Hopeful Waiting Before Disappointment: Vocal Cord Paralysis After Thyroidectomy

Use of Prophylactic Steroids to Prevent Hypocalcemia and Voice Dysfunction in Patients Undergoing Thyroidectomy: A Randomized Clinical Trial

Importance

Total thyroidectomy is associated with risks related to temporary hypocalcemia and vocal quality dysfunction. Dexamethasone has been proposed to have a physiological effect on hypocalcemia and voice quality.

Objective

To assess the effect of preoperative dexamethasone used to improve hypocalcemia and postthyroidectomy voice dysfunction.

Design, Setting, and Participants

This double-blind, parallel-group, placebo-controlled randomized clinical trial was conducted from January 15, 2014, to December 31, 2019, at the Department of Surgery, Holy Family Hospital in Rawalpindi, Pakistan. All patients with a benign thyroid condition and no preoperative corrected hypocalcemia and voice or vocal quality dysfunction were included. Patients were excluded if they had previous thyroid or neck surgery, known vocal cord dysfunction on laryngoscopy, hearing or voice problems, a history of gastroesophageal reflux, stomach ulcer disease, or contraindications to steroid use.

Interventions

Corrected serum calcium levels and Voice Analog Score defined and measured preoperatively. The dexamethasone group received a 2-mL intravenous dose of 8 mg of dexamethasone 60 minutes before the induction of anesthesia. In contrast, the placebo group received 2 mL of intravenous normal saline (0.9%) 60 minutes before the induction of anesthesia.

Main Outcomes and Measures

Evidence of hypocalcemia and voice dysfunction. Voice dysfunction was defined as a subjective score of less than 50 on a Voice Analog Score scale of 0 to 100 points.

Results

A total of 192 patients (mean [SD] age, 38.9 [12.4] years; 156 women [81.2%]) were included in the study, with 96 patients randomized to each study group (dexamethasone group, mean [SD] age, 39.2 [12.1] years; 75 women [78.1%]; placebo group, mean [SD] age, 38.5 [12.9] years; 81 women [84.5%]). In the first 24 hours after undergoing thyroidectomy, 47 patients (24.4%) developed hypocalcemia and 18 (9.4%) were symptomatic. At 3 days postthyroidectomy, 4 of 96 patients (4.2%) in the placebo group had hypocalcemia compared with no patients in the dexamethasone group. At 24 hours postthyroidectomy, 8 of 96 patients (8.3%) in the dexamethasone group had voice dysfunction compared with 32 of 96 patients (33.3%) in the placebo group. A total of 40 patients (20.8%) reported voice dysfunction. The absolute reduction in the rate of hypocalcemia at 24 hours was 24% (95% CI, 11.9%-35.2%) and at 3 days was 4.2% (-0.44% to 10.0%). The rate of symptomatic hypocalcemia was 19% lower in the dexamethasone group than in the placebo group (95% CI, 11.1%-27.7%). The rate of voice dysfunction was 25% lower in the dexamethasone group than in the placebo group (95% CI, 13.7%-35.7%).

Conclusions and Relevance

In this randomized clinical trial, a single preoperative dose of dexamethasone was safe and effective in reducing postoperative hypocalcemia and voice dysfunction rates in patients undergoing thyroidectomy.

Trial Registration

ClinicalTrials.gov identifier: NCT04752852.