Equine Health Update EHU Vol 20 Issue 02 | Page 17

CPD Article | EQUINE Small intestinal eventration usually occurs within 4 hours of castration, although it can occur as late as 12 days post-surgically. Signs of severe colic will follow due to strangulation of the intestine. The eviscerated intestine should be preserved from trauma by applying a large cloth or towel in sling-like fashion (like a nappy). (If only a small piece of the intestine is protruding, it can be cleaned and placed into the scrotum, after which the incision is sutured closed as a temporary measure to prevent trauma to the intestine). 1,3,10 These patients should receive broad spectrum antibiotic cover and referred to a surgical facility immediately. 3 Survival rates after surgical intervention ranges from 36-87% 3 , depending on the amount of intestine involved, the viability of the intestine or resection thereof, and the duration of the strangulation. 11 Standard midline colic surgery (versus inguinal approach only) also increases the chances of survival, as this allows for proper evaluation and resection/anastomosis if needed. 12 Preputial and Scrotal Oedema Scrotal and preputial swelling occurs after nearly every castration. Making a large scrotal incision or removing a large portion of the scrotum will increase post-operative drainage which will decrease the swelling, as will post-operative exercise from 24 hours after the surgery. 1,10 A wound which seal too quickly should be opened using a sterile instrument (e.g. large curved artery forceps) or gloved fingers to establish adequate drainage. Occasionally it might be necessary to enlarge the incision to ensure continued drainage. Strict asepsis should be adhered to which will decrease the chance of iatrogenic infection. Exercise and the administration of NSAIDs should also be part of the treatment regime. 1,6,10 Although hydrotherapy with cold water hosing on the scrotum is a well-established part of post castration management, it has been associated with increased swelling. 6 Continued swelling despite adequate drainage and exercise should alert the clinician to the presence of infection. 1 Surgical Site Infection Surgical site infection may become apparent days to years after castrations. It can be caused by a dirty instrument, break in aseptic surgical technique during the procedure or post-operative contamination. Inadequate drainage and ligatures will also predispose to infection. 1,3,10 The clinical signs of infection include excessive swelling, pyrexia, hind limb lameness, pain on palpation and a purulent discharge. Treatment consists of providing adequate drainage, exercise, NSAIDs and antimicrobial therapy. 1,3,10 Septic funiculitis may be caused by extension of a scrotal infection, inadequate drainage or dirty instruments. It is associated with open castrations where the parietal tunic and cremaster muscle are not removed, and with the use of a ligature. 1,3,10 Scirrhous cord is a chronic septic funiculitis often caused by Staphylococcus sp. Although the scrotal wound has healed, the infected stump continues to enlarge. On palpation a hard longitudinal mass will be present in and adhering to the scrotum. Treatment consists of removal of the infected stump under general anaesthetic. 1,3,10 Excessive granulation tissue infected by Streptococcus sp., protruding from the wound that looks like a mushroom, with a purulent discharge is called champignon (the French word for “mushroom”). Before the invention of the emasculator that crushes and cuts the cord, ligatures were used to control haemorrhage. These formed a nidus for the streptococcal infection. Since the use of these ligatures were discontinued, this form of septic funiculitis has become virtually historical. 3,10 In rare cases, the infection may also extend into the peritoneal cavity to form an inguinal abscess. Clinical signs includes pyrexia, weight loss and oedema. The mass will be palpable on rectal examination. These cases are very difficult to treat and are often euthanized. 8 • Volume 20 Issue 2 | July 2018 • 17