title: Accuracy of PTH assay and corrected calcium in early prediction of hypoparathyroidism after thyroid surgery.
abstract: OBJECTIVE
  To evaluate the accuracy of the intraoperative parathyroid hormone (ioPTH) and 6-hour PTH (6hPTH) assay in predicting transient hypoparathyroidism after thyroidectomy.
  
  
  METHODS
  A nonrandomized prospective study was conducted on patients undergoing thyroid surgery.
  
  
  METHODS
  Of 138 patients undergoing thyroid surgery, intraoperative PTH was measured 10 minutes after gland removal. Serum calcium, magnesium, inorganic phosphorus, albumin, and PTH levels were assayed 6 and 16 hours after surgery and daily until patient discharge.
  
  
  RESULTS
  The development of postoperative hypocalcemia was associated with low ioPTH (P < 0.0001) and 6hPTH (P < 0.0001) values, and the decline of PTH from baseline (P < 0.0001). The cutoff for percentage decline of ioPTH and 6hPTH (55.7% and 379%, respectively) was more accurate than an absolute value. Accuracy, and positive and negative predictive values were 88 percent, 63 percent, and 100 percent for ioPTH and 75 percent, 46 percent, and 100 percent for 6hPTH, respectively.
  
  
  CONCLUSIONS
  With the use of ioPTH decline in association with 16-hour corrected calcium, it is possible to distinguish early normocalcemic patients from hypocalcemic ones in most cases.
authors.affiliation: ENT Department, S Orsola-Malpighi Hospital, Bologna University, Bologna, Italy. ocavicchi@libero.it
authors.forename: Ottavio
authors.initials: O
authors.lastname: Cavicchi
authors.forename: Ottavio
authors.initials: O
authors.lastname: Piccin
authors.forename: Umberto
authors.initials: U
authors.lastname: Caliceti
authors.forename: Ignacio Javier
authors.initials: IJ
authors.lastname: Fernandez
authors.forename: Carla
authors.initials: C
authors.lastname: Bordonaro
authors.forename: Domenico
authors.initials: D
authors.lastname: Saggese
authors.forename: Alberto Rinaldi
authors.initials: AR
authors.lastname: Ceroni
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000465:Algorithms; D002118:Calcium / Q000097:blood*; D005260:Female; D006801:Humans; D007011:Hypoparathyroidism / Q000097:blood*; D008297:Male; D008875:Middle Aged; D010281:Parathyroid Hormone / Q000097:blood*; D011183:Postoperative Complications / Q000097:blood*; D011237:Predictive Value of Tests; D011379:Prognosis; D011446:Prospective Studies; D015203:Reproducibility of Results; D013965:Thyroidectomy; D013997:Time Factors
chemical_list: D010281:Parathyroid Hormone; D002118:Calcium