102 VAGINAL OVARIOTOMY IN THE MARE. 



canal with the same. After thorough disinfection of the 

 hands and arms remove the disinfectants by washing in 

 sterile soda solution, which at the same time renders the 

 hand unctuous and readily introduced through the vulva. 

 Armed with the guarded sterilized scalpel, Fig. 10, intro- 

 duce the right hand into the vagina promptly and when it is 

 well "ballooned" unsheath the knife and placing it just 

 above'the os uteri at I, Plate XV, parallel to the long axis 

 of the uterus and a few mm. to the right or left of the median 

 line, in order to avoid a loose fold of mucous membrane gen- 

 erally existing directly on the median line, the blade being 

 held vertical, that is the cutting surface parallel to the longi- 

 tudinal muscular fibers of the vagina, and guarding the pos- 

 sible extent of its introduction with the thumb and fingers, 

 push it directly forward in a straight line with a quick thrust 

 through vaginal mucosa, the muscular walls and the peri- 

 toneum, until the disappearance of resistance indicates that 

 the peritoneum has been penetrated. This is the most criti- 

 cal step in the operation. 



If the hand is introduced immediately after the injection 

 of the sterile saline solution the vagina will generally be 

 found " ballooned " or will quickly become inflated under 

 movements of the hand. If the solution is thrown out the 

 vagina may collapse and closely invest the hand, in which 

 case more soda solution should be injected when it will again 

 dilate. If the hand is introduced without the knife, with- 

 drawn and then introduced with the knife it will be frequently 

 found that the vagina has collapsed and needs a second fill- 

 ing with the fluid. Patience until dilation is accomplished 

 and promptness to act when attained are prime requisites 

 to success. The knife should be pushed through the vagina 

 quickly making a clean wound the width of the knife blade, 

 when the latter is to be withdrawn and laid aside. It should 

 be remembered that in this " ballooned " state, the anterior 

 wall of the vagina is but 2 or 3 mm. thick and easily pene- 

 trated. Introduce the hand again, push one finger into 



