Late-onset palsy of the recurrent laryngeal nerve after thyroid surgery

A small subset of patients may develop late-onset palsy of the recurrent laryngeal nerve (RLN) after thyroid surgery. However, no conclusive data have been published regarding the incidence of, and possible risk factors for, this complication.

Preoperative, intraoperative and postoperative data from consecutive patients who underwent thyroid surgery at a single centre between 1999 and 2012 were analysed. Late-onset palsy of the RLN was defined as deterioration of RLN function after normal vocal cord function as investigated by routine preoperative and postoperative laryngoscopy.

The cohort included 16 692 patients with 28 757 nerves at risk. Early postoperative palsy of the RLN was diagnosed in 1183 nerves at risk (4·1 per cent), whereas late-onset RLN palsy was found in 41 (0·1 per cent). Late-onset palsy of the RLN was diagnosed after a median interval of 2·5 (range 0·5-12) weeks and nerve function recovered completely in 28 patients after a median interval of 3 months. This recovery rate was significantly lower than that for early-onset RLN palsy: 1068 (90·3 per cent) of 1183 nerves (P < 0·001). No particular risk factor for late-onset RLN palsy was identified.

Late-onset palsy of the RLN was diagnosed in a small subset of patients after thyroid surgery, and recovery of nerve function occurred less frequently than in patients with early-onset RLN palsy.