Is Preoperative Ultrasonographic Thyroid Gland Volume a Good Predictor of Postoperative Complications in Thyroidectomy?: A Prospective Cohort Study

Abstract

Introduction: Thyroidectomy is a commonly performed surgical procedure, especially in areas with a high prevalence of thyroid disorders. Accurate estimation of thyroid volume is crucial for evaluating and managing these conditions, as thyroidectomy in patients with enlarged thyroids can lead to specific concerns regarding optimal preoperative, intraoperative, and postoperative care. Aim: To assess the relationship between thyroid volume and thyroidectomy complications, specifically Vocal Cord Paralysis (VCP) and hypocalcaemia, using preoperative ultrasound and ellipsoid volumetric analysis. Materials and Methods: A prospective cohort study in the General Surgery ward at a Government Medical College, Kottayam, Kerala, India. A total of 70 patients (64 females and six males) with benign thyroid swelling underwent total Thyroidectomy between June 2020 and December 2020. Follow- up was conducted for one year until December 2021. Thyroid gland volume was assessed using ultrasound and calculated using the ellipsoid formula. Based on volume, patients were classified into two groups: 1) <50 mL (mild enlargement), and 2) >50 mL (moderate to severe enlargement). Preoperative examination of vocal cords was performed by the Department of Otorhinolaryngology. Serum calcium levels were measured 48 hours postoperatively, or earlier if symptomatic. Hypocalcaemia was defined as corrected calcium <8.4 mg/dL. The association between thyroid gland volume and complications was analysed to determine if volume could be an effective factor in patient morbidity. Data were entered into Microsoft Excel and analysed using Statistical Package for the Social Sciences (SPSS) version 16.0. Chi-square test was used for qualitative analysis, with a significance level set at p<0.05. Results: The mean thyroid volume for patients with volumes <50 mL and >50 mL was 26.9 mL and 103.2 mL, respectively. Temporary hypocalcaemia (resolving within six months) was significantly higher in patients with volumes <50 mL (p=0.044). Temporary VCP was significantly more frequent in patients with larger volumes (p=0.027). No intraoperative complications were observed in the present study. Conclusion: Thyroid gland volume appears to be an important factor influencing thyroidectomy complications. Smaller thyroid volumes are associated with an increased risk of postoperative hypocalcaemia, while larger volumes are associated with a higher risk of VCP.