Entonox

---

Entonox : 50% O2 + 50% N2O

Labour and Dental analgesia

Poynting effect :
at -6 degree C , the O2 & N2O separate into layers.
So only O2 is delivered 1st and then only N2O -- which leads to hypoxia.

Avoid it by vigorous shaking before use. 

---