Under the Sea Ocean Coral 2007 Scuba Snorkel Caribbean 10, originally uploaded by Matt Anderson Photography.
According to recent research from the United States, "Venous gas bubbles occur in recreational SCUBA divers in the absence of decompression sickness, forming venous gas emboli (VGE) which are trapped within pulmonary circulation and cleared by the lung without overt pathology. We hypothesized that asymptomatic VGE would transiently increase ventilation-perfusion mismatch due to their occlusive effects within the pulmonary circulation."
"Two sets of healthy volunteers (n = 11, n = 12) were recruited to test this hypothesis with a single recreational ocean dive or a baro-equivalent dry hyperbaric dive. Pulmonary studies (intrabreath V-A/Q (iV/Q), alveolar dead space, and FVC) were conducted at baseline and repeat 1- and 24-h after the exposure. Contrary to our hypothesis V-A/Q mismatch was decreased 1-h post-SCUBA dive (iV/Q slope 0.023 +/- 0.008 ml(-1) at baseline vs. 0.010 +/- 0.005 NS), and was significantly reduced 24-h post-SCUBA dive (0.000 +/- 0.005, p< 0.05), with improved V-A/Q homogeneity inversely correlated to dive severity. No changes in V-A/Q mismatch were observed after the chamber dive. Alveolar dead space decreased 24-h post-SCUBA dive (78 +/- 10 ml at baseline vs. 56 +/- 5, p< 0.05), but not 1-h post dive. FVC rose 1-h post-SCUBA dive (5.01 +/- 0.18 l vs. 5.21 +/- 0.26, p< 0.05), remained elevated 24-h post SCUBA dive (5.06 +/- 0.2, p< 0.05), but was decreased 1-hr after the chamber dive (4.96 +/- 0.31 L to 4.87 +/- 0.32, p< 0.05)," wrote G.S. Moore and colleagues (see also Angiology).
The researchers concluded: "The degree of V-A/Q mismatch in the lung was decreased following recreational ocean dives, and was unchanged following an equivalent air chamber dive, arguing against an impact of VGE on the pulmonary circulation."
Moore and colleagues published their study in European Journal of Applied Physiology (Ventilation-perfusion inequality in the human lung is not increased following no-decompression-stop hyperbaric exposure. European Journal of Applied Physiology, 2009;107(5):545-552).
For additional information, contact G.S. Moore, 4860 Y St., Suite 2500, Sacramento, CA 95817, USA.
Publisher contact information for the European Journal of Applied Physiology is: Springer, 233 Spring St., New York, NY 10013, USA.
Keywords: City:Sacramento, State:CA, Country:United States, Angiology, Applied Physiology, Pathology, Perfusion
This article was prepared by Biotech Week editors from staff and other reports. Copyright 2009, Biotech Week via NewsRx.com.
"Findings from G.S. Moore and co-researchers advance knowledge in angiology." Biotech Week 23 Dec. 2009: 265. Academic OneFile. Web. 27 Dec. 2009.