Pig. Ii8. Anterior Thoracic Wall and Heart in the New-Born. 



From the fresh corpse of a iionnal Foetus tlie soft parts, of the Anterior Thoracic 

 Wall over the Sternum unci Costal Cartilages have been removed. The position 

 of the heart and its important parts has been determined by Luscmka's method, 

 (by the introduction of 6 needles). The heart and the great vessels are fully 

 shewn in the figure, the bones and muscles being imagined as transparent. The 

 outline of the Pericardium and the area of Absolute Cardiac Dtdness are yellow. 



The six points — indicated b}' Arabic figures — employed to determine 

 the position of the heart are : 



1. Internal angle of the first intercostal space on the right side close to 

 the Sternum : Right Pleura, Right Phrenic Nerve, Reflection of Pericardium, 

 Superior Vena Cava close to the right margin of the Arch of Aorta (this last- 

 named structure may be pierced by inserting the needle obliquely): in the adult 

 the Internal Mammary vessels would be injured, but not so in the child. Cf. Fig. 1 19. 



2. Internal angle of the 2nd intercostal space on the right side close to 

 the Sternum ; Right Pleura, Superior Vena Cava, upper border of Right Auricle. 

 Aperture of Pericardium. 



3. Internal angle of 2nd intercostal .space on the left side close to the 

 Sternum ; Region of Pulmonar\- and Aortic Valves (the pulmonar\- valves being 

 anterior, above and to the left ; ■ the Aortic posterior, below and to the right) 

 Cf. Fig. 1 20. The left pleura is opened by the needle. 



4. Middle line of Sternum at the level of the 4th Chondro-sternal articu- 

 lations or at a slightly higher level in the new-born: Border of Right Pleura, 

 Boundary between right auricle and right ventricle; Tricuspid Valve. 



5. Middle line of Sternum at the junction of the Manubrium with the 

 Xiphisternum : Lower border of right ventricle or of pericardium, and of the area 

 of Absolute Cardiac Dulness. 



6. Lower border of 5th rib on the left side at its costo-chondral junction 

 about ' -.th inch internal to the mammary hne: Apex of Heart, or more accurately 

 the limit between the left (red) and the right (blue) Ventricle. This needle 

 passed exactly through the Interventricular Septum without entering either 

 chamber of the Heart. 



ilie upper and lower parts of tlie Anterior Mediastinum are continuous 

 in the child; the Thymus which lies in front of the Pericardium reaches down- 

 wards between the Parietal pleurae as far as the area of Absolute Cardiac Dulness. 



The Anterior Mediastinum is filled up by Thymus, loose connective tissue, 

 fat, lymphatics and small vessels. 



