The routine intra-operative use of pulse oximetry for monitoring can prevent severe thromboembolic complications in anterior surgery.

AbstractIntroduction Anterior access to the lumbar spine isestablished for disc replacement surgery and anteriorinterbody fusion in the lumbar spine. The spine is accessednormally from the left side either by a transperitoneal orretroperitoneal approach through a midline or oblique skinincision. After reaching the retroperitoneum and dependingon the level of exposure, the surgeon has to mobilise andretract the aorta or left common iliac artery, as well as theleft common iliac vein or internal vena cava to the rightlateral border to address the whole disc space. The leftcommon iliac artery is especially stretched during inter-vertebral disc exposure putting it at a greater risk ofadverse events. Not surprisingly, vascular adverse eventslike direct injuries, thrombosis and embolism are fearedcomplications in anterior surgery. Permanent intra-opera-tive left leg oxygen saturation surveillance via pulseoximetry can help detecting embolic situations therebyallowing immediate treatment minimising the leg ischemiaor preventing limb loss.Case report In the presented case, a 61-year-old malepatient undergoing a two-level anterior interbody fusionlost oxygen saturation in the left leg after vessel retractionfor exposure. After cage insertion and release of theretractor blades, the pulse oximetry signal did not returnand no pulses were found during instant Doppler investi-gation below the femoral artery, indicating severe embo-lism in the left leg. The left common iliac artery wasclamped and opened showing a ruptured calcified plaquewith adherent fresh thrombotic material. An endovascularembolectomy in the superficial and deep femoral arteryrevealed several small thrombi. An artherectomy of thecommon iliac artery followed by patch closure was per-formed. Immediately after clamp release, pulse oximetryreturned and Doppler signals were detectable at the tibialisposterior and dorsalis pedis artery. Post-operative recoverywas uneventful and pulses were palpable at all times.Conclusion Arterial adverse events in anterior accesssurgery are rare complications but none the less, it is ofparamount importance to detect and treat these situationsimmediately. This case highlights the need of routine pulse