Variability in circulating gas emboli after a same scuba diving exposure
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A reduction in ambient pressure or decompression from scuba diving can result in ultrasound-detectable venous gas emboli (VGE). These environmental exposures carry a risk of decompression sickness (DCS) which is mitigated by adherence to decompression schedules; however, bubbles are routinely observed for dives well within these limits and significant inter-personal variability in DCS risk exists. Here, we assess the variability and evolution of VGE for 2 h post-dive using echocardiography, following a standardized pool dive in calm warm conditions.
14 divers performed either one or two (with a 24 h interval) standardized scuba dives to 33 mfw (400 kPa) for 20 min of immersion time at NEMO 33 in Brussels, Belgium. Measurements were performed at 21, 56, 91 and 126 min post-dive: bubbles were counted for all 68 echocardiography recordings and the average over ten consecutive cardiac cycles taken as the bubble score.
Significant inter-personal variability was demonstrated despite all divers following the same protocol in controlled pool conditions: in the detection or not of VGE, in the peak VGE score, as well as time to VGE peak. In addition, intra-personal differences in 2/3 of the consecutive day dives were seen (lower VGE counts or faster clearance).
Since VGE evolution post-dive varies between people, more work is clearly needed to isolate contributing factors. In this respect, going toward a more continuous evaluation, or developing new means to detect decompression stress markers, may offer the ability to better assess dynamic correlations to other physiological parameters.
KeywordsEchocardiography Venous gas emboli Ultrasound Decompression sickness Microbubble
Venous gas emboli
The authors wish to thank the NEMO33 pool for kindly hosting us after hours, all the volunteers who so generously donated their time, as well as Mindray for technical support. This work was supported in part by the PHYPODE project, funded by the European Union under a Marie Curie Initial Training Network (FP7-PEOPLE-2010-ITN program, Grant Agreement No. 264816), as well as the Divers Alert Network/R.W. (Bill) Hamilton Memorial Dive Medicine Research Grant (VP award 2017) administered by the Women Divers Hall of Fame.
VP, PG, DC, MXT and CB substantially contributed to conception and design of the study. VP, GO and AB acquired all the data. ST supervised and coordinated all diving and measurement schedule adherence. VP, PG, DC, RJE, PAD, GO, AB, MXT, ST and CB substantially contributed to data analysis and interpretation. VP drafted the article. PG, DC, RJE, PAD, GO, AB, MXT, ST and CB revised the article critically for important intellectual content. Additional information: sadly, coauthor David Cosgrove (DC) passed away. All other authors read and approved the final version of the manuscript.
- Balestra C, Marroni A, Farkas B, Peetrons P, Vanderschueren F, Duboc E, Snoeck T, Germonpré P (2004) The fractal approach as a tool to understand asymptomatic brain hyperintense MRI signals. Fractal Complex Geometry Patterns Scaling Nat Soc 12(1):67–72. https://doi.org/10.1142/S0218348x0400232x CrossRefGoogle Scholar
- Balestra C, Theunissen S, Papadopoulou V, Le Mener C, Germonpré P, Guerrero F, Lafère P (2016) Pre-dive whole-body vibration better reduces decompression-induced vascular gas emboli than oxygenation or a combination of both. Front Physiol. https://doi.org/10.3389/fphys.2016.00586 PubMedPubMedCentralCrossRefGoogle Scholar
- Blogg SL, Gennser M (2011) The need for optimisation of post-dive ultrasound monitoring to properly evaluate the evolution of venous gas emboli. Diving Hyperbaric Med 41(3):139–146Google Scholar
- Eatock BC, Nishi RY (1986) Procedures for doppler ultrasonic monitoring of divers for intravascular bubbles. DCIEM No. 86-C-25. Defence and Civil Institute of Environmental Medicine, Ontario, CanadaGoogle Scholar
- Germonpré P, Papadopoulou V, Hemelryck W, Obeid G, Lafère P, Eckersley RJ, Tang MX, Balestra C (2014) The use of portable 2D echocardiography and ‘frame-based’ bubble counting as a tool to evaluate diving decompression stress. Diving Hyperbaric Med 44(1):5–13Google Scholar
- Hensel JSE, Le DQ, Balestra C, Tang MX, Dayton PA, Papadopoulou V (2018) Nonlinear microbubble ultrasound imaging for improved decompression stress quantification in humans. In: The 23rd European symposium on ultrasound contrast imaging, Rotterdam, The NetherlandsGoogle Scholar
- Lambrechts K, Pontier JM, Balestra C, Mazur A, Wang Q, Buzzacott P, Theron M, Mansourati J, Guerrero F (2013) Effect of a single, open-sea, air scuba dive on human micro- and macrovascular function. Eur J Appl Physiol 113(10):2637–2645. https://doi.org/10.1007/s00421-013-2676-x CrossRefPubMedGoogle Scholar
- Lambrechts K, Balestra C, Theron M, Henckes A, Galinat H, Mignant F, Belhomme M, Pontier JM, Guerrero F (2017) Venous gas emboli are involved in post-dive macro, but not microvascular dysfunction. Eur J Appl Physiol 117(2):335–344. https://doi.org/10.1007/s00421-017-3537-9 CrossRefPubMedGoogle Scholar
- Mollerlokken A, Blogg SL, Doolette DJ, Nishi RY, Pollock NW (2016) Consensus guidelines for the use of ultrasound for diving research. Diving Hyperbaric Med 46(1):26–32Google Scholar
- NAVSEA (2016) Air decompression. In: US Navy diving manual (revision 7). Government Printing Office, Washington, DC, pp 9–75Google Scholar
- Nishi RY, Brubakk AO, Eftedal OS (2003) Bubble detection. In: Brubakk AO, Neuman TS (eds) Bennett and Elliott’s physiology and medicine of diving, 5th edn. WB Saunders, Philadelphia, PA, pp 501–529Google Scholar
- Papadopoulou V, Hui JH, Balestra C, Hemelryck W, Germonpré P, Eckersley RJ, Tang MX (2013b) Automated counting of venous gas emboli in post-SCUBA dive echocardiography. In: IEEE-UFFC conference, Prague, Czech RepublicGoogle Scholar
- Papadopoulou V, Hui JH, Balestra C, Hemelryck W, Germonpré P, Eckersley RJ, Tang MX (2013c) Evaluating the counting of venous gas emboli on post-scuba dive echocardiographs. In: Proceedings of the tri-continental scientific meeting on diving and hyperbaric medicine, Reunion Island, FranceGoogle Scholar
- Papadopoulou V, Balestra C, Theunissen S, Germonpré P, Obeid G, Boutros A, Eckersley RJ, Dayton PA, Cosgrove D, Tang M-X (2017) Can current contrast mode echocardiography help estimate bubble population dynamics post-dive? In: The European Underwater and Baromedical Society (EUBS) conference proceedings, Ravenna, ItalyGoogle Scholar
- Parlak IB, Egi SM, Ademoglu A, Balestra C, Germonpré P, Marroni A (2011) Intelligent bubble recognition on cardiac videos using Gabor wavelet. Int J Digital Inf Wirel Commun 1:195–203Google Scholar
- Sawatzky KD (1991) The relationship between intravascular Doppler-detected gas bubbles and decompression sickness after bounce diving in humans. York University, Toronto, ONGoogle Scholar
- Swan JG, Bollinger BD, Donoghue TG, Wilbur JC, Phillips SD, Alvarenga DL, Knaus DA, Magari PJ, Buckey JC (2011) Microbubble detection following hyperbaric chamber dives using dual-frequency ultrasound. J Appl Physiol (1985) 111(5):1323–1328. https://doi.org/10.1152/japplphysiol.01203.2010 CrossRefGoogle Scholar