1.1 Thyroid Surgery: Paradigm Shift in Surgical Strategy and Change in Resection Procedure Over the Last 30 Years
In the last 30 years, the surgical strategy in thyroid surgery has changed significantly. This is due to a new endocrine understanding of the various forms of thyroid disease, advances in morphological, functional, and immunological diagnostics, and also the development of surgical techniques, which have led to a reduction in procedure-specific complications (28).
For benign goiter, subtotal resection was long considered the standard procedure, where a "thumb-sized" remnant of thyroid tissue was left in situ. A subtle depiction of the vocal cord nerve and the parathyroid glands seemed unnecessary, as the resection line was at a safe distance from these structures. Complications such as recurrent laryngeal nerve palsy and postoperative hypoparathyroidism were believed to be largely avoidable.
However, subtotal resections have high recurrence rates of up to 40%, making the need for more radical resection obvious, which inevitably led to the development of modern surgical techniques with visualization of the vocal cord nerve and parathyroid glands to avoid a high rate of serious complications (1, 3).
In addition to the perfection of nerve preparation techniques, improved diagnostics of thyroid diseases have taught that for definitive healing of a disease, (almost) total thyroid removal is often required. In multinodular goiter, the thyroid is often nodular throughout, so no healthy tissue can be left in situ. In Graves' disease, the entire thyroid tissue is often subject to increased stimulation, so that remaining tissue often leads to renewed hyperfunction.
In thyroid carcinoma, total removal soon became the standard procedure, thus requiring subtle preparation of the vocal cord nerve and parathyroid glands, often performed with microsurgical techniques.
The trend towards more radical resection forms is shown by Dralle, University Clinic Halle an der Saale, where the proportion of total lobectomies for benign goiter increased from 20% to 70% within 13 years from the mid-1990s (20).
The immediate consequence of increasingly radical primary interventions was the declining number of reoperation interventions, which can be seen as confirmation of the paradigm shift.
1.2 Intraoperative Neuromonitoring (IONM)
Intraoperative neuromonitoring in thyroid surgery is a reliable tool for locating the recurrent laryngeal nerve. When performed correctly, the intraoperative functional testing of the nerve shows good agreement with the postoperative laryngoscopy-controlled vocal cord function. The negative predictive value (unremarkable nerve stimulation = no recurrent laryngeal nerve palsy) is between 92 and 100%, and the positive predictive value (prediction of recurrent laryngeal nerve palsy) is between 35 and 92%. Neuromonitoring increases the identification rate and preservation of the nerve and thus enables the required radicality (total instead of subtotal resection), improves preparatory safety in challenging situations (carcinoma, recurrence), and allows guideline-compliant surgery.
Since the use of intraoperative neuromonitoring, the frequency of recurrent laryngeal nerve palsy in thyroid surgery has declined. An evidence-based improvement was only observed in reoperation surgeries, where the rate of permanent recurrent laryngeal nerve palsy has decreased from 6.6% to 2.2% over the past 15 years. In primary surgeries, the complication rate regarding recurrent lesions is now very low due to the consistent visualization of the recurrent laryngeal nerve per se.
Literature: 3, 4, 12, 21, 29, 30, 47
1.3 Outpatient Thyroid Surgery
In the era of shortened postoperative hospital stays, there are also approaches in thyroid surgery to perform procedures on an outpatient basis. In view of the procedure-specific complication "postoperative bleeding," the data speaks against "one-day surgery."
Most postoperative bleedings occur within the first 6 hours after the procedure. Burkey (5) reports that 19% of patients showed the first signs of postoperative bleeding only after 24 hours, Sonner (44) describes in a prospective study that 54% of all patients in thyroid and parathyroid surgery experience nausea and vomiting more than 24 hours postoperatively and are at increased risk of postoperative bleeding during this phase. Marohn (39) and McHenry (40) also emphasize the need for surgical revisions due to postoperative bleeding beyond the 24-hour mark. Clark (13) notes that about 25% of postoperative bleedings after thyroidectomies can occur up to 24 hours and later after the procedure. Data from Dralle (22) show that in 20% of cases, postoperative bleedings occur later than 24 hours postoperatively.
Based on the data, "one-day surgery" in thyroid surgery is unsafe and not recommended.