The staggering hypothyroidism in head-and-neck cancer patients after combined multimodality treatment: Dealing with the anesthetic dilemma

Background and Aims: Hypothyroidism is common following treatment of head-and-neck malignancy. We aimed to assess the incidence of hypothyroidism in patients posted for operations with a history of radical neck surgeries with or without adjuvant chemoradiotherapy, their requirement of induction agents, hemodynamic changes, and recovery time following general anesthesia. Methods: This was a prospective, nonrandomized single-arm study conducted in 100 patients aged 18–85 years, who were posted for surgery under general anesthesia after 3 months of radical neck surgery with or without adjuvant therapy. All patients received a standardized general anesthesia protocol. Patients were grouped into those having either hypothyroidism or those in the euthyroid state. Results: Seventy-two percent of patients had varying degrees of hypothyroidism. There was significant reduction in heart rate (HR) and mean arterial pressure (MAP) from preinduction values at 1, 3, 5, and 10 min after intubation in patients with hypothyroidism. The reduction in both HR and MAP was significantly pronounced throughout postintubation period in the hypothyroid patients as compared to the patients with normal thyroid function. The mean induction dose of propofol was significantly lesser for hypothyroid patients compared with euthyroid (0.85 ± 0.17 mg/kg vs. 1.62 ± 2.52 mg/kg), with prolonged recovery time. The incidence of hypotension was significantly high among the hypothyroid patients. Conclusion: The incidence of hypothyroidism in patients after radical neck surgery with or without adjuvant chemo-radiotherapy is as high as 72%. These patients required less anesthetic agents for the induction of general anesthesia and developed profound hypotension after induction which persisted after intubation and had a prolonged recovery time.