Hypotension Prediction Index (HPI) SMART-BP Trial

Inclusion Criteria: 1. Signed informed consent 2. Age \>18 years 3. ASA Physical Status \> 2 4. Noncardiac surgery with expected surgery duration \> 2 hours (example include: orthopedic, spine, urology, and general surgery) 5. Planned blood pressure monitoring with an arterial line catheter; 6. General anesthesia; Exclusion Criteria: 1. Participating in another interventional Trial; 2. Contraindication to arterial blood pressure monitoring; 3. Subjects with a physical site area too limited for proper Sensor placement 4. Serum creatine \> 175 μmol/L (\>2.0 mg/dL) or CKD stage \> 3A 5. Scheduled for intracranial surgery with permissive hypotension; 6. Patient who is confirmed to be pregnant and/or nursing mothers; 7. Patients with an intra-aortic balloon pump (IABP) or ventricular assist device(s); 8. Have a condition that precludes routine or tight blood pressure management such as surgeon request for relative hypotension; 9. Emergency surgery; 10. Require beach-chair positioning; 11. Scheduled for cardiac surgeries 12. Have previously participated in the SMART-BP trial.