Selected scientific publications on diving medicine and physiology.

2007 Nov 30
Effect of varying deep stop times and shallow stop times on precordial bubbles after dives to 25 msw (82 fsw)
Bennett PB1, Marroni A, Cronje FJ, Cali-Corleo R, Germonpre P, Pieri M, Bonuccelli C, Leonardi MG, Balestra C.

In our previous research, a deep 5-min stop at 15 msw (50 fsw), in addition to the typical 3-5 min shallow stop, significantly reduced precordial Doppler detectable bubbles (PDDB) and "fast" tissue compartment gas tensions during decompression from a 25 msw (82 fsw) dive; the optimal ascent rate was 10 msw (30 fsw/min). Since publication of these results, several recreational diving agencies have recommended empirical stop times shorter than the 5 min stops that we used, stops of as little as 1 min (deep) and 2 min (shallow). In our present study, we clarified the optimal time for stops by measuring PDDB with several combinations of deep and shallow stop times following single and repetitive open-water dives to 25 msw (82 fsw) for 25 mins and 20 minutes respectively; ascent rate was 10 msw/min (33 fsw). Among 15 profiles, stop time ranged from 1 to 10 min for both the deep stops (15 msw/50 fsw) and the shallow stops (6 msw/20 fsw). Dives with 2 1/2 min deep stops yielded the lowest PDDB scores--shorter or longer deep stops were less effective in reducing PDDB. The results confirm that a deep stop of 1 min is too short--it produced the highest PDDB scores of all the dives. We also evaluated shallow stop times of 5, 4, 3, 2 and 1 min while keeping a fixed time of 2.5 min for the deep stop; increased times up to 10 min at the shallow stop did not further reduce PDDB. While our findings cannot be extrapolated beyond these dive profiles without further study, we recommend a deep stop of at least 2 1/2 mins at 15 msw (50 fsw) in addition to the customary 6 msw (20 fsw) for 3-5 mins for 25 meter dives of 20 to 25 minutes to reduce PDDB.

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2009 Apr 5
Safety of recreational scuba diving in type 1 diabetic patients: the Deep Monitoring programme
Bonomo M1, Cairoli R, Verde G, Morelli L, Moreo A, Grottaglie MD, Brambilla MC, Meneghini E, Aghemo P, Corigliano G, Marroni A.

To verify whether, with thorough practical and theoretical training, well-controlled, non-complicated diabetic patients can safely go diving underwater with no additional medical or metabolic risks. METHODS: Twelve diabetic patients participated in the study after undergoing training focused on their diabetic status. Two dives per day were scheduled during two five-day stays on the island of Ventotene (Italy). Capillary blood glucose (BG) was checked at 60, 30 and 10 minutes before diving, and corrective measures adopted if necessary, based on BG absolute levels and dynamics. A device for continuous subcutaneous glucose monitoring (CGM), expressly modified for the purpose, was worn during dives.

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2009 Mar 3
Preventive effect of pre-dive hydration on bubble formation in divers
Gempp E, Blatteau JE, Pontier JM, Balestra C, Louge P.

OBJECTIVE: To investigate whether prehydration 90 min before a dive could decrease bubble formation, and to evaluate the consequent adjustments in plasma volume (PV), water balance and plasma surface tension (ST).

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2010 Jan 2
Pre-dive vibration effect on bubble formation after a 30-m dive requiring a decompression stop
Germonpré P1, Pontier JM, Gempp E, Blatteau JE, Deneweth S, Lafère P, Marroni A, Balestra C.

INTRODUCTION: The preconditioning of divers to reduce post-dive decompression sickness (DCS) has gained increased interest in diving medical research over the last few years. The beneficial effects of physical exercise, oxygen breathing, hyperbaric exposure, heat exposure, hyperhydration, or nitroglycerin administration before the dive are only a few examples of ongoing research. In this work, we investigated the effects of pre-dive whole-body vibration on post-dive bubble formation.

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2010 Sep 10
Evaluation of critical flicker fusion frequency and perceived fatigue in divers after air and enriched air nitrox diving
Lafère P, Balestra C, Hemelryck W, Donda N, Sakr A, Taher A, Marroni S, Germonpré P.

INTRODUCTION: Many divers report less fatigue following dives breathing enriched air nitrox (EANx) compared with breathing air. A reduction of post-dive fatigue with EANx would suggest a pathological origin, possibly the presence of asymptomatic nitrogen bubbles in the body after a dive.

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