Thanks for posting query on healthcare magic
Primary problem of DKA is raised blood sugar, Dehydration
(due to osmotic diuresis as result of raised sugar) and Ketone
Low BUN and creatinine
can not be explained however you may find low creatinine in very low muscle mass
You are right electrolytes like sodium, potassium, phosphorus should be monitored and corrected if low.
in rage 3.7 should be repeated after 3-4weeks
Hope you got the things clear