Before surgery there may be some upper airway obstruction. Oh, goiter is an enlargement of the thyroid gland in the neck. I use Tylenol PM to help me sleep, sometimes I just take a half of a caplete. The sedating effects of Tylenol PM works if you are already sleepy. Sleep habits include sleep routine, avoidance of caffeine 6-7 hours before sleep if you are over 40 and the like.
Exercise helps too.
The increase in temperature with exercie if it happens 1-2 hours before sleep can help initiate sleep. The drug seems not to work as well. Pen, you are next. Insomnia is already common in people with chronic illness. The calcium channel blockers can interrupt sleep.