ABLATION OF SCIRRHOUS CORDS 307 



that of ablating exceptionally large scirrhous cords from 

 debilitated horses. 



RESTRAINT. — The horse is in the dorsal position with 

 the casting harness, and the hind legs are spread out so that 

 the inguinal region is accessible. General anaesthesia is 

 not only advisable but highly essential to the success of the 

 operation. In small unilateral scirrhous cord the partial 

 general anaesthesia of chloral hydrate (one to one and a 

 half ounces given as a drench one hour before operating) is 

 sufficient, but when the growth is so large and widely ad- 

 herent as to necessitate a long, painful dissection, chloro- 

 form anaesthesia can not be arbitrarily omitted. The oper- 

 ation is much too painful and of much too long duration to 

 be performed without general anaesthesia. The omission 

 is not only brutal but also invites fatal results from shock, 

 syncope, exhaustion from straining against the restraint, 

 haemorrhage and sepsis. 



On the operating table after the anaesthetic has been ad- 

 ministered the uppermost leg is drawn toward the ceiling 

 with a rope and the tail is tied backward to prevent switch- 

 ing into the field should the patient partially recover from 

 the anaesthesia during the operation. 



INSTRUMENTS.— The equipment is as follows: 

 i. Scalpels. 



2. Dissecting forceps. 



3. A number of artery forceps. 



4. A tumor grappling forceps or large tenaculum. 



5. Threaded needles for ligating vessels. 



6. Needle and thread to suture the incision. 



7. Large needle and thread to ligate the cord if 



found necessary by failure of the ecraseur to 

 crush it off. 



8. Ecraseur. 



9. Antiseptic solutions. 



TECHNIQUE.— First Step.— Disinfecting the Field.— 

 As the field is often covered with putrid secretion, some of 

 which is desiccated over the skin, a preliminary washing, 

 before casting, is advisable. After the patient is in posi- 

 tion the growth is squeezed with the hands to evacuate as 

 much of the pus in the sinuses as possible, and then the si- 

 nuses are irrigated with a strong solution of mercuric chlor- 

 ide. This precaution prevents the flow- of microbe-containing 

 pus into the surgical wound during the dissection. The 

 whole region is given, in addition, the usual surface cleans- 

 ing with soap, water and mercuric chloride. 



