Parathormone Decline Levels Are Better Markers of Symptomatic Hypocalcemia Following Total Thyroidectomy Than Parathormone Alone

Abstract

Background: We aimed to assess the predictive value of the absolute and relative intact parathormone (iPTH) decline levels as reliable markers of postoperative hypocalcemia. Materials & methods: iPTH levels were measured 4 h after surgery and the following morning after surgery (postoperative day 1). iPTH, absolute iPTH decline (ΔPTH) and relative iPTH decline (ΔPTH%) were calculated and correlated with symptomatic hypocalcemia. Results: Of the 95 patients, 20% of patients (n = 19) developed symptomatic hypocalcemia. The ΔPTH (U = 206; p < 0.001) and ΔPTH% (U = 127; p < 0.001) were significantly higher in patients with symptomatic hypocalcemia. A ΔPTH% of 20% (sensitivity of 84%; specificity of 91%); and an absolute iPTH decline of 3.75 pg/ml (sensitivity of 74%; specificity of 87%) were highly predictive of symptomatic hypocalcemia. Conclusion: Postoperative ΔPTH and ΔPTH% have the potential to be predictors of symptomatic hypocalcemia following thyroidectomy and could facilitate a safe early discharge.

Post-thyroidectomy hypocalcemia and related complications

“…In some patients, the manifestations of hypocalcemia are mild and sometimes imperceptible or absent. Some studies described up to 87% of asymptomatic hypocalcemia after total thyroidectomy in which a meticulous dissection of the parathyroid glands was performed (Barbier et al, 2022;Bove et al, 2020;Hanks & Inabnet, 2015;Marino & Sutin, 2012;Rajan et al, 2020) . These studies reported that 83.0% of thyroidectomized patients developed postoperative hypocalcemia, and 13.0% had signs and symptoms, requiring calcium replacement (Barbier et al, 2022;Bove et al, 2020;Hanks & Inabnet, 2015;Marino & Sutin, 2012;Rajan et al, 2020).…”

“…According to their findings, dosage of ionic calcium instead of total calcium increases the accuracy of the results, since patients with other comorbidities and malnourished patients may have hypoalbuminemia and, consequently, alterations in the serum concentration of total calcium (Barbier et al, 2022;Bove et al, 2020;Hanks & Inabnet, 2015;Marino & Sutin, 2012;Rajan et al, 2020). The adjustment of total calcium values based on the albumin concentration may not adequately reflect the ionic calcium concentration, as changes in pH, differences in the albumin-globulin ratio and magnesium concentration may alter these values (Barbier et al, 2022;Bove et al, 2020;Hanks & Inabnet, 2015;Marino & Sutin, 2012;Rajan et al, 2020) . Several studies suggested that ionic calcium levels alone are safe to investigate hypoparathyroidism and that ionic calcium levels can also be correlated with the clinical picture resulting from hypocalcemia, identifying patients at risk (Abdelhamid & Moussa, 2020;Laft, Jawad, & Numan;Thachil, Joseph, & David, 2021).…”