There are certain pieces of medical equipment that are seen as so vital to healthcare professionals that nearly everyone in the country has been treated with one at some point.
One of these is the sphygmomanometer, more commonly known as the blood pressure gauge.
It consists of a cuff attached to a dial with an inflatable pump or digital monitor that actively tests blood pressure when wrapped around the upper arm.
Everyone has used one at some point in their lives, and some people diagnosed with high blood pressure or are seen as having a heart risk may be provided with an at-home kit that is designed to be easier to use, at the expense of being slightly less accurate than a properly calibrated and used manual kit.
The original sphygmomanometer was first used in 1881 by the personal doctor of the emperor of Mexico, Samuel Siegfried Karl Ritter von Basch.
Its design was very similar in concept to those used today, featuring a rubber bulb that was filled with water (rather than air) that restricted arterial blood flow and was itself connected to a mercury column that registered blood pressure.
It was not a perfect solution, but even at the time, it was criticised by some doctors for being “too high tech” as compared to manually checking the pulse with fingers in order to make a diagnosis.
By 1896, it was paired with an inflatable cuff by Scipione Riva Rocci, which made it far easier to use and thus more widely usable within the medical world.
This design was, in turn, revised by neurosurgeon Harvey Cushing, a pioneering innovator who was the first to diagnose brain tumours using X-rays and developed neurosurgical techniques that dramatically increased the survival rate of brain tumour surgery.
The final refinement came in 1905 when Nikolai Korotkoff developed a sphygmomanometer that could read both systolic and diastolic blood pressure.