title: Saliva stimulation with glycerine and citric acid does not affect salivary cortisol levels.
abstract: OBJECTIVE
  In critically ill patients with hypotension, who respond poorly to fluids and vasoactive drugs, cortisol insufficiency may be suspected. In serum over 90% of cortisol is protein-bound, thus routine measures of total serum cortisol may yield 'false lows' due to hypoproteinaemia. Thus, the occurrence of cortisol insufficiency could be overestimated in critically ill patients. Salivary cortisol can be used as a surrogate for free serum cortisol, but in critically ill patients saliva production is decreased, and insufficient volume of saliva for analysis is a common problem. The aim of this study was to investigate if a cotton-tipped applicator with glycerine and citric acid could be used for saliva stimulation without affecting salivary cortisol levels.
  
  
  METHODS
  Prospective, observational study.
  
  
  METHODS
  Thirty-six volunteers (six males, 30 females), age 49 ± 9 years, without known oral mucus membrane rupture in the mouth.
  
  
  METHODS
  Forty-two pairs of saliva samples (22 paired morning samples, 20 paired evening samples) were obtained before and after saliva stimulation with glycerine and citric acid. Salivary cortisol was analysed using Spectria Cortisol RIA (Orion Diagnostica, Finland).
  
  
  RESULTS
  The paired samples correlated significantly (P < 0.0001) and there was no significant difference between un-stimulated and stimulated salivary cortisol levels.
  
  
  CONCLUSIONS
  Saliva stimulation with a cotton-tipped applicator containing glycerine and citric acid did not significantly influence salivary cortisol levels in healthy volunteers. This indicates that salivary cortisol measurement after saliva stimulation may be a useful complement when evaluating cortisol status in critically ill patients.
authors: Department of Anaesthesia and Intensive Care, Institution of Surgery and Perioperative Sciences, Umeå University, Umeå, Sweden.
authors: Camilla
authors: C
authors: Brorsson
authors: Per
authors: P
authors: Dahlqvist
authors: Leif
authors: L
authors: Nilsson
authors: Silvana
authors: S
authors: Naredi
mesh_terms: D000328:Adult; D019343:Citric Acid / Q000737:chemistry*; D005260:Female; D005387:Finland; D005990:Glycerol / Q000737:chemistry*; D006801:Humans; D006854:Hydrocortisone / Q000737:chemistry*; D066298:In Vitro Techniques; D008297:Male; D008875:Middle Aged; D011446:Prospective Studies; D012463:Saliva / Q000737:chemistry*
chemical_list: D019343:Citric Acid; D005990:Glycerol; D006854:Hydrocortisone