Separate pre-op and post-op?
You ask: These two are different procedures, so when using modifier 59 with the tonsillectomy shouldn't the insurance pay out the tonsillectomy at 100%?
No, they shouldn't ... because you won't be doing separate pre and post-op care.
Remember, the reimbursement for a surgical procedure inlcudes the pre-op visit (day of or day before surgery, unless Decision for surgery), and post op care. If multiple procedures are performed in the same operative session, the multiple surgery discount will apply, because the pre- and post-op care will be handled together.
F Tessa Bartels, CPC, CPC-E/M