title: Pleth variability index predicts fluid responsiveness in mechanically ventilated adults during general anesthesia for noncardiac surgery.
abstract: OBJECTIVE
  To investigate whether the pleth variability index (PVI), derived noninvasively from a pulse oximeter probe, would predict fluid responsiveness in patients undergoing noncardiac surgeries.
  
  
  METHODS
  A clinical, prospective, observational study.
  
  
  METHODS
  Operating room of a tertiary care hospital.
  
  
  METHODS
  Twenty-nine adult patients undergoing a range of noncardiac surgeries, requiring general anesthesia, tracheal intubation, and mechanical ventilation.
  
  
  METHODS
  Intravenous volume expansion with 500 mL of colloid following induction of general anesthesia and after a period of hemodynamic stability before the start of surgery.
  
  
  RESULTS
  Baseline values for PVI and stroke volume index, derived from an esophageal Doppler monitor, were compared with final values after the volume expansion. Patients were classified into fluid responders and nonresponders based on a stroke volume index increase of ≥ 10%. The optimal cut-off value for baseline pleth variability index for predicting fluid responsiveness was determined. There were 17 responders (59%) to the 500-mL volume expansion. Baseline PVI value was significantly different between responders and nonresponders (16.5 ± 6.4% v 10.3 ± 2.7%; p = 0.004). Receiver operating characteristic analysis demonstrated significant predictive ability of an increase in stroke volume index for PVI with area under the curve of 0.84 (95% confidence interval = 0.69-0.99). The optimal cut-off value for baseline PVI was 10.5%, with a sensitivity of 88% and a specificity of 67%.
  
  
  CONCLUSIONS
  Pleth variability index is predictive of fluid responsiveness in adult patients undergoing noncardiac surgery.
authors.affiliation: Department of Anaesthesia, Box Hill Hospital, Box Hill, Victoria, Australia. Electronic address: andy.siswojo@gmail.com.
authors.forename: Andy Sisnata
authors.initials: AS
authors.lastname: Siswojo
authors.affiliation: St. Vincent's Hospital, Fitzroy, Victoria, Australia.
authors.forename: Daniel Mun-Yen
authors.initials: DM
authors.lastname: Wong
authors.affiliation: St. Vincent's Hospital, Fitzroy, Victoria, Australia.
authors.forename: Tuong Dien
authors.initials: TD
authors.lastname: Phan
authors.affiliation: St. Vincent's Hospital, Fitzroy, Victoria, Australia.
authors.forename: Roman
authors.initials: R
authors.lastname: Kluger
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000768:Anesthesia, General / Q000379:methods*; D005260:Female; D005440:Fluid Therapy / Q000379:methods*; D006801:Humans; D007430:Intraoperative Care / Q000379:methods*; D008297:Male; D008875:Middle Aged; D016343:Monitoring, Intraoperative / Q000379:methods; D010092:Oximetry / Q000379:methods* / Q000706:statistics & numerical data; D010991:Plethysmography / Q000379:methods / Q000706:statistics & numerical data; D011446:Prospective Studies; D012372:ROC Curve; D012121:Respiration, Artificial / Q000379:methods*; D013514:Surgical Procedures, Operative; D055815:Young Adult
keywords: Pleth variability index; esophageal Doppler monitoring; fluid responsiveness; hemodynamic monitoring; pulse oximeter; stroke volume