Spinal metastases account for 60% of all malignant bone metastases and represent a medically important treatment goal. For patients with malignant tumors diagnosed at this stage, performing En bloc spondylectomy with wide margin of resection facilitate the improvement in quality of life including ambulatory ability, daily activities independence and attenuation of bone pain. However, En bloc spondylectomy is a major operation with long operation time and frequent hemodynamic instability during the operation. Therefore, the anesthetic care plays an important role and an enhanced recovery after surgery (ERAS) is the goal.

For the ERAS anesthesia protocol for En bloc spondylectomy, we propose two major components to achieve this goal: (1) an encephalographic spectrum guided multimodal anesthesia combined with ultrasound-guided nerve block and (2) the advanced machine-learning algorithm index, namely the hypotension predictive index (HPI) guided hemodynamic protocol.

The anesthetic protocol comprises of two major proposed components to enhanced recovery after spine cancer total en bloc resection. First, a multimodal general anesthesia consisting of GABAnergic hypnotic agent (propofol or sevoflurane), ketamine and dexmedetomidine was conducted by using the encephalographic density spectrum array. In addition, ultrasound-guided erector spinae plane block is applied. These techniques potentially prevent anesthesia induced delirium and may profoundly improve postoperative analgesic quality. Second, advanced hemodynamic monitoring device, namely the hypotensio predictive index, will be used for prevention of intraoperative hypotension and facilitate precise transfusion protocol.

Inclusion Criteria:

• Patients undergoing metastatic spine cancer resection surgery

Exclusion Criteria:

• Expected survival less than 6 months
• Previous surgery or radiotherapy for the spine metastasis