title: Automatic blood pressure monitors. Evaluation of three models in volunteers.
abstract: OBJECTIVE
  Since 1903, blood pressure has been noninvasively monitored (NIBP), either with manual sphygmomanometer or automated noninvasive devices. One NIBP measurement problem is the considerable variance in blood pressure data, both within and between available techniques. The oscillometric method for NIBP monitoring evaluates blood pressure during cuff deflation. Difficulties in blood pressure measurement by oscillometry may arise from: inadequate cuff size, inadequate cuff application, undetected fails in cuff, hoses, or connectors, arm movement, shock and vascular compression proximal to the cuff. This study aimed at evaluating the reliability of three noninvasive blood pressure monitoring devices during five measurements.
  
  
  METHODS
  Blood pressure of 60 healthy female volunteers aged 20 to 40 years was evaluated from 7 am to 11 am, in the sitting position during a normal workday. Five measures were taken with each device at 2-minute intervals. Three automatic blood pressure monitors were studied. No patient was obese, hypertensive or suffering from cardiac disease and cardiac arrhythmia. Indirect measurements were made according to manufacturers' instructions.
  
  
  RESULTS
  There were no differences in demographics among the three studied groups. Mean intrapersonal variation from one measurement to the other was up to 6.7 mmHg for systolic blood pressure (SBP), 4.9 mmHg for mean blood pressure (MBP) and 3.3 mmHg for diastolic blood pressure (DBP) with 95% confidence interval. The highest difference between measures in the same volunteer was 49 mmHg for SBP, 46 mmHg for MBP and 28 mmHg for DBP.
  
  
  CONCLUSIONS
  This study has shown significant variations in SBP, MBP and DBP and that SBP is the most reliable parameter to check blood pressure changes in volunteers.
authors.affiliation: Instituto de Anestesia Regional, Hospital de Base da FAMERP, Faculdade de Medicina de São José do Rio Preto, SP (FAMERP). imbelloni@openlink.combr
authors.forename: Luiz Eduardo
authors.initials: LE
authors.lastname: Imbelloni
authors.forename: Lúcia
authors.initials: L
authors.lastname: Beato
authors.forename: Ana Paula
authors.initials: AP
authors.lastname: Tolentino
authors.forename: Dulcimar Donizete
authors.initials: DD
authors.lastname: de Souza
authors.forename: José Antônio
authors.initials: JA
authors.lastname: Cordeiro