Video-angiography in Cerebrovascular Surgery
IC Green (Indocyanine Green ) video-angiography is a new technique of blood-flow measurement that is being used in neurosurgery. The dye is administered intravenously and used in combination with a special microscope to obtain high-resolution, high-contrast video images during micro-neurovascular surgery.
Used in the OR at MMC by neurosurgery
* The OR will order on a patient specific basis. To view order form for printing click here.
* Send one vial and one amp of diluent to the OR as requested. It is stored in the Carousel. Each box contains 6 vials of IC green and 6 amps of diluent.
- -Only the aqueous solvent provided should be used for reconstitution. It is specially prepared sterile water for injection. There have been reports of incompatibility with some commercially available sterile water for injection products.
- -The vial of IC Green should be
reconstituted with the entire contents of the supplied diluent.
Solution must be used within 6 hrs of reconstitution.
- -Normal dose is one vial of reconstituted IC Green, 25mg, administered via IV push
- -Flush lines with NS after administration
- -**Anaphylactic reactions have occurred. Use in caution in patients with an allergy to iodine**.
- -Unknown effects in pregnancy. Use only when clearly indicated.
Indocyanine green will
transiently lower SpO2 readings on a pulse oximeter (Reference, Below)
If persistent or otherwise unexplained, confirm with Arterial Blood Gas
J Clin Monit. 1987 Oct;3(4):249-56.
Methylene blue and indocyanine green artifactually lower pulse oximetry readings of oxygen saturation. Studies in dogs.
Sidi A, Paulus DA, Rush W, Gravenstein N, Davis RF.
Department of Anesthesiology, College of Medicine, University of Florida, Gainesville 32610-0254.
The effects of fluorescein, methylene blue, and indocyanine green on hemodynamic variables and on pulse oximetry and co-oximetry measurements of arterial hemoglobin oxygen saturation (SaO2) and oxyhemoglobin percentage (% HbO2) were evaluated in 16 anesthetized dogs in vitro by co-oximetry (% HbO2) and in vivo by pulse oximetry (SaO2). The light absorbance (optical density) in plasma (range 500 to 800 nm) was measured by a spectrophotometer. Fluorescein did not affect oximetry measurements, plasma light absorbance in the range measured, or hemodynamic variables. Methylene blue caused dose-dependent decreases in measurements made with both forms of oximetry for up to 30 minutes, the decrease being greater and longer lasting with pulse oximetry (P less than 0.05).
Hemodynamic measurements in 5 dogs showed that methylene blue (1 to 5 mg/kg) increased arterial pressure transiently, after which cardiac output, stroke index, and left ventricular stroke work index decreased and left ventricular end-diastolic pressure and systemic and pulmonary vascular resistances increased (P less than 0.05 with 5 mg/kg). Methemoglobin concentration measured by co-oximetry increased significantly (to 19.9 +/- 1.4%, P less than 0.05) 1 minute after 5 mg/kg of methylene blue was injected. Methylene blue had a dose- and time-dependent effect on plasma light absorbance, and this effect peaked in the 660- to 670-nm range. The data do not distinguish the relative contributions of physiology (hemodynamic change), chemistry (methemoglobin production), and physics (optical properties) to the decrease in pulse oximetry and co-oximetry measurements that follows injection of methylene blue. Indocyanine green affected neither hemodynamic variables nor co-oximetry readings but decreased pulse oximetry readings for up to 10 minutes dose dependently.