550 OBSTETRICAL OPERATIOXS. 



generally adopted when, after removal of one or more of the limbs, the 

 body of the foetus still remains fixed in the genital canal — as in sterno- 

 abdominal and sterno-lumbar presentations ; by it we obtain a con- 

 siderable diminution in the dimensions of the body, more room for 

 manipulation and version, and perhaps, next to the removal of the limbs, 

 it is the most useful operation in embryotomy. 



As we have said, evisceration of either of the cavities may be practised, 

 according to circumstances. We shall, therefore, describe the mode of 

 reducing the volume of both — thorax and abdomen. 



Thoracic Evisceration. 



This operation is sometimes practised in the anterior presentation 

 when the thorax of the foetus is too large, and may be performed inde- 

 pendently of abdominal evisceration. The chest is emptied of its con- 

 tents first, when the anterior part of the foetus is in the passage. The 

 head and limbs should be corded — if one of the latter is removed all the 

 better ; if not, the cords should be pulled well upwards, in order to 

 make more room between them. Should the head be an obstacle to the 

 performance of the operation, it may be amputated ; but if it is back in 

 the uterus, then it may be left there. A strong scalpel with a long 

 handle, the fingei--scalpel, or either of the two embryotoms shown in 

 Figs. 200, 201, is the best instrument. It is passed carefully into the 

 vagina until the hand reaches the breast of the foetus, when the blade 

 is thrust deeply into the chest, between the two first ribs, and as close 

 to the spine as possible, cutting down towards the sternum and upwards 

 to the vertebrae. 



The knife is now dispensed with, and the hand being re-introduced, 

 the fingers are pushed into the chest and the two first ribs removed, 

 thereby allowing sufficient room for the whole hand to enter the cavity. 

 The lungs and heart are torn away from beneath the spine, and, with 

 the thymus gland, removed from the uterus. The chest collapses a 

 good deal, but if the foetus cannot yet be extracted, the hand may be 

 pushed through the diaphragm, and the contents of the abdomen carried 

 away through the chest. 



Some operators, instead of opening the thorax in front, incise from 

 two to five of the ribs close to the sternum, and pass the hand into the 

 chest by the aperture so made. Others divide the ribs on both sides, 

 and remove the sternum as well as the viscera. It will often be found 

 that the contents of the chest and abdomen can be removed without 

 cutting the ribs. 



Abdominal Evisceration. 



Evisceration of the abdomen may be effected, as just stated, through 

 the thorax, by tearing away the diaphragm. 



But in the posterior or adominal presentations, and indeed in any 

 presentation or position in which this region is accessible to the hand, 

 eventration can be performed. Nevertheless, it is not always easy ; on 

 the conti'ary, it is sometimes most difficult and dangerous. 



Either of the embryotoms used for evisceration of the chest may be 

 employed for the abdomen. 



The edge of the instrument is applied to the wall of the cavity, which 

 is incised by drawing the hand towards the operator. Then the whole 

 of the viscera are torn away, and, if need be, that of the chest also, 

 through the diaphragm 



