Wednesday, November 30, 2005

Sphygmomanometer

I was thinking about blood pressure. Who in the world figured that out? How did someone stumble across the procedure that involves an air-filled cuff around the upper arm with a stethoscope listening for beats? What were they looking for? Perhaps my friend Dr. Jones can ask his wife, Dr. Jones, about it.

It is amazing to think about all the discoveries that have been made and all there is to know.  I would imagine that many medical discoveries were accidents. But along the road of experimentation, the wonder of God’s creation of the human body becomes even more impressive to the thinking mind. What a great God we serve, who never had to figure out anything about the human body. He knows it precisely and exhaustively. We humans just have to figure it out along the way.

Of course, sphygmomanometer had to be an accident. No one could come up with a word like that on purpose. But I am glad it works.

2 comments:

Brian Jones said...

I will try to remember to ask the other Dr. Jones about this.

I was thinking about it, too, recently because: (a) I had mine checked when I went to see the doctor recently and (b) I know some guys who suffered strokes this year, one fatally.

Brian Jones said...

From Wikipedia, the free encyclopedia: http://en.wikipedia.org/wiki/Nikolai_Korotkoff

Nikolai Sergeievich Korotkov (also Korotkoff) (February 13, 1874–1920) was a pioneer of 20th century vascular surgery and developed a technique for measuring blood pressure in 1905. He was physician-in-chief of the Metchnikov Hospital in Leningrad until his death in 1920.

Here is his report to the Imperial Military Academy in St. Petersburg in 1905:
The cuff of Riva-Rocci is placed on the middle third of the upper arm; the pressure within the cuff is quickly raised up to complete cessation of circulation below the cuff. Then, letting the mercury of the manometer fall one listens to the artery just below the cuff with a children's stethoscope. At first no sounds are heard. With the falling of the mercury in the manometer down to a certain height, the first short tones appear; their appearance indicates the passage of part of the pulse wave under the cuff. It follows that the manometric figure at which the first tone appears corresponds to the maximal pressure. With the further fall of the mercury in the manometer one hears the systolic compression murmurs, which pass again into tones (second). Finally, all sounds disappear. The time of the cessation of sounds indicates the free passage of the pulse wave; in other words at the moment of the disappearance of the sounds the minimal blood pressure within the artery predominates over the pressure in the cuff. It follows that the manometric figures at this time correspond to the minimal blood pressure.

Also:

From Wikipedia, the free encyclopedia: http://en.wikipedia.org/wiki/Sphygmomanometer


A sphygmomanometer or blood pressure meter is an inflatable cuff used to measure blood pressure. The word comes from the Greek sphygmus (pulse), plus the scientific term manometer (pressure meter). The device was invented by Samuel Siegfried Karl Ritter von Basch. Scipione Riva Rocci, an Italian physician, introduced an easy to handle variation in 1896. Harvey Cushing discovered this device 1901 and popularized it.

A sphygmomanometer usually consists of an inflatable cuff, a measuring unit (the manometer), a tube to connect the two, and (in models that don't inflate automatically) an inflation bulb also connected by a tube to the cuff. The inflation bulb contains a one-way valve to prevent inadvertent leak of pressure while there is an adjustable screw valve for the operator to allow the pressure in the system to drop in a controlled manner.