title: Effects of propofol on intraoperative parathyroid hormone monitoring in patients with primary hyperparathyroidism undergoing parathyroidectomy: a randomized control trial.
abstract: OBJECTIVE
  Serial measurements of parathyroid hormone (PTH) serum concentrations aid parathyroidectomy surgery. There are concerns that propofol may increase PTH concentrations and/or interfere with PTH assays. The primary purpose of this study is to determine the effects of propofol on PTH concentrations in patients with primary hyperparathyroidism and to determine its effect on PTH assays.
  
  
  METHODS
  Thirty patients with primary hyperparathyroidism were assigned randomly to induction and maintenance with either propofol or sevoflurane. Blood samples for PTH assays were obtained pre-induction, immediately after induction, ten minutes after induction, and after excision of parathyroid adenoma. The primary endpoint was the PTH concentration at ten minutes after induction. This endpoint was compared between groups using analysis of covariance adjusting for pre-induction PTH. An in vitro study was performed with four different pools of PTH concentrations that were spiked with increasing concentrations of propofol. Serum PTH was measured in duplicate in each sample and analyzed using repeated measures analysis of variance.
  
  
  RESULTS
  At ten minutes after induction, PTH concentrations did not differ significantly between groups (least square mean difference -7.0 pg·mL(-1); 95% confidence interval, -34.2 to +20.2). The PTH level in vitro did not change significantly with increasing propofol concentrations.
  
  
  CONCLUSIONS
  Parathyroid hormone concentrations in patients with primary hyperparathyroidism were not affected by the type of anesthesia (propofol vs sevoflurane). Furthermore, propofol was found not to interfere with PTH assays at clinically relevant concentrations. There is no evidence to support the avoidance of a propofol anesthetic for parathyroid surgery.
authors: Department of Anesthesiology, College of Medicine, Mayo Clinic, 200 First Street, SW, Rochester, MN 55901, USA.
authors: Jonathon E
authors: JE
authors: Kivela
authors: Juraj
authors: J
authors: Sprung
authors: Melanie L
authors: ML
authors: Richards
authors: Brad S
authors: BS
authors: Karon
authors: Roger E
authors: RE
authors: Hofer
authors: Lavonne M
authors: LM
authors: Liedl
authors: Liedl M
authors: LM
authors: Liedl
authors: Darrell R
authors: DR
authors: Schroeder
authors: Toby N
authors: TN
authors: Weingarten
mesh_terms: D000328:Adult; D000368:Aged; D018686:Anesthetics, Intravenous / Q000494:pharmacology*; D005260:Female; D006801:Humans; D049950:Hyperparathyroidism, Primary / Q000097:blood / Q000601:surgery*; D008297:Male; D008875:Middle Aged; D016343:Monitoring, Intraoperative; D010281:Parathyroid Hormone / Q000097:blood*; D016105:Parathyroidectomy; D015742:Propofol / Q000494:pharmacology*
chemical_list: D018686:Anesthetics, Intravenous; D010281:Parathyroid Hormone; D015742:Propofol