Postoperative hypocalcemia: analysis of factors influencing early hypocalcemia development following thyroid surgery

Abstract

Background: Early Hypocalcemia is the most frequent complication after thyroid surgery. Several studies have tried to identify factors (patient caracteristics or surgical technique variations) affecting hypocalcemia following thyroid surgery. This studiy evaluates the role of several factors in postoperative hypocalcemia development. Methods: A retrospective study conducted on 2108 patients that underwent thyroid surgery in a single center (1669 women and 439 men). Postoperative early hypocalcemia was defined as serum calcium levels lower than 8,0 mg/dl measured 24 h after surgery. Following factors were evaluated in the study: sex, age, glandular hyperfunction, preoperative diagnosis, preoperative serum calcium levels, preoperative serum PTH levels, type of surgery performed (total thyroidectomy vs. lobectomy); minimally invasive video assisted thyroidectomy (MIVAT); number of parathyroid preserved in situ, postoperative serum calcium levels, changes in perioperative calcium levels (difference between preoperative values and postoperative calcium levels), presence of carcinoma in the surgical specimen, presence of thyroiditis based on histopatology reports. Results: Among evaluated factors only gender and surgical procedure revealed to be significantly correlated to early hypocalcemia development. In fact female patients experienced postoperative hypocalcemia in 42% (701/ 1669) of cases, which was signicantly higher than the 21.4% (94/439) identified in men. We also noticed a greater hypocalcemia incidence in patient undergoing total thyroidectomy (38.8%) than in patient undergoing lobectomy group (13.8%). Early hypocalcemia development didn't appear to be related to preoperative serum calcium levels but it showed a statistically significant correlation with perioperative serum calcium level drop. Conclusion: This findings suggest that sex (female gender is a strong risk factor),surgical procedure and perioperative changes in serum calcium are the only factors (among all variables examined) that influence early hypocalcemia development.

The need to give calcium supplementation after total thyroidectomy.

“…11 Transient hypocalcemia is a common disorder that occurred after thyroid surgery, which is defined as decrease the calcium level below the normal during hospital stay and or recovery within 3 months. 12,13 Some authors concluded that PTH at one hour after thyroid resection whether a partial/subtotal thyroidectomy procedure has a predictive power of 94.4%, respective a specificity of 83.6% with a positive value of prediction of 53%, and a negative value of prediction of 98.7%. 14 Moreover, a combination of PTH and calcium assay might be of more accuracy to indicate the need for replacement of calcium, for instance a value of intact PTH one hour post-operative of higher than 10 pg/mL and a total calcium level of higher than 8.5 mg/dL makes calcium replacement unnecessary.…”

The prevalence of hypocalcemia following total thyroidectomy

“…This is in contrast to previous studies, which have shown that patients with malignant conditions are more likely to develop hypocalcemia. 2 , 14 …”

“… 13 However, other studies have illustrated that malignant conditions were more likely to be associated with a comorbid hypocalcemia. 2 , 14 The plausible underlying mechanism might be related to the attachment and fusion of the thyroid capsule and the parathyroid glands, which might be damaged during CCND. 15 …”

VITOM 4K 3D Exoscope: A Preliminary Experience in Thyroid Surgery

“…Post-operative hypocalcaemia has been reported to occur in 23.6% of patients undergoing total thyroidectomy [ 1 ]. As well as causing significant morbidity, hypocalcaemia affects the length of patient stay and necessitates the use of repeated blood tests to guide management [ 5 ]. Therefore, there is a pressing need for surgical technologies that minimise the risk of surgical complications [ 6 ].…”