Can’t speak to the ‘or whatever’ as there may be things I know that are truly urgently needed, but blood type isn’t really an example of a phone type emergency.

Ambulances frequently don’t even carry blood, and when they do, they usually have a small amount of O blood. The question of blood type doesn’t even come into play. Similarly at the hospital, while they may prefer to match blood type, they will use O blood at least in the short term, with a blood typing test being a matter of a couple of minutes to get the information directly instead of relying on pulling up and using the emergency contact information. This is assuming their medical record doesn’t just already have the information.

As said, I try to be available, but it’s largely ruined by the volume of bullshit calls making it impossible to be at the beck and call of any random caller while also living a vaguely sane lifestyle. So I’ll usually send to voicemail unless it’s someone I actually recognize that I know will only call over an urgent matter.