title: An observational study of the influence of "white-coat hypertension" on day-of-surgery blood pressure determinations.
abstract: BACKGROUND
  Because decisions as to what range of intraoperative blood pressure (BP) is consistent with cerebral well-being are often made in reference to "baseline BP," we sought to determine whether day-of-surgery BPs accurately reflect baseline BP, as defined by ambulatory clinic BPs over the preceding 7 months.
  
  
  METHODS
  Consecutive patients (n=101) who were severely hypertensive (Severe-HTN), systolic (S)>160 mm Hg, or diastolic (D)>100 at first operating room BP (1st OR-BP) were identified retrospectively. Two additional groups were formed from patients whose 1st OR-BP was moderately hypertensive (Mod-HTN, systolic BP=140 to 159 and/or diastolic BP=90 to 99; and normotensive, SBP=110 to 139 and DBP<89). 1st OR-BP was compared with: (1) BP before transfer to the OR (Pre-OR-BP); (2) BP during ambulatory evaluation 1 to 30 days preoperatively (Preop-Eval-BP); and (3) Baseline-BP (average of at least 3 ambulatory clinic BPs during the preceding 7 months). Comorbidity data were collected.
  
  
  RESULTS
  For Severe-HTNs, 1st OR-BP, and Pre-OR-BP (expressed as mean arterial pressure) exceeded Baseline-BP by 16.4±11.6 (SD) and 5.2±11.6 (SD), respectively (P<0.05). Preop-Eval-BP was not different from Baseline-BP. For Mod-HTNs, 1st OR-BP exceeded Baseline-BP by 7.4±8.1 (SD) (P<0.05). But, Pre-OR-BP and Preop-Eval-BP did not differ from Baseline-BP. Among normotensives, 1st OR-BP was not different from Preop-Eval-BP or Baseline-BP. Hypertension, number of antihypertensive medications, vascular diagnoses (peripheral, coronary, cerebral), diabetes, and renal disease were more common in the hypertensive groups. The number of antihypertensive medications, a history of coronary disease, and insulin administration were predictors of an increase in 1st OR-BP over Baseline-BP.
  
  
  CONCLUSIONS
  For most patients whose 1st OR-BP is hypertensive, that BP is greater than ambulatory clinic BPs recorded during the preceding 7 months. For most patients with Severe-HTN at 1st OR-BP, day-of-surgery BPs overestimate Baseline-BP and reference to prehospitalization BPs is advisable. When 1st OR-BP is normotensive, that BP usually reflects Baseline-BP.
authors.affiliation: Department of Anesthesiology, The University of California, USA. jdrummond@ucsd.edu
authors.forename: John C
authors.initials: JC
authors.lastname: Drummond
authors.forename: Jacob L
authors.initials: JL
authors.lastname: Blake
authors.forename: Piyush M
authors.initials: PM
authors.lastname: Patel
authors.forename: Paul
authors.initials: P
authors.lastname: Clopton
authors.forename: Gery
authors.initials: G
authors.lastname: Schulteis
mesh_terms: D000368:Aged; D000556:Ambulatory Surgical Procedures; D001794:Blood Pressure / Q000502:physiology*; D015897:Comorbidity; D005260:Female; D005283:Fentanyl; D006801:Humans; D006993:Hypnotics and Sedatives; D008297:Male; D008874:Midazolam; D008875:Middle Aged; D009294:Narcotics; D011229:Preanesthetic Medication; D011300:Preoperative Care; D013514:Surgical Procedures, Operative; D059466:White Coat Hypertension / Q000150:complications / Q000175:diagnosis / Q000503:physiopathology*
chemical_list: D006993:Hypnotics and Sedatives; D009294:Narcotics; D008874:Midazolam; D005283:Fentanyl