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most frequently experienced, and errors most readily committed.
It must be acknowledged that for the attainment of familiarity with the practice of auscultation a considerable devotion of time and labour is required; but it will scarcely be disputed that, in addition to the difficulties inherent in the subject, others have arisen : 1st. From attempted refinements, not authorised by existing phenomena. 2nd. From the use of terms, either inaccurate, or not sufficiently distinctive. The first of these mistakes tends to render the art of auscultation unattainable ; the second introduces confusion, which is often worse than ordinary error, because it is a form of error difficult to correct. I do not expect in these introductory remarks altogether to avoid such defects ; but it will be my aim to describe such sounds only as can be readily recognised ; and to select such terms as shall express as marked a difference as possible, between sounds differing in their character and significancy. Whilst avoiding any unnecessary alteration of terms which have been sanctioned by general usage, I shall not scruple to displace those which are obviously inaccurate, or calculated to induce practical error.
In attempting to form systematic classifications of auscultatory phenomena, confusion has often arisen from the circumstance, that some sounds have been designated according to the impression made on the ear, and others in subserviency to some theoretical idea regarding their mode of origin. Thus, for example, the crepitant rhonchus, although from its name implying a sound dry in character, is yet placed by some authors among moist rhonchi, on the supposition of its being due to the presence of secretion. If it be considered expedient to adopt an arrangement founded on the nature of the impression, whether of dryness or of moisture, made on the ear, the crepitant rhonchus should certainly be placed in the first of these divisions : and my own view of its cause would induce me, on theoretical grounds, to consider this its appropriate place. It is difficult by any verbal representation to convey to one man a correct idea of the impressions made on the senses of another; and, in adapting terms to describe impressions on the ear, it is undesirable to introduce those which are expressive of pathological conditions. The remarks of Skoda, that crackling is a dry sound, and indicates the presence of fluid, probably of a tenacious character, in some of the bronchial tubes, or in a cavity, may serve to illustrate the contradictory character of the language, to which designations involving speculative opinions are apt to lead.
In the attempt now made to simplify the subject I shall not include all the auscultatory sounds, but chiefly those of practical importance ; which are most easily confounded in consequence, either of some supposed similarity in their character, or of the ambiguous terms by which they have been described. Percussion sounds, modifications of sound derived from the voice, cardiac, venous and arterial murmurs are omitted ; since they are for the most part easily distinguished, and the terms by which they are designated are sufficiently expressive. It is undesirable to give similarity of name, and juxta-position in arrangement, to sounds perfectly distinguishable, and characteristic of diseases altogether different in
their nature ; as is often done, for example, with respect to the crepitation of inflamed lungs, and the moist crepitation of consumption. With a view to avoid such inconvenient commingling of ideas, and to facilitate the comprehension of the subject in its practical applications, I would venture to propose, as simple, distinct, and suited for clinical purposes, the following division into bubbles, clicking, crepitation, crackling, and vibration.
The first column in the opposite table exhibits the arrangement which I propose; the second, the corresponding terms in most frequent use; the third contains brief descriptions of the distinctive characteristics of each sound; the fourth notes the occurrence of the sound, whether chiefly in inspiration or expiration, or in both; the fifth shows the most common seat of each sound ; and the sixth, the principal disease in which each sound is manifested.
I. BUBBLING SOUNDS are produced by air passing through secretion in the bronchial tubes, as peculiarly occurs in bronchitis; in those of moderate calibre, constituting what has been usually designated mucous rhonchus. The smaller bubbling rhonchus produced in the capillary bronchi, commonly known as subcrepitant, should rather be termed sub-mucous ; if, from respect to long usage, the somewhat questionable term “ mucous” be retained. To these bubbling sounds the term rhonchus is appropriate; but I do not dignify with this title sounds probably produced externally to the cells, such as crackle, and true crepitation ; which are not proved to have any relation to the passage of air through secretion, or along vibrating tubes.
Humid crepitation, 2, 3, or 4 clicks.
dry crackling, sounds.
rhonchus. IV. Crepitation. Crepitant rhon- Numerous minute
chus. similar rapid puffs,
like salt on the fire,
hair between the
II. CLICKING consists of a series of sounds, few in number, exactly corresponding to the term, audible in some degree during expiration as well as inspiration, and probably never existing except when softened tubercle is present.
III. CRACKLING, a term which itself defines the sound, consists of a few (not more than three or four) crackles, limited to the period of inspiration, seeming to arise at a distance from the ear, probably produced externally to the cells, and characteristic of the first stage of phthisis, although not invariably present under such circumstances.
IV. CREPITATION consists of more numerous and finer sounds than crackling. It is also confined to the period of inspiration, and is probably due to viscid secretion in the cell-walls, occasioning difficulty in their expansion. It is peculiar to pneumonia.
V. VIBRATIONS. Of sonorous, grave, or cooing, and sibilant, shrill, or whistling rhonchus; (sounds resulting mainly from vibration, and indicating flattening or narrowing of tubes, such as is common in chronic bronchitis,) it may be sufficient to remark that, when occurring interruptedly, these rhonchi may be occasioned by vibrations of air, probably produced by the intervention of pellets of mucus, as is sometimes observed in pertussis ; but that, in proportion to the persistency of these sounds, there is reason to suspect turgescence or thickening of the membrane, or effusion in the submucous tissue.
A few incidental remarks may here be expedient, in order to explain a little more particularly the modifications above suggested.