title: Subcutaneous tissue gas space pressure during superficial isobaric counterdiffusion.
abstract: Changes in subcutaneous tissue pressure caused by N2O-He, 1-ATA isobaric counterdiffusion gas phase development were measured. Only the ears of New Zealand White rabbits were subjected to counterdiffusion. The rabbits breathed a mixture of 80% N2O-20% O2 while their ears alone were surrounded by He and the rest of their bodies continued to be surrounded by air. Subcutaneous pressure changes were transmitted to the transducer-recorded system via a fluid-filled subcutaneous needle. When the gas phase developed in subcutaneous tissue, pressure rose and a maximum pressure (Pmax) was reached. Pmax in the counterdiffused ear was 48 +/- 10 (SD) Torr, and mean time to reach Pmax was 75 +/- 10 (SD) min. The findings are discussed in relation to the pathological processes of isobaric inert gas counterdiffusion.
mesh_terms: D000818:Animals; D001274:Atmospheric Pressure; D004058:Diffusion; D005260:Female; D006371:Helium / Q000009:adverse effects*; D009609:Nitrous Oxide / Q000009:adverse effects*; D010100:Oxygen / Q000009:adverse effects*; D011817:Rabbits; D012871:Skin Diseases / Q000209:etiology*
chemical_list: D006371:Helium; D009609:Nitrous Oxide; D010100:Oxygen