CHAPTKR XIII. 



PERICARDIUM. 



ANATOMY. PERICARDITIS WITH EFFUSION. 

 OPERATIONS. 



Anatomy. The pericardium is a fibro-serous sac 

 enclosing the heart and is situated between the pleurae. 

 It has, in front, the following structures : The remains of 

 the thymus gland ; the anterior margins of the lungs ; the 

 lymphatic structures and areolar tissue ; the internal mam- 

 mary arteries, and the triangularis sterni muscle. Be- 

 hind, it rests on the aorta, the bronchi and the oesophagus, 

 while, laterally, the phrenic nerves and the phrenic vessels 

 lie between it and the pleurae. Its base rests upon and is 

 attached to the central tendon and to some of the adja- 

 cent muscular tissue of the diaphragm, while its apex is 

 directed upwards and surrounds the great vessels. That 

 part of the thoracic % wall in front of it, is composed of the 

 sternum with the third, fourth, fifth and sixth costal car- 

 tilages on the right side, and the corresponding cartilages 

 with portions of the ribs on the left side. The pericar- 

 dium consists of two layers an external fibrous and an 

 internal serous layer, and where the bloodvessels pierce 

 the pericardium the fibrous layer ensheathes them and 

 blends with their outer coats. In the case of the aorta, 

 this projection of the fibrous layer of the pericardium over 

 the vessels becomes continuous with the cervical fascia, 

 which is prolonged downwards from the neck, so that the 

 cervical fascia holds up the pericardium and the pericar- 

 dium supports the diaphragm to which it is attached. 

 The serous layer of the pericardium is reflected onto the 

 vessels as they pierce the pericardial sac, and passes 

 along them to the heart, which it surrounds. The con- 

 nection of the deep cervical fascia with the pericardium 



