Inspection.—In inspection of the chest the age of the patient is to be regarded in the interpretation of the appearances. In pericarditis with effusion we are apt to find a change in the shape of the chest—a bulging in the region of the heart, even though the effusion be somewhat small in quantity. This change is more apparent when it occurs in young persons, where the chest-walls are very elastic. In those advanced in years, in whom the costal cartilages are more or less ossified and the elasticity of the rib materially altered, or where the chest-walls are bound down by pleuritic adhesions, the shape of the chest may be materially altered and yet not be very apparent. The intercostal distension is in any case a matter for investigation. The chest shows a bulging in the pericardial region, slightly diminished by a dorsal decubitus and but little influenced by the acts of respiration.
Palpation.—This gives us an idea of the amount and outline of the tenderness, which is often found to correspond with that of the inflamed pericardium. It also enables us to determine to some extent the limit of distension of the pericardium, the location of the heart, and the shape of the sac. We also ascertain the impulse of the heart. Now, at first this is somewhat increased, although it is apt to be irregular. As effusion of liquid takes place, the heart is displaced generally backward and upward, and the impulse becomes indistinct or imperceptible. A slight wavy, irregular motion diffused over considerable part of the cardiac region may take its place.
Percussion.—During the dry stage, unless a very considerable amount of lymph be extravasated, the natural percussion dulness in the cardiac region is not appreciably altered. When the pericardium becomes distended with fluid the cardiac dulness increases markedly, particularly in a transverse manner; and as the pericardium is conoidal in shape, but its position the reverse of that of the heart, its base resting upon the diaphragm, with its distension a roughly pyramidal outline of dulness is found, the apex being near the root of the vessels, the base upon the diaphragm. A great deal of stress has been laid on this shape of the percussion dulness—much more, I think, than in point of fact is warranted, for it is not always to be distinctly made out. Rotch8 has called attention to the dulness being early manifest in the fifth intercostal space of the right side, and in all large effusions it is sure to extend across the sternum. It may, when the sac is much distended, reach as high as the first rib, as low as the seventh rib, and below the ensiform cartilage, and the line of the lower dulness may become continuous with that of the displaced liver. The dulness may extend on the left side backward almost to the spinal column and across the sternum to the right nipple. The dulness is somewhat influenced by position; changing from side to side alters the line of the fluid.
8 Boston Medical and Surgical Journal, 1878, vol. xcix.
Auscultation.—Pericarditis is not discoverable without the signs by auscultation, and it is the interpretation of these signs which enables us to distinguish the various stages. We must bear in mind that, roughly speaking, there is first a stage of suspension of the serous secretion, and consequent dryness of the pericardium; secondly, effusion of lymph or fibrin; thirdly, effusion of serum or sero-pus. Now, the question arises whether we can distinguish the first effect of the inflammation on the serous membrane, which, indeed, may be exceedingly short in duration, limited to a few hours. From the fact of there being a suspension of secretion and absorption of that which has been normally secreted, it becomes evident that, the parietal pericardium coming into direct contact with the visceral layer, certain sounds will be caused by the friction of the heart in its action. Can we discern them? Great differences of opinion have been expressed with reference to this; indeed, it has even been questioned whether sounds would be or would not be produced. Stokes doubted the competency of simple dryness of the pericardium to generate friction phenomena. Collin, on the contrary, held that this is actually the condition of the pericardium indicated by the new-leather sound. To this Walshe makes assent. Hayden9 says: "I have never met with a case which would warrant me in asserting that a state of simple dryness and vascularity of surface may give rise in the pericardium to veritable friction sound. I do not, however, deny the possibility of an occurrence which, theoretically, would seem not improbable. In every instance, without exception, in which I have had the advantage of determining by post-mortem examination of the body the condition of the serous surface of the pericardium, where friction sound of indubitable pericardial origin had existed during the patient's last illness, I have found lymph in greater or less quantity effused upon the surface." My own experience is entirely in accord with this. Theoretically, I grant the possibility. Practically, I have never seen it; and in the suspected cases lymph has always been found, with the single exception of a case in which the friction sound had disappeared nearly a week before death, which resulted from kidney lesion, and where it was reasonable to infer that the lymph had been absorbed.
9 Diseases of the Heart and Aorta, Philada., 1875, vol. i. p. 327.
The friction sound, then, is the sign of exudation. Since it was originally described by Stokes in 1833 it has been likened by different observers to familiar objects, such as the crackling of parchment and the new-leather sound. It is generally most evident at the base of the heart, is considerably influenced by pressure, is more often double than single, frequently resembles a double cardiac murmur, and justifies the name of a to-and-fro sound given to it by Watson. The friction sounds change from time to time according to the character, quantity, and stage of the exudation, ceasing altogether when adhesions have taken place or fluid has been effused, to return again as the fluid is absorbed, and to cease when recovery has taken place. They exhibit an inspiratory rhythm very much intensified by full inspiration. Although, as the place of election of the inflammation is at the base of the heart, we are apt to find the friction there earliest as well as longest, this is not invariable; for, as above stated, the morbid process may begin anywhere in the continuity of the pericardium.
Next to the friction sound, the most valuable signs in pericarditis are derived from the muffling of the cardiac sounds. This is particularly valuable in the stage of effusion, for prior, notwithstanding the friction phenomena are somewhat obscure, they do not render the sounds of the heart fainter to any material degree. The cardiac sounds become less and less distinct as the fluid increases. The heart sounds cease to be audible, just as is the case with the friction sound, from below upward, beginning to be indistinct at the apex of the heart. Gradually and lastly, the sounds of the aorta and pulmonary valves are lost, but not entirely, unless there be a large amount of fluid pushing up the pericardium at its attachment around the roots of the great vessels, and the second sound at these valves is scarcely ever wholly gone. Sudden effusions of large quantities of fluid are so rare that the progressive extinction of the cardiac sounds becomes an important element in diagnosis and prognosis. It has already been noted that the friction sounds linger around the base of the heart; this may happen with even considerable effusion. As regards the character of the fluid influencing the distinctness of the cardiac sounds, I think it may in general terms be stated that if the effusion be dense, sero-purulent, or purulent, the sounds of the heart are, in proportion to the size of the effusion, relatively more obscured than when this is thin.
DIAGNOSIS.—The diagnosis of pericarditis, as before remarked, cannot be determined by any but physical signs, and even these signs may not be sufficient for us to come at once to a positive conclusion: the refinement of perception necessary to detect and properly interpret the delicate changes which occur in some cases is still lacking to us. In reviewing the general diagnosis of pericarditis we must bear certain facts in mind. The acute malady has a very dissimilar origin. It usually sets in with a fever, ordinarily not of high grade, which may be preceded by a chill of differing intensity; the pulse is decidedly accelerated and of varying regularity, not uncommonly strikingly irregular; on the other hand, the nervous phenomena may be the most prominent. Craigie10 observed long ago in a case of pericardial inflammation in a girl of fourteen that the only prominent symptom besides the symptom of fever was constant tossing of the extremities and person, jactitation similar to the motions of the dance of St. Vitus. Roeser of Bartenstein observed the same symptom in a child of nine years. There is at times early delirium, very frequently considerable restlessness, with more or less of an anxious expression of countenance. Quickened rather laborious breathing is often early observed, and so is pain in the præcordial region directly under or near the sternum, perhaps extending to the left shoulder, acute, severe, and shooting, increased by pressure and motion, and, as Peter11 has pointed out, associated with pain in the phrenic nerve, elicited by pressure between the two insertions of the sterno-mastoid and also found on each side of the xiphoid appendix. But the pulse may be regular, the breathing not perceptibly accelerated or laborious, and even the important symptom, pain, may be wanting from the beginning to the end of the disease. This occurs in the so-called latent cases.
10 Elements of the Practice of Physic, Edinburgh, 1837, vol. ii. p. 151.