56) BREATHING 100% OXYGEN AT 3 ATMOSPHERES CAUSES

[Editor]

a) increases in PaC02
b) loss of consciousness
c) increased saturation of haemoglobin
d) increased venous oxygen content
e) produces the bends

[Editor]

FFFTF

Breathing 100% oxygen at this pressure would result in 100% saturation of haemoglobin with a small increase in the dissolved content of arterial and venous blood. It would not lead to loss of consciousness, changes in the co2 partial pressure. This may however occur in there was prolonged exposure (24hours) where oxygen toxicity may occur resulting in absorption atelectasis and v/q mismatching. This cannot be interpreted from the question. The bends occurs during rapid ascent from depth when breathing nitrogen containing gas mixtures.