Morbidity following thyroid surgery: does surgeon volume matter?

PURPOSE

The aim of our study was to analyze the relationship between surgeon volume and morbidity in patients operated on by surgeons with endocrine specialization (EndS group) and those operated on by general surgeons (GenS group) in a single tertiary institution.

METHODS

We present the results of a prospective cohort study of all patients undergoing thyroid surgery in our institution between January 2008 and January 2010, all of whom attended for follow-up for at least 12 months. We assessed pre- and postoperative recurrent laryngeal nerve (RLN) function by laryngoscopy. We monitored serum calcium concentrations in all patients until these values were normal without vitamin D and oral calcium supplementation.

RESULTS

We studied 225 patients: 30 in the GenS group (six surgeons performing <5 procedures per surgeon per year) and 195 in the EndS group (two surgeons performing >40 procedures per surgeon per year). The total number of exposed RLN was 46 and 325, respectively. The incidence of RLN palsy persisting beyond 12 months was higher in the GenS group (2/46 vs. 1/325 exposed RLNs, p = 0.04). The incidence of hypocalcaemia persisting beyond 12 months (bilateral procedures) was also higher in the GenS group (3/16 vs. 3/130 patients, p = 0.028).

CONCLUSIONS

Morbidity in terms of permanent RLN palsy and hypocalcaemia was less frequent among patients operated on by endocrine-dedicated surgeons. Differences in surgical volume and specialized training in neck endocrine surgery may explain these variations in morbidity.