Can hypocalcemia occur In the early postoperative period be predict in total thyroidectomy patients? A prospective study

Abstract

One of the most important complications following total thyroidectomy is hypocalcemia. Although 1 to 2% of these are permanent, the rate of temporary hypocalcemia is quite high. In various studies this rate is re-ported as 10-40%. Therefore, prevention and early diagnosis of hypocalcemia is important. Serum phosphate responds rapidly to changes in circulating PTH levels, and its measurement is readily available in all hospitals. The aim of this study is to compare the value of phosphate measures, which may predict the development of hypocalcemia in the early post operative period following total thyroidectomy, to iPTH and Ca measurements. In this prospective study, patients who underwent total thyroidectomy in our clinic in a one year, inde-pendent of diagnosis were included in a consecutive manner. Calcium measurements were made immediately when symptoms of hypocalcemia developed or 24 hours postoperatively in symptom free patients and at day 5 postoperatively to evaluate late hypocalcemia. In our study calcium levels under 8 mg/dl were accepted as hypocalcemia and iPTH levels less than 10 pg/dl were accepted as below normal levels. 120 patients who underwent total thyroidectomy in our clinic were included in this study. The hypocal-cemic group included 4 patients with hypocalcemia occurring in the first 24 hours post op, 31 patients at 24 hours and 9 cases were hypocalcemia occurred 5 days postop after the patients had normal calcium and were discharged from the hospital. The normocalcemia group had 76 patients (63,33). Temporary hypocalcemia occurs in 10% to 40% of patients after total thyroidectomy. The main ac-cepted reason of this situation that occurs following thyroidectomy is parathyroid insufficiency. Even though one of the important goals in modern thyroid surgery is protecting the functions of the parathyroid glands, hy-pocalcemia following thyroidectoy remains a problem. For this reason, detecting patients that may become hypocalcemic in the postoperative early phase and preventing its occurrence with appropriate treatment will decrease the post operative duration of hospitalization. This being the case, it has made us think that phosphate may be a usable measure to detect post thyroidectomy hypocalcemia earlier. In light of our findings, we suggest that phosphate levels measured in the early postoperative phase of total thyroidectomy, can be used to predict the development of hypocalcemia.

Keywords

• Hypocalcemia
• Thyroidectomy
• Phosphate

References

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