Orthogonal polarization spectral imaging of the microcirculation during acute hypervolemic hemodilution and epidural lidocaine injection

We used Orthogonal Polarization Spectral Imaging to examine the microcirculation of the vaginal mucosa in nine anesthetized patients during two consecutive anesthetic interventions: hypervolemic hemodilution using hydroxyethyl starch followed by thoracic epidural lidocaine. Images taken before and after each intervention were compared. During hypervolemic hemodilution, systolic blood pressures increased significantly, but functional capillary density remained unchanged. Epidural anesthesia decreased systolic and diastolic blood pressures, but there was no change in capillary density, venular diameter, or flow velocity. We concluded that when using Orthogonal Polarization Spectral imaging, no consistent effects on the microcirculation of the vaginal wall can be detected