title: Can we avoid inadvertent parathyroidectomy during thyroid surgery?
abstract: OBJECTIVE
  To identify risk factors of inadvertent parathyroidectomy (IP) during thyroid surgery with the aim of decreasing the incidence of this unpleasant complication and to evaluate the impact on temporary and permanent hypocalcaemia following bilateral thyroidectomy.
  
  
  METHODS
  All consecutive thyroid surgical procedures performed at the Special Surgical Pathology Department of Padova General Hospital and Padova University during one year (January-December 2005) were retrospectively reviewed. Demographic data as well as data on diagnosis, operative reports, pathology findings, and postoperative serum calcium values were collected. A total of 882 patients (F=685 M=197) were included in the study. The patients were divided into 2 groups: those with IP and those without IP, and their data were compared to find factors affecting the occurrence of IP. The impact of IP on residual early and late postoperative parathyroid function was assessed. Hypercalcaemic (calcium level below 2.10 mMol/L) patients were followed from 1 week to 3 years.
  
  
  RESULTS
  Seventy of 882 patients (7.9%) were found to have IP. In 11 cases (16% of IP cases and 1.2 % of entire series) the parathyroid glands were completely intrathyroidal. The results of bivariate analysis showed young age (p=0.037), malignant disease (p<0.0001), total thyroidectomy with lymph node dissection (p<0.0001), low weight of thyroid specimen (p<0.0001), and non-visualisation of any parathyroid gland at operation (p<0.0001) as predictive factors for IP. Multivariate analysis revealed significant correlation between IP and malignant disease (p=0.004), and between lymph node dissection and permanent postoperative hypocalcaemia (p=0.018). The incidence rate of transient and permanent hypocalcaemia was higher in IP than in those without. The mean diameter of excised parathyroid glands was 3.2 mm, suggesting more extended or difficult surgical procedures.
  
  
  CONCLUSIONS
  IP is not uncommon during thyroidectomy and is associated with a higher, though not statistically significant, incidence of transient and permanent postoperative hypocalcaemia. Malignant disease, lymph node dissection, non-visualization of any parathyroid gland at operation and younger age seem to be risk factors and should be considered by the surgeon. Further efforts must be taken to reduce the incidence beginning by avoiding parathyroid fragmentation.
authors.affiliation: Department of Medical and Surgical Sciences, University of Padova, Padova, Italy.
authors.forename: Nadia
authors.initials: N
authors.lastname: Sorgato
authors.forename: Gianmaria
authors.initials: G
authors.lastname: Pennelli
authors.forename: Isabella Merante
authors.initials: IM
authors.lastname: Boschin
authors.forename: Eric Casal
authors.initials: EC
authors.lastname: Ide
authors.forename: Costantino
authors.initials: C
authors.lastname: Pagetta
authors.forename: Andrea
authors.initials: A
authors.lastname: Piotto
authors.forename: Antonio
authors.initials: A
authors.lastname: Toniato
authors.forename: Gian Luca
authors.initials: GL
authors.lastname: De Salvo
authors.forename: Elif
authors.initials: E
authors.lastname: Hindié
authors.forename: Adil
authors.initials: A
authors.lastname: Al-Nahhas
authors.forename: Domenico
authors.initials: D
authors.lastname: Rubello
authors.forename: Maria Rosa
authors.initials: MR
authors.lastname: Pelizzo
mesh_terms: D000328:Adult; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D010280:Parathyroid Glands / Q000601:surgery*; D016105:Parathyroidectomy