title: Reoperative parathyroidectomy: who is at risk and what is the risk?
abstract: BACKGROUND
  Persistent and recurrent hyperparathyroidism necessitate reoperation, which is associated with increased procedure-specific complication rates. The effect of reoperative parathyroidectomy on more generalized outcomes is poorly understood. We sought to determine patient, provider, and perioperative characteristics associated with reoperation, as well as to determine the associated risks.
  
  
  METHODS
  All patients receiving a parathyroidectomy in the American College of Surgeons National Surgical Quality Improvement Program database (2008-2011) were identified. Patients receiving initial parathyroidectomy were compared with those receiving reoperative parathyroidectomy. Descriptive statistics and univariate analyses were performed. Multivariate logistic regression models were developed for significant outcome measures.
  
  
  RESULTS
  Of 9114 parathyroidectomies performed, 8738 (95.9%) were initial and 376 (4.1%) were reoperative. The annual rate of reoperation was 3.6%-4.8%. Patients undergoing reoperative parathyroidectomy were more likely to be obese (48.5 versus 40.0%, P = 0.009) and American Society of Anesthesiologist class 3 (40.7 versus 30.3%, P = 0.001) than patients undergoing initial parathyroidectomy. There was no difference in gender, age, or race. Reoperations had a longer median operative time (101 minimum, interquartile range [IQR] [74-146] versus 76 [55-105], P <0.001) and a longer postoperative length of stay (median days until discharge 1, IQR [1-1] versus 1, IQR [0-1], P <0.001). No difference was found in the rates of mortality and common postoperative morbidity as measured in NSQIP. Patients undergoing reoperation were more likely to be readmitted within 30 d (12.7 versus 2.6%, P <0.001). After adjusting for confounders, reoperation continued to be significantly associated with readmission (odds ratio 3.82, confidence interval: 1.63-8.97; P = 0.002).
  
  
  CONCLUSIONS
  Obesity and an American Society of Anesthesiologist 3 classification are independently associated with reoperation. Readmission within 30 d is associated with reoperation and is a target for patient education and quality improvement after this procedure.
authors.affiliation: Department of Surgery, University of Pennsylvania, Philadelphia, Pennsylvania. Electronic address: Lindsay.Kuo@uphs.upenn.edu.
authors.forename: Lindsay E
authors.initials: LE
authors.lastname: Kuo
authors.affiliation: Department of Surgery, University of Pennsylvania, Philadelphia, Pennsylvania.
authors.forename: Heather
authors.initials: H
authors.lastname: Wachtel
authors.affiliation: Department of Surgery, University of Pennsylvania, Philadelphia, Pennsylvania.
authors.forename: Douglas
authors.initials: D
authors.lastname: Fraker
authors.affiliation: Department of Surgery, University of Pennsylvania, Philadelphia, Pennsylvania.
authors.forename: Rachel
authors.initials: R
authors.lastname: Kelz
mesh_terms: D015331:Cohort Studies; D006801:Humans; D016015:Logistic Models; D009765:Obesity / Q000150:complications; D016105:Parathyroidectomy / Q000009:adverse effects*; D012086:Reoperation; D012189:Retrospective Studies; D012306:Risk
keywords: ACS NSQIP; Morbidity; Mortality; Primary hyperparathyroidism; Readmission rate; Reoperative parathyroidectomy