Having your blood pressure measured via an inflatable arm cuff can be stressful, potentially causing that pressure to be higher than normal when the reading is taken. A new finger clip device, however, is promised to make the process quicker and easier for patients.
Presently being developed at the University of Missouri, the prototype tool looks much like the finger-applied oximeters that are currently used to read patients’ blood oxygen levels.
And just like an oximeter, it shines light through the skin, analyzing the light which is reflected back by the blood within the finger.
The new device does so at two points along the length of the finger, however, using two photoplethysmography (PPG) sensors.
By measuring the millisecond lag between the times at which each pulse of blood is detected by each sensor, it’s possible for a linked computer to calculate the patient’s pulse wave velocity – in other words, the speed at which the blood is travelling through their bloodstream.