Gas micronuclei that underlie decompression bubbles and decompression sickness have not been identified.

Gas micronuclei that underlie decompression bubbles and decompression sickness have not been identified. Diving Hyperb Med. 2019 Mar 31;49(1):64 Authors: Doolette DJ Abstract Gas micronuclei are gas-filled voids in liquids from which bubbles can form at low gas supersaturation. If water is depleted of gas micronuclei, high gas supersaturation is required for bubble formation. This high gas supersaturation is required in part to overcome the Laplace pressure at the point of transition from dissolved gas to a bubble of perhaps nanometer-scale radius. The sum of gas and vapour partial pressures inside a spherical bubble (Pbub) of radius r exceeds the ambient barometric pressure (Pamb) and is given by the Young-LaPlace equation: Pbub = Pamb + 2γ/r for a bubble not in contact with a solid surface. The second term on the right-hand side is the Laplace pressure across the gas-liquid interface due to surface tension (γ). For instance, for a surface tension characteristic of blood of 0.056 N·m⁻¹, de novo formation of a bubble of r = 10 nm requires gas supersaturation exceeding 2γ/r = 11.2 MPa. However, in humans, detectable venous gas bubbles follow decompression to sea level from as shallow as 138 kPa air saturation, implying gas supersaturation of only a few kPa are required for decompression bubble formation. It is widely accepted that bubbles that form at such low gas supersaturation grow from pre-existing, micron-scale gas micronu...
Source: Diving and Hyperbaric Medicine - Category: Sports Medicine Tags: Diving Hyperb Med Source Type: research