Hi Ammara,
Usually in countries like America and UK you have a lot of scope in doing correspondence in anesthetic medicine. Also there are a lot of good universities offering these correspondence courses along with jobs as anesthetic nurses. But in India it's not the case. I would recommend you to pursue a degree in anesthetic medicine from a college rather than distance learning and correspondence. It will benefit you a lot. Also there are no good colleges in india that offer correspondence or distance learning in anesthetic medicines. If you need anything else do comment.
Good luck