The Impact of Calcium and Vitamin D Supplementation Prior to Thyroidectomy on Mitigating Postoperative Hypocalcemia

Abstract

Background Hypocalcemia remains the most frequent complication after thyroidectomy. It can either be transient or permanent, and patients often find it unpleasant due to its association with prolonged hospitalization. The objective of this study was to determine the role of preoperative calcium and vitamin D supplementation in preventing hypocalcemia after subtotal/total thyroidectomy. Material and methods This quasi-experimental study was conducted at the Department of General Surgery, Ayub Teaching Hospital, Abbottabad, Pakistan, from January 2023 to July 2023. We utilized non-probability purposive sampling. Patients undergoing total thyroidectomy were recruited and followed until discharge to ascertain outcomes. They were divided into two groups: Group A received vitamin D (200,000 IU) one week preoperatively as single intramuscular dose and calcium (1 gm) orally two times daily for one week preoperatively, while Group B served as the control. Venous blood samples were taken post-surgery, on the second and seventh day and at day 30 to assess hypocalcemia. Chi-square test was employed, comparing hypocalcemia in both groups with a p-value ≤0.05 considered significant. Results One hundred thirty-two patients underwent subtotal/total thyroidectomy, with 46.2% (n = 61) being male and 53.8% (n = 71) female. The mean age of these patients was 37.12 ± 6.22 years, ranging from 20 to 50 years, and 57.6% (n = 76) were aged over 35 years. More than half (55.3%, n = 73) hailed from rural areas, while 4.7% (n = 59) resided in urban locales. Among the patients, 15.9% (n = 21) had a history of diabetes, and 24.2% (n = 32) were hypertensive. The mean body mass index (BMI) was 23.32 ± 2.41 kg/m², with 7.6% (n = 10) classified as obese. The mean preoperative serum calcium level was 9.87 ± 1.07 mg/dL. Postoperatively, the mean serum calcium level was 8.74 ± 0.83 mg/dL. Both Group A (preoperative vitamin D and calcium supplementation) and Group B (control) demonstrated comparable baseline characteristics before undergoing thyroidectomy. The incidence of postoperative hypocalcemia was notably lower in Group A, with only 4.5% (n = 3) experiencing this complication. By contrast, 24.2% (n = 16) of patients in Group B, the control group, developed hypocalcemia (P = 0.001). Conclusion Our study supports the use of preoperative calcium and vitamin D supplementation in patients undergoing thyroidectomy to combat hypocalcemia. The treated group showed significantly lower hypocalcemia compared to the untreated group B. We recommend preoperative calcium and vitamin D supplementation for all thyroidectomy patients to reduce related morbidities and hospitalization duration.

Keywords: postoperative hypocalcemia; quasi-experimental study; serum calcium; thyroidectomy; vitamin d.