THE DOCTOR'S BAG
the blog about the medicine and surgery of yesteryear
Dr Keith Souter aka Clay More
"My chest sounds just like an old barrel, Doc." Then he asked me why doctors always tapped on his chest before they listened with their stethoscope. So I told him that it was to get an idea of the state of the inner organs. He was delighted when I told him that he had actually been correct when he used the barrel analogy, because it was from tapping wine casks that the technique was devised. Or so the story goes.
The Doctrine of Humors
Until the discoveries of anatomy and the early experiments on physiology, medicine was essentially a philosophical process. The dominant principle in medicine was called the Doctrine of Humors. This was an ancient Greek theory that postulated the existence of four fundamental humors or body fluids (from the Latin umor or humor, meaning ‘moisture’ or ‘fluid’) which determined the state of health of an individual. These humors were blood, yellow and black bile and phlegm. Doctors tried to work out which humor was in excess or deficiency and treatments were aimed at removing the illness producing humor by bleeding, purgation and the use of emetics.
Although the doctrine of hummers was based on these so-called fluids, doctors had no way of determining whether there actually was excess fluid in the body.
Tapping the body
When anatomy and physiology started to give doctors an idea of what really happened in the body, there was a need to be able to work out the state of the internal organs. Towards the end of the eighteenth century an Austrian physician, Dr Leopold von Auenbrugger, made the breakthrough when he invented the simple technique of percussion. This is the technique that doctors still use during their examination of the chest and abdomen.
Dr Leopold von Auenbrugger (1722-1809)
Leopold von Auenbrugger’s father was a hotel owner. It is thought that the method used to check on the level of wine in casks, by tapping on them to determine where the level of wine was, was something that he had seen in his father’s cellar throughout his childhood. His genius was in adapting it to the human body.
Von Auenbrugger spent ten years examining thousands of patients, and correlating post-mortem findings in order to build up a whole science of percussion. His book, Inventum Novum, translated into English as ‘A New Discovery that Enables the Physician from the Percussion of the Human Thorax to Detect the Diseases Hidden Within the Chest,’ is now considered one of the most important classics of medicine.
Invntum Novum - one of the classics of medicine
Pleximeter and hammer
Doctors began using little gadgets called pleximeters, which they placed o the part of the body to be percussed. Then they would tap it with a percussion hammer. These became more and more ornate and something of a status symbol. No self-respecting physician would be without his pleximeter in waistcoat pocket.
The Stethoscope gradually takes over
The stethoscope as invented by Rene Laennec, a Parisian physician in 1816, was a monaural device. That is, it was a simple stiff tube with an earpiece at one end and a collecting horn at the other. It was essentially the same as the ear trumpet used by the hard of hearing. The binaural, flexible tubed stethoscope as perfected and designed by Dr George Cammann in 1852 did not become commonly used until after the Civil War. Few Civil War doctors would have a use for one, they would have fallen back on the technique of percussion.
Dr George Cammann's stethoscope, which revolutionised medicine
Indeed, the esteemed Harvard medical school did not even possess one until 1868!
All doctors still us it
Percussion is taught to all medical students and it is of incredible value when there is just you and th patient, no x-rays or scans.
The technique involves laying one hand flat on the part of the body to be examined, usually the chest or the abdomen. The middle finger of one hand then taps the middle finger of the flattened hand in order to produce a noise. Four types of noise can thus be elicited, allowing the examiner to determine the state of certain organs. Essentially, the amount of dullness or hollowness can give a lot of information, and it can help in determining whether or not fluid is present, whether an organ is enlarged, or whether there is an excess of air.
Going back to my cheerful patient, he had dullness to percussion at the base of one lung, indicative of his pneumonia, which was backed up by the stethoscope a few moments later.
Dr George Goodfellow
Dr George Goodfellow would have used the technique every day in assessing people's chests or abdomens. And if it was good enough for him, it's good enough for the rest of us.