Can hyperoxia and hyperbaric conditions induce a increase in systemic pressures (SBP, DBP, MAP) to the breathing of 100 percent oxygen at normal and hyperbaric barometric pressure?

The objectives of this study were to assess systolic, diastolic and mean blood pressure (BP) levels with large increases of systemic oxygen while breathing hyperoxic gas. The survey consisted of a repetitive measure of arterial pressure during a standardized compressions in a hyperbaric chamber (absolute pression : 2.8 bars, 41 psi), for 90 minutes while the breathing pure oxygen, with air breaks every 25 minutes to reduce oxygen toxicity, during a hyperbaric oxygen therapy (HBOT). Methods(see fig1)Systolic and diastolic blood pressure (SBP and DBP) were measured by auscultatory method, with calculated mean blood pressure (MBP). 57 volunteer subjects were recruited (mean age : 60.6 years +/− 15.8) Result(see fig2)In normoxia compared with the surface, outside and in the hyperbaric chamber (opened door), all pressures increase (SBP : 7.8%, MBP : 7% and DBP: 10.6%). Theses variations are significant.Effects of depth: In normoxia, compared with the surface, at depth all pressures decreases (SBP : −2%, MBP : ...