Comparison Of Proximal Airway Status In Benign Multi-Nodular Goitres Before And After Total Thyroidectomy Using The Profile Of Pulmonary Function Test (PFT)--Spirometry.

Background and Purpose: Pressure symptoms are usually uncommon in multinodular goitre (MNG). Imaging modalities fail to define the functional air flow dynamics of the upper airway. The airway-related changes due to MNG can be understood using a Pulmonary function test (PFT). To address this lacuna, this study was conducted to compare the pulmonary function profile of patients undergoing total thyroidectomy with benign MNGs using a pre-operative and post-operative pulmonary function test using Spirometry and assessing if surgery had an impact on airway status with varying volumes of thyroid gland measured with ultrasound Methods: The study was conducted in a tertiary care centre in South India between 2019-2020. Twenty-five patients with MNG undergoing total thyroidectomy were included in the study population. PFT (Spirometry -- Lung volume & Flow volume loop) was performed preoperatively and was compared with post-operative PFT after 6 weeks of surgery. The desired variables -- Forced Vital Capacity (FVC), Forced expiratory volume in 1 second (FEV1), FEV1 ratio & Peak expiratory flow rate (PEFR) were analysed & interpreted to ascertain changes in respective values attributable to surgery. Results: Mean (MEDIAN)thyroid gland volume(cc) of 25 participants in our study was 50.28 ±50.03. Statistically significant improvement was observed in the FVC (Preoperative mean 2.16 ± 0.59 to post-operative mean 2.43 ± 0.78), FEV1 (1.79 ± 0.53 to 2.07 ± 0.69), PEFR (356.8 ± 101.4 to 388 ± 99.4). However, the change in FEV1/FVC ratio (0.83 ± 0.05 to 0.84 ± 0.05) did not approach statistical significance. The study showed that in patients without restrictive lung disease, there is a statistically significant improvement in airflow dynamics following total thyroidectomy, irrespective of the volume of the gland. Conclusion: Alleviating upper airway obstruction is an important facet of surgical intervention for thyroid disease. Early surgery to prevent progressive worsening of the degree of obstruction should be considered, irrespective of the volume of the thyroid gland for patients with intrathoracic goitre and in cervical MNG with pre-existing airway compromise. [ABSTRACT FROM AUTHOR]