My sister has been diagnosed with a hiatal hernia. i am very worried about her as she regularly binge drinks and this often causes her to vomit.

You are correct: You are correct to be worried about your sister. Of major concern is the binge drinking. Your sister is fortunate to have you n her life, please continue to encourage her to get help with the drinking problem. Good luck and keep involved as much as possible.

Pancreatitis: More due to alcohol poisoning or alcoholic pancreatitis not due to HH. Vomiting won't make HH worse.