Back in the mid 60’s I was hit just behind my left knee by a big Diamondback, I was given antivenom 4 times. I was lucky in that I had very little tissue damage in spite of the swelling. What I did have was a severe reaction to antivenom and that damn near killed me, my body temperature peaked at 107. This was back when they used horses instead of sheep as they do now. Interestingly enough I was hit again about 15 years latter on the left index finger and experienced swelling only but no damage, also didn’t take any antivenom for that one.
Best advice, call ahead before driving to find a hospital that does carry antivenom and drive the distance required.
I’d steer clear of dusty roads. There was a WWII bomber training base out West of Odessa, Texas just outside Pyote called the Rattlesnake Bomber base. There area was full of rattlers. On cool evenings and days the road from Grand Falls, Texas back to Pyote would be lined with snakes getting warmed by the asphalt.
And that’s why one has to be careful. Most rattlesnake bites particularly in a startle situation are dry bites with little to no venom injected. cro fab is not needed in that situation and can cause it’s own issues. A child is a different story I don’t treat them and don’t know the protocols