Assessment of Effective Hepatic Blood Flow in Critically Ill Patients by Noninvasive Pulse Dye-Densitometry

Abstact.

Purpose: Effective hepatic blood flow (EHBF) is thought to reflect splanchnic perfusion and the metabolic state of the liver. This study was conducted to examine the relationship between cardiac output (CO) and EHBF using pulse dye-densitometry (PDD) in nonseptic and septic patients, and to assess the prognostic value of this relationship.

Methods: The subjects were 33 critically ill patients, 16 of whom met the criteria for sepsis. Indocyanine green (ICG) was given via a central venous catheter to each patient. CO (l/min) and EHBF (l/min) were assessed with PDD.

Results: CO and EHBF were significantly correlated in the nonseptic patients (r = 0.92, P < 0.001), but not in the septic patients (r = 0.38, P = 0.15). The ratio of EHBF to CO (EHBF/CO) in the septic patients was significantly lower than that in the nonseptic patients (0.08 ± 0.04 vs 0.22 ± 0.05; P < 0.001). Moreover, in the septic patients, the EHBF/CO ratios of nonsurvivors were significantly lower than those of survivors (0.06 ± 0.04 vs 010 ± 0.02; P < 0.01).

Conclusions: In nonseptic patients, the EHBF decreased in relation to the CO. However, the EHBF/CO ratio of septic patients was lower than that of nonseptic patients, suggesting that inadequate splanchnic perfusion or metabolic change occurs in septic patients. Furthermore, the lower EHBF/CO ratio was related with a fatal outcome in septic patients. PDD could be a clinically useful method of assessing splanchnic conditions in critically ill patients.