NIRS provides a noninvasive measure of local tissue perfusion that can be used during non-pulsatile flow conditions such as cardiopulmonary bypass (CPB) or cardiac arrest. In recent randomized trials, cerebral oximetry monitoring has been associated with shorter recovery room and hospital stay in non-cardiac surgery and with a decrease in major organ dysfunction and in intensive care length of stay after cardiac surgery, thus providing rationale for its use.
Cerebral Oximetry Setup:
- Ensure proper device-specific pad placement.
- The skin should be cleaned with an alcohol wipe before placing the pads. This skin must be dry or the pads will not stick. Avoid placing sensors on hair.
- The pads should be placed over the frontal eminences transilluminates cortical brain areas corresponding to the junction between the anterior and middle cerebral artery.
- Follow device-specific protocol to establish baseline values. The baseline should be established prior to induction and prior to O2 delivery via facemask.
- Adjust head position.
- Rule out mechanical obstruction.
- Check cannula placement.
- Check for superior vena cava (SVC) obstruction and adequate venous drainage.
- Increase mean arterial pressure (MAP).
- Verify systemic oxygenation.
- Increase pump flow rate.
- Normalize PaCO2.
- If Hgb < 7 gm/dL, consider RBC transfusion (one unit at a time).
- Check for aortic dissection.
- Avoid cerebral hyperthermia during rewarming.
- Ensure appropriate depth of anesthesia.