title: Noninvasive central venous pressure measurement by controlled compression sonography at the forearm.
abstract: OBJECTIVE
  We sought to validate a new noninvasive technique to determine central venous pressure (CVP) using high-resolution compression sonography.
  
  
  BACKGROUND
  Information concerning CVP is crucial in clinical situations, including cardiac failure, volume overload, and sepsis. The measurement of CVP, however, requires puncture of a vein with attendant risk of complication.
  
  
  METHODS
  After a proof-of-concept study in healthy subjects, a prospective blinded evaluation was performed comparing CVP measurement using a central venous catheter with measurement using compression sonography in critically ill (intensive care unit) patients.
  
  
  RESULTS
  In healthy subjects with experimentally induced venous hypertension with a wide range of pressure values, a strong correlation (r = 0.95; p < 0.001) between noninvasive and invasive peripheral venous pressure at the forearm was shown. High interobserver agreement with an intraclass correlation coefficient of 0.988 shows excellent reliability of the system. Noninvasive peripheral venous pressure measurement at the forearm showed a good correlation with CVP in 50 intensive care unit patients with the forearm positioned both below heart level (r = 0.84; p < 0.001) and at heart level (r = 0.85; p < 0.001). The mean difference between invasive and noninvasive measurement was negligible (-0.1 +/- 3.5 cm H2O and -0.7 +/- 3.4 cm H2O, respectively).
  
  
  CONCLUSIONS
  Controlled-compression sonography is a valuable tool for measuring venous pressure in peripheral veins and allows reliable indirect assessment of CVP without intravenous catheterization.
authors.affiliation: Department of Vascular Medicine, University Hospital, Basel, Switzerland. thalhammerc@uhbs.ch
authors.forename: Christoph
authors.initials: C
authors.lastname: Thalhammer
authors.forename: Markus
authors.initials: M
authors.lastname: Aschwanden
authors.forename: Angela
authors.initials: A
authors.lastname: Odermatt
authors.forename: Ulrich A
authors.initials: UA
authors.lastname: Baumann
authors.forename: Stephan
authors.initials: S
authors.lastname: Imfeld
authors.forename: Deniz
authors.initials: D
authors.lastname: Bilecen
authors.forename: Stephan C
authors.initials: SC
authors.lastname: Marsch
authors.forename: Kurt A
authors.initials: KA
authors.lastname: Jaeger
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001795:Blood Pressure Determination / Q000379:methods*; D002496:Central Venous Pressure / Q000502:physiology*; D016638:Critical Illness; D005260:Female; D005542:Forearm / Q000098:blood supply* / Q000000981:diagnostic imaging*; D006801:Humans; D007362:Intensive Care Units; D016014:Linear Models; D008297:Male; D008365:Manometry; D008875:Middle Aged; D011446:Prospective Studies; D015203:Reproducibility of Results; D014160:Transducers, Pressure; D014463:Ultrasonography; D014680:Veins / Q000000981:diagnostic imaging*