Determination of plasma volume by indocyanine green – validation of the method and use in patients after cardiopulmonary bypass

Abstract

PV determination by peripheral i. v. injection of ICG produced reliable and consistent results when a reactive hyperaemia was produced by a tourniquet prior to injection. Therefore, central venous injection of ICG may not be prerequisite for precise measurements of PV. The expected acute increase in PV after infusion of commonly used plasma expanders after cardiac surgery was not found.

Technical and physiological background of plasma volume measurement with indocyanine green: a clarification of misunderstandings

“…Menth-Meier et al (28) demonstrated that it is appropriate to perform peripheral dye injection for PV measurement by ICG-DT. However, others advised induction of hyperemia before dye injection to accelerate recirculation (14,28).…”

“…Menth-Meier et al (28) demonstrated that it is appropriate to perform peripheral dye injection for PV measurement by ICG-DT. However, others advised induction of hyperemia before dye injection to accelerate recirculation (14,28). Additionally, in preliminary, unpublished experiments (n ϭ 10), we established that injection into one peripheral catheter and withdrawal of the timed samples from this and, simultaneously, an additional catheter on the other arm led to the same PV:…”

“…Because ICG rapidly binds to plasma proteins, validation of its distribution space using the distribution space of these proteins is justified. Validation with the reference method, radioiodinated albumin, was performed in 10 healthy volunteers and 21 patients after elective open-heart surgery, with excellent results even for peripheral ICG injection (28). In vitro and in vivo validation was performed by another group; however, they used a questionable reference tracer (radiochromium-labeled red blood cells) (5).…”

“…In addition, several studies revealed a possible mutagenic potential for Evans blue (25,31). In 1968, indocyanine green (ICG) (3), a relatively unstable dye with an initial distribution volume comparable to that of Evans blue (16) and labeled albumin (28), was used for the first time to determine "blood volume." Further clinical applications are measurement of cardiac output (10) and liver function (6).…”

Impact of the time window on plasma volume measurement with indocyanine green

“…Indocyanine green (ICG), besides monitoring hepatosplanchnic blood flow (Sakka et al 2007, Stehr et al 2005, has been frequently used for PV measurements (Belin de Chantemèle et al 2006, Bradley and Barr 1968, Haller et al 1992, Jacob et al 2003, Rehm et al 1998, 2000a, 2000b). Although PV is intra-individually inconstant, validation of this method has been performed successfully (Haneda and Horiuchi 1986, Jacob et al 2007, Menth-Meier et al 2001. Repeatability of the ICG-dilution technique (ICG-DT) has been shown to be excellent (Haller et al 1993, Rehm et al 1998 as has the accuracy (Menth-Meier et al 2001), provided circulatory steady-state conditions are maintained between two corresponding measurements (Jacob et al 2007).…”