Monitoring May Reduce Nerve Injury Risk in Thyroidectomy

Thyroidectomy patients with larger lesions requiring neck dissection or who require postoperative drain use or suffer from postoperative hypocalcemia are more likely to experience recurrent laryngeal nerve injury than thyroidectomy patients without these risk factors, data from a new study suggest.

The results of the study — presented at the American Academy of Otolaryngology–Head and Neck Surgery 2024 Annual Meeting — also showed that intraoperative nerve monitoring was associated with a lower risk for nerve injury.

Thyroidectomy is common and performed on thousands of patients in the United States each year, however, nerve injury remains “a feared complication,” Ryland Spence, a medical student at Brown University, Providence, Rhode Island, and colleagues noted in their abstract.

These findings suggest that nerve monitoring should be considered in all thyroidectomy procedures, especially in those with larger and more complex lesions, the researchers concluded.

The protective association with nerve monitoring was interesting given the ongoing debate about monitoring, including cost-effectiveness, said Mark Swanson, MD, head and neck surgeon with Keck Medicine of USC, Los Angeles, who was not involved with the study.

The new study adds support to the benefits, but previous large studies on nerve monitoring have been inconsistent, he told Medscape Medical News.

Study Details

To better characterize factors associated with nerve injury in thyroidectomy patients, Spence and colleagues reviewed data from the National Surgical Quality Improvement Program database from 2017 to 2021. They examined the association between recurrent laryngeal nerve injury and 18 perioperative factors.

The study population included 31,605 adults. Overall, the preoperative factors of surgical indication, T stage, nodal status, M stage, biopsy result, neoplasm and neoplasm type, and multifocality were significantly associated with an increased risk for recurrent laryngeal nerve injury or dysfunction. The strongest of these were clinical toxicity, neoplasm, and M stage (odds ratios [ORs]: 0.95, 1.16, and 2.33, respectively).

As forintraoperative factors, neck dissection was significantly associated with recurrent laryngeal nerve injury or dysfunction (OR, 1.31).

However, patients who had nerve monitoring during surgery were significantly less likely to have recurrent laryngeal nerve injury or dysfunction than patients without such monitoring (OR, 0.89).

All available postoperative factors including any postoperative hypocalcemia, clinically severe hypocalcemia, neck hematoma/bleeding, and drain use were significantly associated with nerve injury or dysfunction (all P

The ORs for recurrent laryngeal nerve injury for patients with any hypocalcemia, 30-day hypocalcemia, clinically severe hypocalcemia, and drain use were 2.39, 2.21, 2.15, and 1.57, respectively, they added.

The study design prevented conclusions about causality.

Data Can Inform Patient Discussions

Thyroid nodules, and therefore thyroid surgeries, are extremely common; however, this surgery carries morbidity, and nerve injury is always a concern, Swanson confirmed.

Many of the findings of the current study were intuitive but “understanding the risk factors associated with nerve injury can help us counsel patients,” he said.

In practice, although the findings indicate associations rather than causations, the data suggest that patients with more aggressive thyroid cancers are at an increased risk for nerve injury, which can inform shared decision-making, he said.

Limitations included those inherent in a database study, Swanson told Medscape Medical News. Such studies are valuable, as they provide a large patient population, but data can be heterogenous or incompletely collected, he noted. Another limitation was that the current study did not focus on one specific variable, he added.

Looking ahead, more research is needed to hone in and dig deeper on why certain variables caused increased injury, Swanson said.

The study received no outside funding. The researchers had no financial conflicts to disclose. Swanson had no financial conflicts to disclose.