Surgery is usually not an emergency, but when there is tracheal deviation, the situation needs careful attention. Thyroid meds like synthroid are unlikely to decrease the goiter but may help keep it from growing.
If there are no current symptoms, then another option would be to consider shrinking the benign non-toxic multinodular goiter with radioactive I-131. First would need to do an I-123 uptake/scan (NOT TECHNETIUM) at least 5 weeks after the CT scan (presuming that used iodinated contrast) to see if the goiter will take up iodine adequately to treat it with I-131.
About 2 of 3 patients respond and the average reduction in goiter volume is 40%. In some cases, I-131 causes scar tissue in/around the thyroid and MAY make future surgeries a little mor complicated (but not impossible in my experience).
In the case of low I-123 uptake, some of us are using thyrogen (off-label indication) to augment the uptake prior to I-131 dose.