[The Newell]

If you have medicare and traveling through Canada on your way to Alaska here is what is said:

"You’re traveling through Canada without unreasonable delay by the most
direct route between Alaska and another state when a medical emergency occurs,
and the Canadian hospital is closer than the nearest U.S. hospital that can treat
your illness or injury. Medicare determines what qualifies as “without
unreasonable delay” on a case-by-case basis."

Now I'm not sure the rules and regulation is your visiting Canada only, that is something to find out though.

Joseph