Summary This randomised, double‐blinded, controlled trial was designed to identify the optimal dose of remifentanil for cough suppression without adverse effects during emergence from sevoflurane‐remifentanil anaesthesia for thyroidectomy. One hundred and four patients were randomly assigned to maintain target effect‐site concentrations of remifentanil at 0 (control group), 1.0 (remifentail 1 group), or 1.5 ng.ml−1 (remifentanil 1.5 group) during emergence. The incidence of coughing was lower in the remifentanil 1.5 group (31%) than in the control group (74%) or remifentanil 1 group (63%) (p = 0.0004). In addition, the severity of coughing during extubation was lower in the remifentanil 1.5 group (median (IQR [range]) 0 (0–1 [0–1]) than in the control group (1 (0–2 [0–3])) and remifentanil 1 group (1 (0–2 [0–3])) (p = 0.004). Haemodynamic changes were reduced, but emergence time and stay in the post‐anaesthesia care unit was prolonged in the remifentanil 1.5 group. Maintaining the remifentanil effect‐site concentration at 1.5 ng.ml−1 during emergence from sevoflurane‐remifentanil anaesthesia reduces the incidence and severity of coughing without serious adverse events and may provide haemodynamic stability in patients undergoing thyroidectomy. However, awakening may be delayed.

Clinicaltrial.gov identifier: NCT01897337.