Overestimation of indocyanine green-derived plasma volume can occur in the presence of generalized capillary protein leakage. This overestimation was examined early after cardiac surgery by using the simultaneous measurement of the initial distribution volume of glucose. We suggest that overestimation of the traditional dye dilution method is negligible, but apparent over- or underestimation of pulse dye densitometry-derived plasma volume cannot be negligible.

Using TEE, we could evaluate daily changes of the area of density in the dependent lung region in the intensive care situation. The areas of density in ARDS patients changed from day to day following the changes of oxygenation.

No abstract

Objective: Our experimental studies have indicated that the initial distribution volume of glucose (IDVG) has potential to evaluate the central extracellular fluid (ECF) volume status in the body. The purpose of the present study was to compare the IDVG and cardiac output (CO) in critically ill patients with or without expansion of the central ECF volume and to test whether a larger IDVG is observed during the presence of increased central ECF volume than during the absence of it. Design and Setting: The study was prospective and was conducted in the intensive care unit, University of Hirosaki Hospital, after approval of the institutional ethical committee. Patients: Fourteen patients with accumulation of the central ECF volume (the accumulation group) and 29 patients without it (the non-accumulation group) were studied. Interventions: Glucose 5 g was infused over 30 s when the patients’ hemodynamic states were relatively stable. Blood samples were taken immediately before infusion and during 7 min post-infusion. Thermodilution CO was also measured before each glucose challenge. A total of 81 comparisons were performed. Measurements and Results: The IDVG was calculated using a one-compartment model. A linear correlation was obtained between the IDVG and CO in the non-accumulation group (r = 0.89, n = 54, p < 0.001). The IDVG-CO ratio was higher in the accumulation group than in the non-accumulation group (p < 0.01). The increased plasma glucose concentrations at 3 min postinfusion were inversely proportional to the IDVG (r = -0.90, n = 81, p < 0.001). Conclusions: Results demonstrated that a larger IDVG was obtained during accumulation of the central ECF volume and support the hypothesis that the IDVG reflects the central ECF status in critically ill patients characterized in our study, even though CO influences the IDVG.

This study was designed to determine whether endotoxin-induced generalized capillary protein leakage can be detected using the ratio of indocyanine green (ICG) and glucose dilutions. Plasma volume determined by the ICG dilution method (Vd-ICG) and the initial distribution volume of glucose (IDVG) were assessed simultaneously before and after either the administration of lipopolysaccharide (LPS) 0.3 mg kg-1 or equal amounts of isotonic saline in two groups of eight dogs, using a one-compartment model after simultaneous infusions of both ICG 0.5 mg kg-1 and glucose 100 mg kg-1. The IDVG has been shown to indicate the extracellular fluid volume of highly perfused organs including plasma. All post-treatment values decreased compared with the pre-treatment values (P < 0.05), except Vd-ICG in the LPS group, even though the post-treatment total plasma protein concentration of the LPS group decreased significantly compared with the pre-treatment value (P < 0.05). The post-treatment Vd-ICG/IDVG ratio of the saline group remained unchanged compared with that of the pre-treatment, and the post-treatment ratio of the LPS group increased significantly (P < 0.01). It can be concluded that overestimation of the Vd-ICG can occur after endotoxin injection, which can be detected by simultaneous measurements of the Vd-ICG and the IDVG.