Incidental Parathyroidectomy during Thyroidectomy: Risk Factors and Outcomes: A Systematic Review and Meta-Analysis

Abstract Background Thyroidectomy is a widely used and relatively safe procedure having a major postoperative morbidity of less than 5% for experienced surgeons. Major complications include recurrent laryngeal nerve injury, postoperative hemorrhage and hypocalcemia. Aim of the Work It aims to perform a systematic review and meta-analysis of studies and reports to identify the risk factors of IP and the effect of IP on postoperative hypocalcemia during thyroidectomy. Patients and Methods We followed the PRISMA statement guidelines during this systematic review and meta-analysis preparation and performed all steps according to the Cochrane handbook of systematic reviews of intervention. We searched PubMed, Scopus, Cochrane, and Web of Science, Embase, and Science Direct from 2000 till September 2021 relevant keywords. We used the following search strategy for searching different databases: (“incidental parathyroidectomy” OR “unintentional parathyroidectomy” OR “inadvertent parathyroidectomy”, “thyroidectomy” OR “thyroid surgery” OR “thyroid resection” OR “incidental parathyroidectomy” OR “unintentional parathyroidectomy” OR “inadvertent parathyroidectomy”, “thyroidectomy” OR “thyroid surgery” OR “thyroid resection”) AND (“hypocalcemia” OR “low calcium level” OR “hypocalcemia” OR “hypoparathyroidism”). All the references of the included studies were searched for relevant studies. Results Even in the hands of experienced surgeons, incidental parathyroidectomy can occur during any thyroid operation. The incidence of IP in thyroidectomy ranged from 2.9 percent to 51.1 percent, according to the articles included in our review. Postoperatively, 2.2–50.0 percent of incidentally excised parathyroid glands were identified as intrathyroidal, indicating that complete IP elimination is nearly impossible. However, because 16.7–40.0 percent of incidentally excised parathyroid glands were found in an intracapsular location and 15.7–81.1 percent were found in an extracapsular location, more diligent intraoperative identification of the parathyroid gland may reduce the incidence of IP. We found that malignancy, total thyroidectomy, central neck dissection and reoperation are significant risk factors of incidental parathyriodectomy. IP was found to increase the incidence of temporary/ permanent and permanent postoperative hypocalcemia Conclusion Malignancy, total thyroidectomy, central neck dissection, and reoperation are all significant risk factors for IP, according to this meta-analysis. IP was found to increase the incidence of temporary/ permanent and permanent postoperative hypocalcemia.