title: Pulse dye densitometry and indocyanine green plasma disappearance in ASA physical status I-II patients.
abstract: BACKGROUND
  Indocyanine green plasma disappearance rate (ICG-PDR) is used to evaluate hepatic function. Although hepatic failure is generally said to occur with an ICG-PDR <18%/min, ICG disappearance rate is poorly defined in the healthy population, and a clear cutoff value of ICG-PDR that discriminates between normal hepatic function and hepatic failure has not yet been described. We therefore defined the ICG disappearance rate in an otherwise healthy patient population. In addition, we evaluated the noninvasive measurement of ICG-PDR (transcutaneously by pulse dye densitometry [PDD] at the finger and the nose) and compared these with the simultaneously performed invasive measurements of ICG-PDR (in arterial blood).
  
  
  METHODS
  In patients without signs of liver disease, scheduled for elective nonhepatic surgery, 10 mg ICG was administered IV and ICG-PDR measured by PDD (DDG-2001, Nihon Kohden, Tokyo, Japan). In a subset of patients, arterial blood samples were gathered to compare PDD with invasive ICG measurements. Methods were compared using Bland-Altman analysis. The results of our study and reported studies on discriminative use of ICG-PDR in assessing liver failure were used to construct receiver operating characteristic curves.
  
  
  RESULTS
  Forty-one patients were studied: 33 using the finger probe and 8 using the nose probe. The mean +/- SD noninvasive ICG-PDR in this patient population is 23.1% +/- 7.9%/min (n = 41) with a range of 9.7% to 43.2%/min. Bias (+/-2 sd, limits of agreement) for ICG-PDR measured by PDD compared with those measured in arterial blood were 1.6%/min (-5.2% to 8.3%/min) for the finger probe and -6.0%/min (-15.5% to 3.4%/min) for the nose probe.
  
  
  CONCLUSIONS
  ICG-PDR values in a population without liver failure ranged well below 18%/min, cited as the cutoff value for hepatic failure. This cutoff value needs reconsideration. In addition, we conclude that the ICG concentration is adequately determined noninvasively by PDD.
authors.affiliation: Department of Anesthesiology, Leiden University Medical Centre, Leiden, The Netherlands. m.reekers@lumc.n
authors.forename: Marije
authors.initials: M
authors.lastname: Reekers
authors.forename: Mischa J G
authors.initials: MJ
authors.lastname: Simon
authors.forename: Fred
authors.initials: F
authors.lastname: Boer
authors.forename: René A G
authors.initials: RA
authors.lastname: Mooren
authors.forename: Jack W
authors.initials: JW
authors.lastname: van Kleef
authors.forename: Albert
authors.initials: A
authors.lastname: Dahan
authors.forename: Jaap
authors.initials: J
authors.lastname: Vuyk
mesh_terms: D000328:Adult; D004396:Coloring Agents / Q000493:pharmacokinetics; D003720:Densitometry / Q000379:methods; D005260:Female; D006304:Health Status; D006801:Humans; D007208:Indocyanine Green / Q000493:pharmacokinetics; D008111:Liver Function Tests; D008297:Male; D008875:Middle Aged; D013053:Spectrophotometry
chemical_list: D004396:Coloring Agents; D007208:Indocyanine Green