PNEUMOPERICARDIUM. 411 



time, in the German Clinic), in which pneumopericardium arose aftei 

 perforation of the pericardium by carcinoma of the oesophagus. Other 

 cases have been reported of perforation of the pericardium by ulcers of 

 the stomach, cancer of the stomach, or superficial cavities in the lungs. 

 Finally, gas sometimes is generated in the pericardium, by the decom- 

 position of the effusion which it contains. 



Upon post-mortem examination, the pericardium is usually much 

 distended, partly by air and partly by a purulent or sanious liquid. 

 The latter is the product either of a recent pericarditis, caused by the 

 entrance of air, or cancerous discharge, or of broken-down pulmonary 

 tissue, into the pericardial sac, or else, if the pneumopericardium be 

 the result of a generation of gas from a putrefying exudation, of a peri- 

 carditis of long standing. Upon puncture of the distended sac, the air 

 usually escapes with a hissing sound. 



Pneumopericardium is far less common than pneumothorax, and 

 nearly always is easy of recognition. It is true, the subjective symp- 

 toms, arising from perforation of the sac and of entrance into it of air 

 and debris of the tissue, are not very characteristic. Besides, the oc- 

 currence is usually attended by severe collapse, in which the patient 

 lies in a state of apathy, making no complaint, and, if questioned, re- 

 plying with hesitation and incompleteness. Even at some distance 

 from the patient a peculiar, clear, splashing sound can be heard, which 

 comes and goes with short, rhythmical intervening pauses, and which, 

 beyond all question, is caused by the agitation produced in the liquid 

 contents of the pericardium by the movements of the heart. In my 

 case this splashing sound was distinctly audible to the room-mates of 

 the patient, who lay at the other end of the ward. Upon inspection, 

 if the thorax still be flexible, the prominence of the cardiac region and 

 the obliteration of the intercostal depressions are very marked. The 

 cardiac impulse is indistinct or imperceptible. Upon percussion, there 

 is no cardiac dulness, and, indeed, the percussion-sound about the re- 

 gion of the heart is extremely full, clear, and tympanitic, often having 

 a distinct metallic ring. Upon making the patient sit up, or upon 

 making him bend forward, the beat of the heart becomes somewhat 

 more perceptible, and, as the air now rises and the liquid presses for- 

 ward, the former clear sound is replaced by a dull one. Upon auscul- 

 tation, either nothing can be heard excepting the above-named metallic 

 splashing, or else we may also hear feeble heart-sounds and friction 

 sounds. 



With exception of cases of traumatic origin, this disease, as a rule, 

 rapidly proves fatal. The collapse and severe pericarditis which 

 almost always accompany pneumopericarditis sufficiently account for 

 this. Recovery from traumatic pneumopericardium has been observed 



