ClearSight NextGen1 Study

Inclusion Criteria: 1. Signed informed consent 2. Age ≥ 18 years 3. Planned or existing monitoring with an arterial catheter as part of standard of care 4. Patient scheduled to undergo surgery with general anesthesia lasting \> 2 hours Exclusion Criteria: 1. Any significant disfigurement or prior injury to a participant's finger that is intended to be used for monitoring with the study finger cuffs 2. Known left-right difference in blood pressure 3. Extreme contraction of the smooth muscles in the arteries and arterioles of the lower arm and hand, such as may be present in patients with Raynaud's disease 4. Patients deemed not suitable for the study at the discretion of the Investigator 5. Participation in another study that clinically interferes with the current study 6. Treatment with an intra-aortic balloon pump 7. Pregnancy 8. Cardiac surgery including bypass period