title: Decrease in left ventricular ejection time on digital arterial waveform during simulated hypovolemia in normal humans.
abstract: BACKGROUND
  Left ventricular ejection time (LVET) measured in central arteries is modified during hypovolemia. We compared modifications of the pulse wave in a central artery (carotid) and in a peripheral artery (digital) during central hypovolemia induced by lower body negative pressure (LBNP) in conscious volunteers.
  
  
  METHODS
  Hypovolemia was simulated with progressive LBNP (baseline, -10, -20, and -30 mm Hg) in nine young healthy volunteers. The carotid arterial pressure waveform was recorded using a Millar tonometric method. The digital pulse wave was measured with a volume-clamp method (Finapres) and the stroke volume with a thoracic impedance method (Biomed).
  
  
  RESULTS
  Mean arterial pressure did not change during LBNP. Compared with baseline values, heart rate increased significantly at the -30 mm Hg level (68 +/- 13 beats/min vs. 59 +/- 11 beats/min), and stroke volume decreased as soon as -10 mm Hg was achieved (113 +/- 41 mL vs. 127 +/- 35 mL). Both carotid and digital LVET decreased significantly at the -10 mm Hg level (337 +/- 26 and 339 +/- 24 ms vs. 360 +/- 35 and 361 +/- 24 ms, respectively).
  
  
  CONCLUSIONS
  Peripheral LVET could reflect variation of central LVET during LBNP and be a reliable noninvasive parameter for monitoring hypovolemia.
authors.affiliation: Department of Anesthesiology and UPRES 3540, Hôpital de Bicêtre, Le Kremlin Bicêtre, France.
authors.forename: Thomas
authors.initials: T
authors.lastname: Geeraerts
authors.forename: Pierre
authors.initials: P
authors.lastname: Albaladejo
authors.forename: Adrien Descorps
authors.initials: AD
authors.lastname: Declère
authors.forename: Jacques
authors.initials: J
authors.lastname: Duranteau
authors.forename: Jean-Patrick
authors.initials: JP
authors.lastname: Sales
authors.forename: Dan
authors.initials: D
authors.lastname: Benhamou
mesh_terms: D000328:Adult; D001794:Blood Pressure; D002339:Carotid Arteries; D006801:Humans; D020896:Hypovolemia / Q000503:physiopathology*; D008297:Male; D013318:Stroke Volume; D013997:Time Factors