At the end of anaesthesia after
discontinuation of nitrous oxide and
removal of endotracheal tube, 1000/0
oxygen is administered to the patient to
prevent:
a) Diffusion Hypoxia
b) Second gas effect
c) Hyperoxia
d) Bronchospasm
Correct Answer - A
A i.e. Diffusion Hypoxia
(Ref : Willer 8/e p656, 3401)
On discontinuation of N2O administration, nitrous oxide gas can
diffuse from blood to the alveoli, diluting O2 in the lung.
Produce an effect called “Diffusional hypoxia”.
To avoid hypoxia, 100% O2, rather than air should be administered
when N2O discontinued.