Observations on M. Laennec's method of forming a diagnosis of the diseases of the chest by means of the stethoscope, and of percussion; and upon some points of the French practice of medicine

by Charles Scudamore

It has been said that the use of the stethoscope may be injurious, by leading the physician to know too much of the danger in a bad case; to make him despond and resign the patient to his fate too soon. Such an observation scarcely requires refutation. In no instance of dangerous disease can the physician see his way too clearly; and at all times to know the disease, is at least making a considerable approach towards the cure. The judgment, the discretion, and the humanity of the good physician, will be a sure protection to the patient against any abrupt decision, any gloomy opinion, and much more against unkind desertion, in the most hopeless circumstances of disease.

The following case serves to shew the converse proposition, and the happy purpose to which superior knowledge and discernment were applied.

M. Laennec was consulted in the case of a gentleman who was supposed to be dying from phthisis pulmonalis, and in a state so desperate, that he was not expected by his medical attendant to survive more than two or three days.

M. Laennec made his usual investigation, and persuaded himself that the case had been mistaken, and that the alarming symptoms did not arise from ulceration of the lungs, but from empyema, or purulent collection within the pleuræ. He strongly recommended that the operation for this disease should be performed; and, after a little hesitation and delay, his advice was adopted. A large quantity of pus was evacuated, and immediate relief was afforded. The amendment was rapid, and the progress of cure so favourable, that the gentleman recovered his health in less than three months.

In thus rendering my homage to the merits and science of M. Laennec, I do not wish it to be thought, that I consider even his authority as infallible; but it is nothing more than is justly due to the new practice, to admit, that it may become of very great importance; and, that by no other mode can we examine the interior state of the chest, with equal accuracy.

Let it be further remarked, that we are not required to lay aside any of our ordinary methods of investigation: This additional mode comes to our aid in cases of obscurity and difficulty. If the physician of long experience be so confident in his powers of diagnosis, that he rejects this invention as unnecessary for his purpose, it need not follow that he should disapprove of it for others who are less experienced, and are more diffident of their skill and penetration. Most assuredly it is a great help to the judgment; and I am fully persuaded, that, in proportion as it is understood, it will be more generally received, and more highly esteemed.

If the naked ear be applied to any part of the chest, it is made sensible of the entrance of the air into the cells of the lungs; and the beginner in this study will receive the impression more fully and sensibly, than by the medium of the stethoscope, because the vibrations are collected from a larger surface; but it is a less accurate method, and much less analytical. He may with advantage practise with the naked ear occasionally, in order to become familiar with the sounds of respiration; but under many circumstances, such a mode is inconvenient and inapplicable. The listening by the ear only is technically called, immediate auscultation; and by the stethoscope, mediate auscultation.

In examining the chest of a person whose respiration is calm, we should desire that it be made purposely quicker, and stronger; but not so audibly as to cause confusion by that external sound. The perception afforded to the auscultator by healthy lungs, is that of air entering a cavity, as it were with a gentle stream of sound. If the pupil first apply his naked ear to the chest, he will have a clear idea of what he has to expect. As a general rule, in making our investigation of the state of the lungs, the stethoscope should be applied immediately under the clavicle, near the axilla; and the learner will do well to choose the right side, lest he become confused by the action of the heart. In seeking for ordinary respiration, it should not be applied near the trachea, as the stronger action of the air in the bronchial tubes would mislead the ear. To ascertain the state of the posterior part of the lungs, the instrument is to be applied on the scapula, above or below the spinous process.

In my own practice, I have derived the utmost advantage from the use of the stethoscope in cases of pneumonia, with regard to local treatment. When we find a patient ill with severe symptoms arising from inflammation of the lungs, we do not require the aid of auscultation to determine us in employing the lancet as our first and most important remedy; but we may desire immediately to join with the general bleeding, local depletion; and, most commonly, the period arrives when we wish to use local treatment exclusively, by cupping or leeches, and blisters. Under such circumstances, it is of the utmost importance that we should be able to ascertain the exact seat of the inflammation; and when, as commonly happens in pneumonia, the patient cannot direct us by any sensation of pain, but is labouring under a general sense of oppression and suffocation; we resort to the stethoscope as a positive and most valuable source of instruction. Even when it is manifested to us by ordinary indications, that the inflammatory action is prevailing on one side of the chest, it is of great advantage that we can detect, by means of the instrument, the particular part of the lungs most affected. I shall illustrate the truth of these remarks by the recital of a few cases.

A gentleman dangerously ill with inflammation of the lungs, which had supervened on an attack of asthma, experienced, in the evening, a renewal of the feelings of suffocation, which, in the morning had been relieved by copious bleeding from the arm. In the middle of the upper part of the chest, he had a severe sensation of tightness, but was not conscious that the lungs were affected more on one side than the other. His cough was most urgent. The stethoscope, applied to the lower part of the right side, conveyed to the ear a strong sonorous rattle, both on inspiration and expiration, much resembling the sounds of loud snoring. These sounds could not be detected in any other part of the chest. In addition, therefore, to a fresh bleeding from the arm, cupping was used very freely at this part, and with evident good effect. Almost immediately the sounds abated. Two days after, leeches and a large blister were used with further benefit; and the actual relief of the patient perfectly corresponded with the improving indications afforded by the stethoscope. Occasional bleedings from the arm were afterwards required; but the inflammation was finally subdued, and the constitution was restored to its previous state; this gentleman being habitually subject to spasmodic asthma.