Ketamine is a very safe drug. My guess is in many of these cases the patient was also on some other drugs (prescribed or otherwise), which a) likely contributed

Ketamine is a very safe drug. My guess is in many of these cases the patient was also on some other drugs (prescribed or otherwise), which a) likely contributed to the need for sedation in the first place, and b) contributed to the respiratory arrests. That is, however, only a guess, I obviously have no specific information about these cases (I can speak from personal experience that the vast majority of people I end up sedating have been using drugs or alcohol (off the top of my head I can't actually think of a single exception to that)). A very minor pedantic point... "EMT" generally refers to providers with a few months of training, and a very narrow scope of practice. The providers administering sedatives would be paramedics, who have a couple years of training (the report cited by the article does use the term "EMT" though).