Elevations in Intra-cranial blood flow velocities following a SCUBA Dive and the Influence of Post-dive Exercise

Abstract

The effect that a SCUBA dive has on cerebral blood flow (CBF) at rest and during exercise is poorly understood. We examined the hypothesis that the altered hemodynamic parameters following a SCUBA dive will lead to differential changes in CBF at rest and during exercise. 16 divers completed a field-based study with a single dive at a depth of 18 m sea water with a 47-min bottom time. A follow-up laboratory based study was conducted – 1 week later. Intra-cranial velocities were measured with transcranial Doppler ultrasound (TCD) pre-dive, post-dive at rest and throughout incremental exercise until exhaustion. Following the dive at rest, middle cerebral artery velocity (MCAv) was elevated 15 and 30 min after surfacing (by 3.3±5.8 and 4.0±6.9 cm/s, respectively; p<0.05); posterior cerebral artery velocity (PCAv) was increased at 30 min after surfacing (by 3.0±4.5 cm/s; p<0.05). During exercise following the dive, both MCAv and PCAv increased up to 150W followed by a decrease towards baseline at 180W (p<0.05). We found no difference in CBV during exercise between field and laboratory studies (p<0.05). The novel finding of this study is the transient elevation in resting intra-cranial velocities within 30 min following a SCUBA dive.

Key words

SCUBA diving - cerebral blood flow - transcranial doppler ultrasound

^* Authors contributed equally

• References

• 1 Ainslie PN, Shaw AD, Smith KJ, Willie CK, Ikeda K, Graham J, Macleod DB. Stability of cerebral metabolism and substrate availability in humans during hypoxia and hyperoxia. Clin Sci 2014; 126: 661-670
• 2 Ainslie PN, Smith KJ. Integrated human physiology: breathing, blood pressure and blood flow to the brain. J Physiol 2011; 589: 2917-2917
• 3 Barak OF, Madden D, Lovering AT, Lambrechts K, Ljubkovic M, Dujić Z. Very Few Exercise-Induced Arterialized Gas Bubbles Reach the Cerebral Vasculature. Med Sci Sport Exer 2015; 47: 1798-1805
• 4 Bilopavlovic N, Marinovic J, Ljubkovic M, Obad A, Zanchi J, Pollock NW, Denoble P, Dujić Z. Effect of repetitive SCUBA diving on humoral markers of endothelial and central nervous system integrity. Eur J Appl Physiol 2013; 113: 1737-1743
• 5 Blatteau JE, Boussuges A, Gempp E, Pontier JM, Castagna O, Robinet C, Galland FM, Bourdon L. Haemodynamic changes induced by submaximal exercise before a dive and its consequences on bubble formation. Brit J Sports Med 2007; 41: 375-379
• 6 Boussuges A, Retali G, Bodéré-Melin M, Gardette B, Carturan D. Gender differences in circulating bubble production after SCUBA diving. Clin Physiol Funct I 2009; 29: 400-405
• 7 Brodsky SV, Zhang F, Nasjletti A, Goligorsky MS. Endothelium-derived microparticles impair endothelial function in vitro. Am J Physiol 2004; 286: H1910-H1915
• 8 Brubakk AO, Duplancić D, Valic Z, Palada I, Obad A, Bakovic D, Wisløff U, Dujić Z. A single air dive reduces arterial endothelial function in man. J Physiol 2005; 566: 901-906
• 9 Demchenko IT, Boso AE, O'Neill TJ, Bennett PB, Piantadosi CA. Nitric oxide and cerebral blood flow responses to hyperbaric oxygen. J Appl Physiol 2000; 88: 1381-1389
• 10 Dujić Z, Bakovic D, Marinovic-Terzic I, Eterović D. Acute effects of a single open sea air dive and post-dive posture on cardiac output and pulmonary gas exchange in recreational divers. Brit J Sport Med 2005; 39: 1-7
• 11 Dujić Z, Eterović D, Denoble P, Krstacić G, Tocilj J, Gosović S. Effect of a single air dive on pulmonary diffusing capacity in professional divers. J Appl Physiol 1993; 74: 55-61
• 12 Dujić Z, Obad A, Palada I, Valic Z, Brubakk AO. A single open sea air dive increases pulmonary artery pressure and reduces right ventricular function in professional divers. Eur J Appl Physiol 2006; 97: 478-485
• 13 Eftedal O, Brubakk AO. Agreement between trained and untrained observers in grading intravascular bubble signals in ultrasonic images. Undersea Hyperbar Med 1997; 24: 293-299
• 14 Eldridge MW. Exercise-induced intrapulmonary arteriovenous shunting in healthy humans. J Appl Physiol 2004; 97: 797-805
• 15 Florian JP, Simmons EE, Chon KH, Faes L, Shykoff BE. Cardiovascular and autonomic responses to physiological stressors before and after six hours of water immersion. J Appl Physiol 2013; 115: 1275-1289
• 16 Floyd TF, Clark JM, Gelfand R, Detre JA, Ratcliffe S, Guvakov D, Lambertsen CJ, Eckenhoff RG. Independent cerebral vasoconstrictive effects of hyperoxia and accompanying arterial hypocapnia at 1 ATA. J Appl Physiol 2003; 95: 2453-2461
• 17 Harriss DJ, Atkinson G. Ethical standards in sport and exercise science research: 2016 update. Int J Sports Med 2016; 36: 1121-1124
• 18 Kety SS, Schmidt CF. The effects of altered arterial tensions of carbon dioxide and oxygen on cerebral blood flow and cerebral oxygen consumption of normal young men. J Clin Invest 1948; 27: 484-492
• 19 Klien S, Spiegel M, Engelhardt K, Schmidauer C, Ulmer H, Diepers M, Schmutzhard E, Mutzbauer T. Menstrual cycle dependent right-to-left shunting: a single-blinded transcranial Doppler sonography study. Undersea Hyperbar Med 2005; 32: 403-407
• 20 Lambertsen CJ, Dough RH, Cooper DY, Emmel GL, Loeschcke HH, Schmidt CF. Oxygen toxicity; effects in man of oxygen inhalation at 1 and 3.5 atmospheres upon blood gas transport, cerebral circulation and cerebral metabolism. J Appl Physiol 1953; 5: 471-486
• 21 Lambrechts K, Pontier J-M, Balestra C, Mazur A, Wang Q, Buzzacott P, Theron M, Mansourati J, Guerrero F. Effect of a single, open-sea, air scuba dive on human micro- and macrovascular function. Eur J Appl Physiol 2013; 113: 2637-2645
• 22 Ljubkovic M, Dujić Z, Møllerløkken A, Bakovic D, Obad A, Breskovic T, Brubakk AO. Venous and arterial bubbles at rest after no-decompression air dives. Med Sci Sport Exer 2011; 43: 990-995
• 23 Ljubkovic M, Zanchi J, Breskovic T, Marinovic J, Lojpur M, Dujić Z. Determinants of arterial gas embolism after scuba diving. J Appl Physiol 2012; 112: 91-95
• 24 Lovering AT, Romer LM, Haverkamp HC, Pegelow DF, Hokanson JS, Eldridge MW. Intrapulmonary shunting and pulmonary gas exchange during normoxic and hypoxic exercise in healthy humans. J Appl Physiol 2008; 104: 1418-1425
• 25 Lozo M, Madden D, Gunjaca G, Ljubkovic M, Marinovic J, Dujić Z. The impact of consecutive freshwater trimix dives at altitude on human cardiovascular function. Clin Physiol Funct I 2015; 35: 142-149
• 26 Madden D, Barak OF, Thom SR, Yang M, Bhopale VM, Ljubkovic M, Dujić Z. The impact of predive exercise on repetitive SCUBA diving. Clin Physiol Funct I 2014;
• 27 Madden D, Ljubkovic M, Dujić Z. Intrapulmonary Shunt and SCUBA Diving: Another Risk Factor?. Echocardiography 2015; 32: S205-S210
• 28 Madden D, Lozo M, Dujić Z, Ljubkovic M. Exercise after SCUBA diving increases the incidence of arterial gas embolism. J Appl Physiol 2013; 115: 716-722
• 29 Madden D, Thom SR, Milovanova TN, Yang M, Bhopale VM, Ljubkovic M, Dujić Z. Exercise before scuba diving ameliorates decompression-induced neutrophil activation. Med Sci Sport Exer 2014; 46: 1928-1935
• 30 Marczak M, Pokorski M. Oxygen breathing and ventilation. J Physiol Pharmacol 2004; 55: 127-134
• 31 Marinovic J, Ljubkovic M, Breskovic T, Gunjaca G, Obad A, Modun D, Bilopavlovic N, Tsikas D, Dujić Z. Effects of successive air and nitrox dives on human vascular function. Eur J Appl Physiol 2012; 112: 2131-2137
• 32 Marinovic J, Ljubkovic M, Obad A, Bakovic D, Breskovic T, Dujić Z. Effects of successive air and trimix dives on human cardiovascular function. Med Sci Sport Exer 2009; 41: 2207-2212
• 33 Marsden KR, Haykowsky MJ, Smirl JD, Jones H, Nelson MD, Altamirano-Diaz LA, Gelinas JC, Tzeng YC, Smith KJ, Willie CK, Bailey DM, Ainslie PN. Aging blunts hyperventilation-induced hypocapnia and reduction in cerebral blood flow velocity during maximal exercise. AGE 2012; 34: 725-735
• 34 Mayer B, Andrew P. Nitric oxide synthases: catalytic function and progress towards selective inhibition. Naunyn-Schmiedebergs Arch Pharmacol 1998; 358: 127-133
• 35 Obad A, Marinovic J, Ljubkovic M, Breskovic T, Modun D, Boban M, Dujić Z. Successive deep dives impair endothelial function and enhance oxidative stress in man. Clin Physiol Funct I 2010; 30: 432-438
• 36 Ogoh S, Ainslie PN. Cerebral blood flow during exercise: mechanisms of regulation. J Appl Physiol 2009; 107: 1370-1380
• 37 Pollock NW. Use of ultrasound in decompression research. Diving Hyperb Med 2007; 37: 68-72
• 38 Rubanyi GM, Vanhoutte PM. Superoxide anions and hyperoxia inactivate endothelium-derived relaxing factor. Am J Physiol 1986; 250: H822-H827
• 39 Sato K, Ogoh S, Hirasawa A, Oue A, Sadamoto T. The distribution of blood flow in the carotid and vertebral arteries during dynamic exercise in humans. J Physiol 2011; 589: 2847-2856
• 40 Smith KJ, MacLeod D, Willie CK, Lewis NCS, Hoiland RL, Ikeda K, Tymko MM, Donnelly J, Day TA, MacLeod N, Lucas SJE, Ainslie PN. Influence of high altitude on cerebral blood flow and fuel utilization during exercise and recovery. J Physiol 2014; 592: 5507-5527
• 41 Smith KJ, Wong LE, Eves ND, Koelwyn GJ, Smirl JD, Willie CK, Ainslie PN. Regional cerebral blood flow distribution during exercise: Influence of oxygen. Resp Physiol Neurobi 2012; 184: 97-105
• 42 Tetzlaff K, Friege L, Koch A, Heine L, Neubauer B, Struck N, Mutzbauer TS. Effects of ambient cold and depth on lung function in humans after a single scuba dive. Eur J Appl Physiol 2001; 85: 125-129
• 43 Thom SR, Milovanova TN, Bogush M, Bhopale VM, Yang M, Bushmann K, Pollock NW, Ljubkovic M, Denoble P, Dujić Z. Microparticle production, neutrophil activation, and intravascular bubbles following open-water SCUBA diving. J Appl Physiol 2012; 112: 1268-1278
• 44 Thom SR, Milovanova TN, Bogush M, Yang M, Bhopale VM, Pollock NW, Ljubkovic M, Denoble P, Madden D, Lozo M, Dujić Z. Bubbles, microparticles, and neutrophil activation: changes with exercise level and breathing gas during open-water SCUBA diving. J Appl Physiol 2013; 114: 1396-1405
• 45 Willie CK, Colino FL, Bailey DM, Tzeng YC, Binsted G, Jones LW, Haykowsky MJ, Bellapart J, Ogoh S, Smith KJ, Smirl JD, Day TA, Lucas SJ, Eller LK, Ainslie PN. Utility of transcranial Doppler ultrasound for the integrative assessment of cerebrovascular function. J Neurosci Methods 2011; 196: 221-237
• 46 Willie CK, Macleod DB, Shaw AD, Smith KJ, Tzeng YC, Eves ND, Ikeda K, Graham J, Lewis NC, Day TA, Ainslie PN. Regional brain blood flow in man during acute changes in arterial blood gases. J Physiol 2012; 590: 3261-3275
• 47 Willie CK, Tzeng YC, Fisher JA, Ainslie PN. Integrative regulation of human brain blood flow. J Physiol 2014; 592: 841-859