This is interesting, but doesn't get me too excited. Respiratory depression, whilst a perpetual issue in the the medical use of opioids, isn't necessarily a problem at the lower doses that the evidence suggests actually works. It's a problem at high doses, but those high doses don't provide significant benefits over smaller doses and are associated with hyper-sensitivity to pain and opioid tolerance.

Don't get me wrong though, respiratory depression and arrest is a real thing. I deliberately induce it as part of an anaesthetic every day.