Tissue Oxygenation of the Tibial Anterior Muscle After Clamping of the Femoral Artery

Influence of Sevoflurane Preconditioning on Tissue Oxygenation of the Tibial Anterior Muscle Measured by Near-infrared Spectroscopy After Clamping of the Femoral Artery for Vascular Surgery

Ischemic preconditioning is defined as protection from cell damage induced by prolonged ischemia by preceding cycles of short ischemia. Hence, ischemic preconditioning could reduce ischemic lesion during clamping a femoral artery for vascular surgery. In this prospective, randomized pilot study is investigated if clamping of the femoral artery leads to ischemia of the calf measurable by near-infrared spectroscopy. In addition to this, the effect of sevoflurane preconditioning on ischemia of the calf is measured.

Ischemic preconditioning is performed by clamping of the femoral artery for five minutes in 40 patients. In 20 patients sevoflurane preconditioning is performed five minutes before ischemic preconditioning by inducing sevoflurane anesthesia for five minutes. Muscle tissue oxygenation is measured bilaterally in the anterior tibial muscle by near-infrared spectroscopy (INVOS, SOMANETICS, Troy, Michigan/ USA) during preconditioning and following ischemia.Clinically relevant ischemia was defined as a decrease of tissue oxygen saturation to 95 % of baseline.

Inclusion Criteria:vascular surgery with clamping of a femoral artery. -

Exclusion Criteria:

-