The Association of Discolored Parathyroid Glands and Hypoparathyroidism Following Total Thyroidectomy

It remains uncertain whether a parathyroid gland (PG) that appears darkened or severely bruised but still has an attached vascular pedicle should be left in situ or taken out and auto-transplanted following total thyroidectomy. Our study aimed to examine the impact of discolored PGs (DPGs) on short- and long-term hypoparathyroidism. One hundred and three patients who underwent total thyroidectomy with 4 clearly identified PGs were analyzed. Location (superior/inferior) and color of each PG were recorded. Patients without DPG were grouped into I while those with 1-2 DPGs and a parts per thousand yen3 DPGs were grouped into II and III, respectively. Transient hypoparathyroidism meant adjusted Ca < 2.00 mol/L 24 h after surgery and/or need for supplements. Protracted hypoparathyroidism meant a subnormal PTH at 4-6 weeks and/or supplements > 6 weeks. Permanent hypoparathyroidism meant supplements a parts per thousand yen1 year. Relative to I, group III had greater adjusted Ca drop at postoperative 1-h (p = 0.012), 24-h (p < 0.001) and lower day-1 PTH (p = 0.015). Having a parts per thousand yen3 DPGs (OR 14.00, 95 % CI 1.575-124.474, p = 0.018) was an independent factor of transient hypoparathyroidism. However, permanent hypoparathyroidism rate was higher than in group I than II (p = 0.019). Eight patients (25.8 %) in group I had undetectable day-1 PTH, while none in group III had undetectable day-1 PTH. Graves' disease/toxic goiter (OR 15.166, 95 % CI 2.594-88.661, p = 0.003) and excised gland weight (OR 1.028, 95 % CI 1.010-1.046, p = 0.003) were independent factors of a parts per thousand yen3 DPGs. PG discoloration is associated with transient hypoparathyroidism while normal colored PG with seemingly adequate blood supply does not always imply functionally normal gland. These findings highlights the need for a real-time intraoperative method to assess PG viability.