Disclosed herein are methods, systems and devices to monitor vascular volume status utilizing at least one oximetry/photoplethysmography sensor. The methods, systems and devices provide an alternative to conventional vascular volume monitoring methods while enabling reliable, non-invasive, and automatic monitoring of vascular volume to avert patient hypotension. The methods, systems and devices may be employed in the context of both inpatient and outpatient facilities and may also be incorporated into conventional monitoring devices, techniques and equipment.
