Page 607 - Equine Clinical Medicine, Surgery and Reproduction, 2nd Edition

582 CHAPTER 2

VetBooks.ir 2.180 2.181

Fig. 2.181 This horse had excessive swelling post
castration, which has led to ischaemic necrosis of the
scrotum. Note the residual swelling of the end of the
prepuce.

Fig. 2.180 Ultrasonographic image of a recently
castrated horse with excessive postoperative bleeding, within the dead space. Most cases are presented
revealing a large collection of blood trapped within with an obvious swelling or a change in discharge
the scrotum. The surgical incisions were enlarged, appearance and smell (e.g. purulent). Systemic signs
and drainage encouraged. may be subtle in the early stages, with depression
accompanied by a reduced appetite and pyrexia.
Haematological parameters will vary depending on
eventration and infection can all cause swelling the severity and time elapsed since the beginning of
and must be differentiated. In some cases, follow- the infection process.
ing closed inguinal castration, air gets trapped in Reopening surgical wounds is indicated when
the subcutaneous fascial planes during surgery and premature closure has occurred. Antibiotics might
accumulates in the scrotum; although of no clinical be indicated in more severe cases. In surgeries where
concern, this may be alarming to the owner. primary closure was performed, swelling can be
more prominent and systemic effects more severe,
INFECTION because drainage is not possible. In the latter cases,
treatment with antibiotics might be successful in the
The reported incidence of postoperative infection early stages, but if pockets of purulent material are
after castration varies from 5% to 20%. Strict aseptic present, establishing drainage by opening the scro-
surgery is difficult to achieve in field situations and tum is necessary to achieve a successful outcome.
ascending infection can also occur when the wounds
are left open. Although most infections respond well PERITONITIS
to treatment, they can become very serious if left
untreated. Studies have shown that a cellular inflammatory
response in the peritoneal cavity occurs after routine
LOCALISED INFECTION castration, mainly due to the presence of erythro-
cytes in this space following surgery. A more severe
The majority of infections are localised to the scro- response, and indeed a pathogenic one, is expected
tal and/or inguinal tissues and are mainly caused if infection tracks up the inguinal canal and causes a
by impaired drainage allowing bacteria to multiply septic peritonitis. The associated endotoxaemia will