Near-infrared spectroscopy (NIRS) is a novel method for the measurement of
tissue oxygenation and may have a role in monitoring liver oxygenation and
viability, The aim of this study is to validate the application of NIRS for
monitoring hepatic tissue oxygenation. Large Landrace pigs (n = 12) underw
ent laparotomy and liver exposure, Total hepatic blood flow (THBF) was meas
ured by the Transonic Medical Flowmeter system. NIRS probes were placed on
the liver surface to continuously record changes in hepatic tissue oxyhemog
lobin (HbO(2)), deoxyhemoglobin (Hb), and the reduction-oxidation state of
cytochrome oxidase (Cyt Ox). Reduction of hepatic tissue oxygenation was ac
hieved by hepatic vascular inflow occlusion (n = 6) or reduction of inspire
d oxygen (FIO2; n = 6), The THBF changes correlated significantly with hepa
tic HbO(2) (r = 0.84; P < .001) and Cyt Ox (r = 0.88; P < .001), With reduc
tion of FIO2, a significant correlation was found between arterial oxygen s
aturation and hepatic HbO(2) and Hb (r = 0.99 and r = -0,99, respectively;
P < .0001), NIRS measurement of liver parenchymal oxygenation correlates we
ll with changes in liver blood flow and arterial oxygenation, Copyright (C)
1999 by the American Association for the Study of Liver Diseases.