title: Does propofol anesthesia affect intraoperative parathyroid hormone levels? A randomized, prospective trial.
abstract: BACKGROUND
  Intravenous propofol (2,6-diisopropylphenol) infusion is used commonly for sedation/anesthesia during operations. Several authors have reported that propofol can interfere with intact parathyroid hormone (PTH) testing in vitro. Therefore, many surgeons avoid propofol during parathyroidectomy.
  
  
  METHODS
  To determine whether propofol affects intraoperative PTH levels in vivo, we randomly assigned 34 patients (80% power; alpha < .05) with secondary hyperparathyroidism to undergo surgery for dialysis access. Patients were assigned randomly to local anesthesia with either propofol (n = 17 patients) or midazolam (n = 17 patients) sedation. PTH values were obtained before the procedure and at 10 minutes and 30 minutes after the start of the propofol or midazolam.
  
  
  RESULTS
  Median preoperative serum PTH and calcium levels were 175 pg/mL (range, 27-2646 pg/mL) and 9.2 mg/dL (range, 8.1-10.8 mg/dL), respectively. There was no statistically significant difference between the PTH levels in the 2 groups at each of our time points. There was also no difference in the percentage of change from baseline in the PTH values between our 2 groups. No patient in either group had a sustained drop in their PTH level of greater than 50%.
  
  
  CONCLUSIONS
  Intravenous propofol infusion does not alter PTH levels significantly during the operation. Therefore, we believe the intraoperative PTH assay can be used safely during propofol sedation when parathyroid surgical procedures are being performed.
authors.affiliation: Department of Surgery, University of Wisconsin Medical School, 600 Highland Avenue, Madison, WI 53792, USA.
authors.forename: Rebecca S
authors.initials: RS
authors.lastname: Sippel
authors.forename: Yolanda T
authors.initials: YT
authors.lastname: Becker
authors.forename: Jon S
authors.initials: JS
authors.lastname: Odorico
authors.forename: Scott R
authors.initials: SR
authors.lastname: Springman
authors.forename: Herbert
authors.initials: H
authors.lastname: Chen
mesh_terms: D018686:Anesthetics, Intravenous; D001166:Arteriovenous Shunt, Surgical; D002118:Calcium / Q000097:blood; D005260:Female; D006801:Humans; D006962:Hyperparathyroidism, Secondary / Q000097:blood* / Q000209:etiology; D008297:Male; D008875:Middle Aged; D016343:Monitoring, Intraoperative; D010281:Parathyroid Hormone / Q000097:blood*; D015742:Propofol; D011446:Prospective Studies; D006435:Renal Dialysis; D051437:Renal Insufficiency / Q000150:complications / Q000601:surgery
chemical_list: D018686:Anesthetics, Intravenous; D010281:Parathyroid Hormone; D002118:Calcium; D015742:Propofol