title: Assessment of salivary amylase as a stress biomarker in pregnant patients.
abstract: BACKGROUND
  Chronic stress during pregnancy has been associated with worsened maternal and fetal outcomes. Acute stress immediately before spinal anaesthesia for caesarean section may contribute to hypotension. Therefore objective measures of acute stress may help identify women at risk of adverse outcomes. Salivary alpha-amylase is a stress biomarker that has so far been poorly investigated during pregnancy. The reference change value is the difference between two sequential results that must be exceeded for a change to be considered clinically relevant. Our first aim was to determine if salivary alpha-amylase increased in pregnant patients when subjected to the stress of transfer to the operating room. Our second aim was to determine if changes in salivary alpha-amylase were likely to be clinically significant by measuring reference change value in healthy volunteers.
  
  
  METHODS
  In 15 pregnant patients undergoing planned caesarean section under spinal anaesthesia, salivary alpha-amylase, systolic blood pressure, heart rate, and immediate anxiety were measured on the morning of surgery on the ward and again in the operating room. The reference change value was calculated from 18 healthy volunteers.
  
  
  RESULTS
  A median 220% increase in salivary alpha-amylase activity (P=0.0015) and a 17% increase in systolic blood pressure (P=0.0006) were observed between the ward and operating room. No changes of immediate anxiety or heart rate were observed. Reference change value was ±76% in volunteers and 13 of the 15 pregnant patients had a salivary alpha-amylase increase greater than the reference change value.
  
  
  CONCLUSIONS
  When pregnant women are taken to the operating room, a clinically and statistically significant increase in salivary alpha-amylase was observed. Further studies are required to define its clinical usefulness.
authors: Département d'Anesthésie, Hôpital Bichat-Claude Bernard, Assistance Publique-Hôpitaux de Paris, Université Paris 7, Paris, France. jean.guglielminotti@bch.aphp.fr
authors: J
authors: J
authors: Guglielminotti
authors: M
authors: M
authors: Dehoux
authors: F
authors: F
authors: Mentré
authors: E
authors: E
authors: Bedairia
authors: P
authors: P
authors: Montravers
authors: J-M
authors: JM
authors: Desmonts
authors: D
authors: D
authors: Longrois
mesh_terms: D000328:Adult; D015415:Biomarkers / Q000032:analysis; D005260:Female; D006339:Heart Rate; D006801:Humans; D008875:Middle Aged; D011247:Pregnancy; D011248:Pregnancy Complications / Q000175:diagnosis* / Q000201:enzymology; D012463:Saliva / Q000201:enzymology*; D013315:Stress, Psychological / Q000175:diagnosis* / Q000201:enzymology; D013599:Systole; D000516:alpha-Amylases / Q000032:analysis*
chemical_list: D015415:Biomarkers; D000516:alpha-Amylases