As a part of space-research program, a physiologist was asked to investigate the effect of flight-induced stress on blood pressure. Accordingly the blood pressure of the cosmonauts was to be measured twice: Once before the takeoff and once after the spacecraft entered the designated orbit around the earth. For a proper comparison, the preflight blood pressure should be recorded in:
The lying down position
The sitting position
The standing position
Any position, as long as the post - flight recording is made in the same position
Ans. (a) The lying down position(Ref: Guyton, 13th ed/p.566)Gravity factor is totally eliminated in spaceSo, for comparison preflight BP should be taken in the lying down position
Circulation: Arterial Pressure Regulation - Role of Kidney