Unintentional parathyroidectomy and postoperative hypocalcaemia. Conventional thyroidectomy versus miniinvasive thyroidectomy

BACKGROUND: Hypocalcemia and unintentional parathyroidectomy would be associated as cause of post-thyroidectomy hypocalcemia. MATERIALS AND METHODS: We analysed the cases treated with total thyroidectomy by two experienced endocrine surgeons from January 2010 to December 2011 at the Unit of General Surgery and Organ Transplantation of the University Hospital of Parma. These cases were divided in two groups: "Group A" included patients for whom a histological report was made that was negative for a parathyroid avulsion, and "Group B" included patients for whom an inadvertent avulsion of the intracapsular parathyroid glands had occurred. RESULTS: In total, 538 patients were treated with a total thyroidectomy from January 2010 to December 2011. In 26 cases, the histological report highlighted the presence of an intracapsular parathyroid gland. The values of pre-operative calcaemia in group A and group B were 9.204 +/- 0.2703 mg/dl versus 9.283 +/- 0.401 mg/dl, respectively (p=0.32). The values of post-operative calcaemia were 8.039 +/- 0.596 mg/dl for group A versus 7.569 +/- 0.618 mg/dl for group B (p=0.0002) In Group A, 91/512 patients were treated with the minimally invasive video-assisted thyroidectomy (MIVAT) technique (17,7%), while 1/26 patients in group B was treated with a MIVAT (3,8%). DISCUSSION: Unintentional parathyroidectomies can occur with experienced surgeons, but this complication is not related to a substantial difference in the incidence of hypocalcemia. MIVAT can helps the endocrine surgeon in the detection of the parathyroids glands, but when the parathyroid is intracapsular, is difficult to preserve it, during surgical dissection.