I don’t mean to disparage the discovery, just the assertion.
For example, there are now “blood therapeutics”, blood substitutes that when injected, contain so much oxygen that the time to the start of oxygen deprivation damage is extended from a few minutes to almost a half an hour.
Likewise there is now a means to aerate blood with micro bubbles of oxygen, so even with minimal circulation, such as with crush injuries, enough oxygen is delivered to stave off additional tissue damage.
Blood coagulation technology has had several breakthroughs, so that even a lot of arterial bleeding can be limited.
Then there are technologies like Accuvein:
There are also very small portable vital signs and even anesthesia monitors.