Parathyroid hormone and serum calcium levels measurements as predictors of postoperative hypocalcemia in total thyroidectomy

Mohammed Algarni, Rajab Alzahrani, Gianlorenzo Dionigi, Al-Hakami Hadi, Haia AlSubayea


Background: The rules of quantitative measures such as parathyroid hormone (PTH) levels in the first hours following total thyroidectomy have since been validated repeatedly. Such measures play an integral rule in identifying patients at significant risk for hypocalcaemia and have allowed for earlier supplementation of these patients with calcium with or without vitamin D.
Methods: A retrospective analysis was conducted of 40 consecutive patients with well differentiated thyroid cancer (WDTC) who underwent total thyroidectomy without central neck dissection (CND) as an initial surgery and no comorbidity at King Abdulaziz Medical City (National Guard hospital), between July 2011 and July 2012. A blood testing protocol was applied for all patients that measured serum calcium PTH at
6 hours postoperatively.
Results: Following total thyroidectomy, women were found to experience transient hypocalcaemia in 12.5% of cases (4/32), whereas no men cases encountered this postoperative complication (0/8). However, most probably due to small sample size, this difference was not statistically significant. PTH level was significantly associated with post thyroidectomy hypocalcaemia (43.7±39.3 versus 13.40±24.9 ng/L), P=0.014. Only negligible differences in the length of hospital stay were observed with and without post-thyroidectomy hypocalcaemia.
Conclusions: Using post-thyroidectomy PTH levels to predict hypocalcaemia has been confirmed in the current study. So, the use of PTH levels allows for early risk stratification of our patients and we feel this has resulted in better patient satisfaction.