INSPECTION OF THORACIC CONTENTS 17 



Constant recourse should be had to warm squeezed-out pledgets of cotton- wool from 

 the Einger-Locke fluid as swabs for removing blood which has obscured the structures 

 in the wound. If for any reason you have to pause at some stage of operating, cover ' 



the exposed tissues with a warm squeezed-out swab to prevent cooling and drying of 

 them. Use freely the clip-weights for retracting the edges of the wound. 



The threads which are used for passing under vessels and nerves should be wetted 

 in the saline before being so used ; a dry thread passes less easily and drags on and 

 disturbs the tissues more. 



The bleeding from larger vessels, especially from arteries, requires artery-clamp 

 forceps, two pairs of which are provided. Usually it is enough to leave the clamp 

 forceps on for a few minutes, after which, on removal of the forceps, the bleeding- 

 point will be found to have closed ; if not, the bleeding-point should be ligated with 

 a thread applied while the artery-forceps are still hanging on to it ; the artery-forceps 

 can then be removed. 



While you do the operative dissection, your colleague, besides helping at the time 

 of insertion of cannulae, &c., should swab for you, deal with points of haemorrhage, 

 retract, supervise the ventilation, &c. 



ly. Place the preparation fully supine with all four limbs extended with Obs. 10. 

 a clip- weight attached to each foot. The chest can be stayed from rolling over inspection of 

 by propping with a hot- water bottle laid either side, the bottle being kept from beating heart 

 slipping by a small wool pledget, jammed under its outer edge. Feel for the w situ. 

 junction of the 3rd costal cartilage with sternum. From this level make a 

 skin incision (PI. I, figs. 1, 2, 3) along mid-ventral line to nearly as far as 

 half-way down the xiphoid process of the sternum. Across the anterior and 

 posterior ends of this incision make transverse ones extending 4 cm. to the 

 animal's right side, 3 cm. to left. Reflect the skin to either side ; then reflect 

 the pectorals, and then the recti muscles, and retract with four clip-weights. 



Feel for the 7th costal cartilage joining sternum on right side ; pass 

 closely under it, 3-5 cm. from the sternal edge, a string by means of the eye- 

 pointed packing-needle (PI. I, fig. 2). Tie the string tightly round the 

 cartilage. Ligate in this way in succession the 7th, 6th, 5th, and 4th rib 

 cartilages of the right side, close to their junction with their ribs. With 

 strong scissors cut the cartilages close to the sternal side of the ligatures, and cut 

 also the soft tissues in the same line from 7th space to 4:th inclusive. These 

 ligatures prevent bleeding from the intercostal arteries. Raising the sternal 

 edge of this incision, look under the sternum for the right internal mammary 

 artery. From the right 4:th intercostal space pass the rib-needle transversely 

 across under the sternum and deep to both internal mammary arteries, 

 bringing the ligature out through the 4th left space. Ligate the sternum 

 tightly, occluding the internal mammaries. Cut through the base of xiphoid 

 and 7th, 6th, and 4th left costal cartilages and their soft attachments, and 



2131 D 



