Selected scientific publications on diving medicine and physiology.

2016 Feb 14
Serum erythropoietin levels in healthy humans after a short period of normobaric and hyperbaric oxygen breathing: the "normobaric oxygen paradox"
Balestra C, Germonpré P, Poortmans JR, Marroni A.

Renal (peritubular) tissue hypoxia is a well-known physiological trigger for erythropoietin (EPO) production. We investigated the effect of rebound relative hypoxia after hyperoxia obtained under normo- and hyperbaric oxygen breathing conditions. A group of 16 healthy volunteers were investigated before and after a period of breathing 100% normobaric oxygen for 2 h and a period of breathing 100% oxygen at 2.5 ATA for 90 min (hyperbaric oxygen). Serum EPO concentration was measured using a radioimmunoassay at various time points during 24-36 h. A 60% increase (P < 0.001) in serum EPO was observed 36 h after normobaric oxygen. In contrast, a 53% decrease in serum EPO was observed at 24 h after hyperbaric oxygen. Those changes were not related to the circadian rhythm of serum EPO of the subjects. These results indicate that a sudden and sustained decrease in tissue oxygen tension, even above hypoxia thresholds (e.g., after a period of normobaric oxygen breathing), may act as a trigger for EPO serum level. This EPO trigger, the "normobaric oxygen paradox," does not appear to be present after hyperbaric oxygen breathing.

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2016 Jan 1
CADDY Project, Year 2: The First Validation Trials
Mišković N., Pascoal A., Bibuli M., Caccia M., Neasham J. A., Birk A., Egi M., Grammer K., Marroni A., Vasilijević A., Vukić Z.

"CADDY - Cognitive Autonomous Diving Buddy" is an FP7 project that that is devoted to developing a cognitive underwater robotic system that will help divers during their activities in this hazardous environment. The envisioned resulting system will play a threefold role similar to those that a human buddy diver should have: buddy "observer", buddy "slave", and buddy "guide". During the second year of the project, validation trials were organized in Croatia with the purpose of testing all developed algorithms that will enable the three roles of the CADDY system. The trials were structured in five experiments. This paper is devoted to providing a concise overview of the conducted experiments and major results.

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2015 Dec 1
Cutis Marmorata skin decompression sickness is a manifestation of brainstem bubble embolization, not of local skin bubbles.
Germonpre P, Balestra C, Obeid G, Caers D.

"Cutis Marmorata" skin symptoms after diving, most frequently in the form of an itching or painful cutaneous red-bluish discoloration are commonly regarded as a mild form of decompression sickness (DCS), and treated with oxygen inhalation without reverting to hyperbaric recompression treatment...

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2015 Sep 1
Association of microparticles and neutrophil activation with decompression sickness.
Thom SR, Bennett M, Banham ND, Chin W, Blake DF, Rosen A, Pollock NW, Madden D, Barak O, Marroni A, Balestra C, Germonpre P, Pieri M, Cialoni D, Le PN, Logue C, Lambert D, Hardy KR, Sward D, Yang M, Bhopale VB, Dujic Z.

Decompression sickness (DCS) is a systemic disorder, assumed due to gas bubbles, but additional factors are likely to play a role. Circulating microparticles (MPs)--vesicular structures with diameters of 0.1-1.0 μm--have been implicated, but data in human divers have been lacking...

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2015 Jul 1
Heart rate variability and critical flicker fusion frequency changes during and after parachute jumping in experienced skydivers.
Cavalade, Papadopoulou V, Theunissen S, Balestra C.

PURPOSE: The purpose of this study was (1) to further explore the heart rate dynamics and assess a potential cardiovascular risk in response to 4000 m jumps in experienced skydivers; (2) to assess whether there is an impact of such jumps on skydivers' cortical arousal or not, which may impact their decision making processes...

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