David Novo
Contributor
While continuing my reading of Deco for Divers, I came across another paragraph that puzzled me:
At a gas switch, the diver then changes from breathing a high helium mix to a high nitrogen mix. The blood quickly carries this nitrogen to the perfused vascular compartment of the inner ear. Here the rapid diffusion of helium from the endolymph and perilymph compartments into the perfused vascular compartment exceeds the transfer of nitrogen in the opposite direction and the washout of helium from the vascular compartment by the blood flow away from the tissue.
Why in this case the diffusion of helium from from the endolymph and perilymph compartments into the perfused vascular compartment exceeds:
1) The transfer of nitrogen in the opposite direction, given that nitrogen is more soluble than helium (and according to Fick's law the rate of diffusion has a direct relationship with solubility)?
2) The washout of helium from the vascular compartment by the blood flow away from the tissue, given that the helium concentration gradient between the vascular compartment and blood is higher than between the former and the other compartments (and according to Fick's law the rate of diffusion has a direct relationship with the concentration gradient)?
Can anyone help me with this?
Thank you.
At a gas switch, the diver then changes from breathing a high helium mix to a high nitrogen mix. The blood quickly carries this nitrogen to the perfused vascular compartment of the inner ear. Here the rapid diffusion of helium from the endolymph and perilymph compartments into the perfused vascular compartment exceeds the transfer of nitrogen in the opposite direction and the washout of helium from the vascular compartment by the blood flow away from the tissue.
Why in this case the diffusion of helium from from the endolymph and perilymph compartments into the perfused vascular compartment exceeds:
1) The transfer of nitrogen in the opposite direction, given that nitrogen is more soluble than helium (and according to Fick's law the rate of diffusion has a direct relationship with solubility)?
2) The washout of helium from the vascular compartment by the blood flow away from the tissue, given that the helium concentration gradient between the vascular compartment and blood is higher than between the former and the other compartments (and according to Fick's law the rate of diffusion has a direct relationship with the concentration gradient)?
Can anyone help me with this?
Thank you.