EFFECTS OF EPHEDRINE ON INDOCYANINE GREEN CLEARANCE DURING SPINAL-ANESTHESIA - EVALUATION BY THE FINGER PIECE METHOD

We measured indocyanine green (ICG) clearance in 20 patients scheduled for elective surgery during spinal anesthesia to determine whether ep hedrine affects the hepatic circulation during spinal anesthesia. The clearance was measured by a new noninvasive finger piece method. We fo und that a decrease in arterial blood pressure secondary to spinal ane sthesia significantly reduced ICG, whereas there were no significant c hanges in ICG clearance in the patients whose arterial blood pressures were maintained at preanesthetic levels by ephedrine. Other hemodynam ic variables, heart rate, cardiac index, and stroke volume index, did not change significantly in either group. We conclude that hepatic blo od flow is decreased by hypotension due to spinal anesthesia and can b e attenuated by ephedrine administration.