title: Morbidity following thyroid surgery: does surgeon volume matter?
abstract: OBJECTIVE
  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.
authors.affiliation: Department of Surgery, University Hospital of Salamanca, Paseo San Vicente 58-182, 37007 Salamanca, Spain. crmngs@hotmail.com
authors.forename: Carmen
authors.initials: C
authors.lastname: González-Sánchez
authors.forename: Guzmán
authors.initials: G
authors.lastname: Franch-Arcas
authors.forename: Alberto
authors.initials: A
authors.lastname: Gómez-Alonso
mesh_terms: D002983:Clinical Competence; D015331:Cohort Studies; D013507:Endocrine Surgical Procedures / Q000009:adverse effects* / Q000379:methods; D005260:Female; D013502:General Surgery; D006801:Humans; D006996:Hypocalcemia / Q000453:epidemiology* / Q000209:etiology / Q000503:physiopathology; D007828:Laryngoscopy / Q000379:methods; D008297:Male; D017063:Outcome Assessment, Health Care; D011183:Postoperative Complications / Q000453:epidemiology / Q000503:physiopathology; D010818:Practice Patterns, Physicians'; D011446:Prospective Studies; D011786:Quality Control; D061226:Recurrent Laryngeal Nerve Injuries / Q000453:epidemiology* / Q000209:etiology; D013961:Thyroid Gland / Q000503:physiopathology / Q000601:surgery*; D013965:Thyroidectomy / Q000009:adverse effects* / Q000379:methods; D016896:Treatment Outcome; D016526:Workload / Q000706:statistics & numerical data*