[IntronExon]

Hypothermia. You use far less oxygen if your metabolism has essentially ground to a halt.

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4530563/

https://www.ncbi.nlm.nih.gov/pubmed/24837800

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4322114/