A Comparative Analysis of Hypocalcemia Incidence in Patients Undergoing Thyroidectomy: Ligasure vs Conventional Ligation of Vessels by Knot Tying

Thyroidectomy is surgical removal of all or part of the thyroid gland, which is located in the front of the neck. Depending on how much thyroid tissue is removed, thyroidectomy could be classified into Total thyroidectomy, subtotal thyroidectomy, near total thyroidectomy and lobectomy.

In total thyroidectomy, the entire thyroid gland is removed. In thyroid lobectomy, one lobe of the thyroid gland is removed. In Thyroid lobectomy with isthmectomy, thyroid lobe along with the isthmus is removed. In Subtotal thyroidectomy, a small portion of the thyroid gland is left during the surgery. This portion is near the trachea, parathyroid glands and the recurrent laryngeal nerve. Indications for thyroidectomy are thyroid cancer, MNG, solitary thyroid nodule.

Complications of thyroidectomy include hoarseness or change in voice (33.3%), damage to parathyroid glands causing hypocalcaemia (54.4%), wound infection (3.4%), dysphagia (32.8%). Several risk factors may contribute to the occurrence of post-thyroidectomy complications, including age, gender, enlarged gland size, type of thyroid disease, presence of fibrosis and inflammation, extent of thyroidectomy, and lymph node dissection. Among these complications, hypocalcaemia and recurrent laryngeal nerve injury are the most frequently observed.

The superior and inferior parathyroid glands, located near the thyroid gland, play a vital role in calcium homeostasis by producing parathyroid hormone (PTH), which regulates calcium levels in the bloodstream.

Hypocalcemia, characterized by low serum calcium levels. It is a frequent and significant complication of thyroidectomy due to damage, ischemia, or removal of one or more of the parathyroid glands during surgery. It can be categorized into two main types, transient hypocalcemia and permanent hypocalcemia. The primary difference between these two types lies in the duration. Transient hypocalcemia lasts for 3 months after surgery, while permanent hypocalcemia persists for 3 months or longer after surgery.

To minimize the risk of parathyroid gland damage, various surgical techniques have been developed, including the utilization of energy-based devices such as Ligasure. Ligasure has gained popularity in thyroidectomy procedures due to its potential advantages in terms of precision, hemostasis, and reduced operative time.

Ligasure is a bipolar vascular sealing system utilized to achieve effective control of bleeding and create a bloodless surgical environment. It operates by utilizing an electrical current within the frequency range of 2-4 MHz It induces denaturation of collagen and elastin within the vessels and surrounding tissues. The localized tissue temperatures typically range between 60-100°C, facilitating the fusion of collagen and elastin in the vessel walls. This fusion process creates a durable sealed zone without any carbonization and enables hemostasis in vessels with diameters of up to 7 mm.

Conventional methods of vessel ligation, which involve the use of ties and suture ligatures, have long been employed in most medical centers. While these techniques effectively control bleeding from vessels, they are time-consuming and carry the risk of harming adjacent structures like the recurrent and superior laryngeal nerves. In light of the growing demand for time-saving procedures, particularly in high-volume operating theaters where efficient patient turnover is essential, there is a growing interest in devices or techniques that minimize the reliance on conventional knot-tying or suture ligation for achieving hemostasis. This is particularly important to optimise anesthesia time and improve overall efficiency.

According to a recent study, hypocalcemia occurred in 6.7% of individuals who underwent surgery using the Liga Sure method. In a separate study, 32.4% of patients who had surgery utilising the traditional knot tying technique experienced hypocalcemia.

However, despite the increasing use of Ligasure and other energy devices, there is a paucity of research comparing their efficacy in preventing hypocalcemia after thyroidectomy.

Therefore, this study aims to address the existing gap in knowledge by conducting a comprehensive comparison of the incidence of hypocalcemia in patients undergoing thyroidectomy using Ligasure versus the conventional artery forceps/knot tying technique.