N2O and Opiates Causing Breathing Constriction

[UnregisteredA56]

How safe is this combination regarding the constriction of airways. With proper oxygen, do they still restrict breathing? ive found this nowhere on a network. Is it possible to forward?

 

[Unregist]

^This is the only information I know of, sorry. Ive tried it with not too much interference.

http://www.ncbi.nlm.nih.gov/m/pubmed/7617673/