the cerebral impairment persists for at least 30 min after surfacing. This could be an important consideration in situations where precise and accurate judgment or actions are essential.

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2021 sept. 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.

Physiological and Clinical Impact of Repeated Inhaled Oxygen Variation on Erythropoietin Levels in Patients After Surgery. Oxygen exposure duration and inspired oxygen fraction required to observe a significant increase in EPO or hemoglobin are not clearly defined.

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2020 juil. 23
Physiological characteristics associated with increased resistance to decompression sickness in male and female rats
Lautridou J, Dugrenot E, Amerand A, Guernec A, Pichavant-Rafini K, Goanvec C, Inizan M, Albacete G, Belhomme M, Galinat H, Lafere P, Balestra C, Moisan C, Buzzacott P & Guerrero F.

Decompression sickness (DCS) is a complex and poorly understood systemic disease with wide interindividual resistance variability. We selectively bred rats with a threefold greater resistance to DCS than standard ones. To investigate possible physiological mechanisms underlying the resistance to DCS, including sex-related differences in these mechanisms, 15 males and 15 females resistant to DCS were compared with aged-matched standard Wistar males (n = 15) and females (n = 15). None of these individuals had been previously exposed to hyperbaric treatment. Comparison of the allelic frequencies of single nucleotide polymorphisms (SNPs) showed a difference of one SNP located on the X chromosome.

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2021 août 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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2021 nov. 28
Physiology of repeated mixed gas 100-m wreck dives using a closed-circuit rebreather: a field bubble study
Balestra C, Guerrero F, Theunissen S, Germonpre P & Lafere P.

Purpose Data regarding decompression stress after deep closed-circuit rebreather (CCR) dives are scarce. This study aimed to monitor technical divers during a wreck diving expedition and provide an insight in venous gas emboli (VGE) dynamics. Methods Diving practices of ten technical divers were observed. They performed a series of three consecutive daily dives around 100 m.

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