Outcome and long-term follow-up of 20 horses undergoing surgery for caecal impaction: a retrospective study (2000-2008).

REASONS FOR PERFORMING STUDY: If untreated, caecal impaction may progress to rupture of the caecum and reports of long-term outcome for horses undergoing surgery for caecal impaction are required. OBJECTIVES: To describe short- and long-term complication rates for horses undergoing surgery for caecal impaction in an otherwise life-threatening gastrointestinal condition. METHODS: Case records were reviewed for horses undergoing surgery for caecal impaction. Horses were included in the study if an abnormally large, fluid-distended or feed-impacted caecum was the primary diagnosis at surgery and excluded if the caecum had already ruptured upon opening the abdomen, necessitating euthanasia. Short-term follow-up data were obtained from clinical records; and included complications, repeat celiotomy and survival to discharge. Long-term survival was defined as survival for >1 year post operatively. Long-term follow-up data were obtained through telephone interviews with owners and referring veterinary surgeons. Survival, occurrence of post operative colic and subsequent use of the horse were recorded. RESULTS: Twenty horses underwent surgery for caecal impaction: 16 horses underwent caecal bypass (typhlotomy and removal of caecal contents, ileal transection followed by ileocolostomy); 3 underwent typhlotomy alone; and one horse underwent typhlotomy followed by a second procedure where caecal bypass was performed. Five horses (25%) were admitted for colic evaluation with primary caecal impactions, in 10/20 (50%) of cases the impaction was secondary to previous orthopaedic surgery and in 5/20 (25%) caecal impaction was identified at repeat celiotomy following a previous colic surgery. Sixty-five percent (13/20) of horses survived to discharge; 11/13 (85%) of horses discharged survived long term; 100% (3/3) horses that received typhlotomy alone were discharged and survived long term. CONCLUSIONS: The prognosis following caecal impaction surgery is fair, if the horse survives to discharge then prognosis for long-term survival is good. POTENTIAL RELEVANCE: Surgery for caecal impaction carries a fair prognosis for a potentially life threatening disease, in particular where caecal dysfunction is suspected.

Third eyelid resection as a treatment for suspected squamous cell carcinoma in 24 horses.

Between October 2000 and January 2007, 24 horses were presented with suspected squamous cell carcinoma (SCC) of the third eyelid. The hospital's medical records were analysed retrospectively to gain data about the cases, and telephone follow-up was obtained from the owners and referring veterinary surgeons. The resected third eyelid was submitted for histological examination in 21 cases; in the other three cases the tissue was not submitted at the owners' request, for economic reasons. SCC was confirmed in 16 of these 21 cases, three cases were diagnosed histologically as lymphoid hyperplasia, one as a mast cell tumour and one as a sebaceous gland adenocarcinoma. Long-term follow up over a median period of 41 months revealed no recurrence of SCC or associated problems; six of the 16 confirmed SCC cases were euthanased for unrelated reasons during the follow-up period.

Electrosurgery as the sole means of haemostasis during the laparoscopic removal of pathologically enlarged ovaries in mares: a report of 55 cases.

REASONS FOR PERFORMING STUDY: There is little published clinical evidence on the use of a laparoscopic approach for the removal of pathologically enlarged ovaries in standing mares. OBJECTIVES: To show the orders of success and complication rates that can be expected if pathologically enlarged ovaries are removed from standing, sedated mares under laparoscopic guidance using only electrosurgical means of haemostasis. METHODS: A retrospective analysis was made of 55 mares in which the removal of an enlarged ovary was attempted by applying a standard laparoscopic procedure for routine ovariectomy in standing mares including a reliance solely on one of 2 types of electrosurgical bipolar forceps with an integrated guillotine for haemostasis and transection of the ovarian pedicle. The outcomes and complications encountered were recorded. Logistic regression analysis was performed to identify the risk of any complications associated with the size of the ovary removed and the instrument used. RESULTS: In 54 of the 55 mares, the surgery was successfully accomplished by the planned approach. In one mare there was significant intraoperative haemorrhage and this necessitated the additional use of a prosthetic haemostatic device. The only other complications encountered were post operative abdominal discomfort (n = 9), delayed incisional wound healing (n = 6) and iatrogenic uterine puncture (n = 2). One mare developed a rectal tear, but not as a direct complication of the surgical procedure. None of these prevented a long-term successful outcome. CONCLUSIONS: The removal of pathologically enlarged ovaries (up to 30 cm diameter) from mares under standing sedation can be accomplished predictably and safely by applying the standard laparoscopic approach that is established for routine laparoscopic ovariectomy, including a reliance solely on endoscopic electrosurgery instruments for haemostasis of the ovarian pedicle. POTENTIAL RELEVANCE: This study shows that the simple standing laparoscopic technique now favoured for routine ovariectomy can be used safely and reliably for the removal of pathologically enlarged ovaries. This promises to be of significant clinical advantage to mares so affected.

Effect of age at presentation on outcome following arthroscopic debridement of subchondral cystic lesions of the medial femoral condyle: 85 horses (1993--2003).

REASONS FOR PERFORMING STUDY: Subchondral cystic lesions of the medial femoral condyle (SCMFC) are well documented in horses < or =3 years; arthroscopic debridement or enucleation of the cyst is currently the surgical treatment of choice. However, studies of occurence and outcome following surgery in older horses are lacking. OBJECTIVE: To identify factors important in outcome for horses with SCMFC treated by arthroscopic debridement. HYPOTHESIS: Age of horse at presentation has a significant influence on return to work following arthroscopic treatment for SCMFC. Clinical and diagnostic findings are also significant with respect to prognosis. METHODS: A retrospective review of medical records from 6 equine referral centres identified 85 horses that underwent arthroscopic debridement of SCMFC. Clinical examination, radiographic and arthroscopic findings were analysed together with follow-up data. Univariable analysis and multivariable logistic regression models were used to determine factors affecting return to soundness. Event-time analysis was performed to evaluate return to work. RESULTS: Older horses (>3 years) were less likely to return to soundness (P = 0.02) or to work (P = 0.04) than younger horses (< or = 3 years). Of 39 horses age 0-3 years, 25 (64%, 95% CI 49-79%) returned to soundness. Of 46 horses age >3 years, 16 (35%,95% CI 21-49%) returned to soundness. In addition, cartilage damage at sites other than the SCMFC negatively affected prognosis (P = 0.05). The hospital where treatment was performed had no influence on return to soundness. CONCLUSIONS: Older horses carry a worse prognosis for both return to soundness and return to work. POTENTIAL RELEVANCE: It is important for clients to be made aware of the difference in outcome between age groups.

Experiences in treatment of epiglottal entrapment using a hook knife per nasum.

Thirty eight horses with epiglottal entrapment were examined. In 29 the dorsally displaced mucosa was split axially with a curved hook knife, per nasum. The condition was also treated by subepiglottal mucosal resection (4 horses) and solely by the administration of an anti-inflammatory throat spray (4 horses). All surgical cases were treated with an anti-inflammatory throat spray and parenteral phenylbutazone. Those horses treated via a laryngotomy incision were box rested until the laryngotomy incision healed. The other horses were restricted to walking and trotting exercise for 10 days before endoscopic re-assessment. If the condition had resolved by this stage the horse was then returned to full exercise. Epiglottal entrapment was alleviated in 22 horses treated by axial section but it recurred in 4 and 3 cases were lost to follow up. Two of 4 cases were treated successfully but mucosal resection and 2 of 4 cases by Nd:YAG laser. Three out of the 4 horses treated medically also recovered. Of the 38 horses, 6 required a second operation and 2 had a third surgical procedure. Of the horses treated by axial section of the displaced mucosa, 14 ran successfully without a respiratory sound or obstruction and 4 won races. In conclusion, using the hook knife inserted via the nasal passages offers a safe, relatively inexpensive and successful method of treating epiglottal entrapment.

Use of a stapling device to aid in the ovariectomy of nine mares with a granulosa thecal cell tumour.

This paper describes the use of a linear stapling device as an aid to unilateral ovariectomy in nine mares with granulosa thecal cell tumours. The intraoperative and postoperative complications are described and follow up details on each case are presented.

Outcome of treatment in 23 horses with progressive ethmoidal haematoma.

This paper describes the outcome of treatment in 23 horses with an ethmoidal haematoma. In 22 cases a diagnosis could be made by endoscopic means alone but in 1 horse the lesion was confined to the maxillary sinus and a diagnosis was made only at surgery. One horse was destroyed at the owner's request but the other 22 underwent radical excision of the lesion via a facial flap approach under general anaesthesia. Post-operative haemorrhage was controlled by nasal packing with a gauze bandage and this was removed between the 2nd and 4th post-operative day. One horse died from encephalitis the day after surgery. Other complications included facial wound dehiscence, sequestration and suture periostitis. Of 21 horses followed up post-operatively there was definite recurrence of lesion in 2 cases and possibly a third. However, in 18 horses there was no evidence of recurrence (follow up times were 2 to 85 months). It is suggested that radical excision of the lesion provides an effective means of treatment.

Ileal intussusception in 16 young thoroughbreds.

The paper describes the outcome of 16 cases of short-ileal-ileal intussusception in young Thoroughbred horses. The intussusception was often associated with chronic or intermittent low grade abdominal pain. At laparotomy, only the intussusception was reduced in one horse; in another, a myotomy of the thickened stenosed intussusception was carried out after reduction. In 11 cases as ileocaecal bypass anastomosis was performed proximal to the intussusception after its reduction. One horse was subjected to euthanasia during operation because of irreversible intestinal wall damage and another because of intestinal rupture. One foal had a cardiac arrest following reduction of the intussusception. One horse was subjected to euthanasia 4 months post-operatively because of intractable abdominal pain caused by intestinal adhesions. Although several horses suffered episodes of post-operative abdominal pain, and 2 were subjected to a second laparotomy, 12 horses made an eventual complete recovery.

Some factors influencing plasma AST/CK activities in thoroughbred racehorses.

Sixty-six Thoroughbred horses in training (2 or 3 years of age) were studied during one flat racing season, to investigate the relationship between age, sex, time of year, dietary electrolyte imbalances and plasma aspartate aminotransferase/creatine kinase (AST/CK) activities. Management and training variations were minimised. Between February to October, monthly 24 h post exercise samples were collected and analysed for AST and CK activities. Sex and/or age were shown to have a significant effect on the occurrence of high CK (> 100 iu/litre) and AST (> 300 iu/litre) activities. Fillies were more likely to have elevated CK and AST than colts. Two-year-olds tended to have higher AST activities than three-year-olds. Time of year had no significant effect on the number of animals with high or low activities. Fourteen animals had consistently raised plasma AST activities (median > 300 iu/litre). Eight of these raced and seven won at least one race. The average daily intake of calcium, sodium, phosphorus and potassium was determined at each sampling time. In eight of the horses, the fractional electrolyte excretion (FE) of phosphate (PO4) and sodium (Na) was determined monthly. FE values were also determined in three horses which had suffered repeated attacks of the equine rhabdomyolysis syndrome. The FE, PO4 and Na values reflected dietary intake of calcium, phosphorus and sodium respectively. It was not possible to determine any effect of training or a predisposition to equine rhabdomyolysis. No obvious differences were found between the resting thyroxine values of three animals with consistently low AST activities, six of those with consistently raised AST and three animals which had suffered repeated attacks of rhabdomyolysis.

Outcome of treatment in 35 cases of guttural pouch mycosis.

This paper describes the outcome of treatment of 30 cases of guttural pouch mycosis by ligation of the internal carotid artery on the cardiac side of the lesion and lavage of the affected pouch with natamycin. Twenty-three horses recovered fully following this treatment while laryngeal hemiplegia persisted in one case and slight dysphagia caused by pharyngeal hemiplegia in another. The remaining five horses died or were destroyed. Five horses with guttural pouch mycosis, which had shown no epistaxis but had pharyngeal hemiplegia, were treated by topical natamycin alone. Only two of these survived, of which one remained slightly dysphagic. Ligation of the internal carotid artery of the cardiac side of the lesion is an effective means of reducing the chance of fatal epistaxis in cases of guttural pouch mycosis. Some cases of pharyngeal hemiplegia can make a complete recovery although it may take 12 to 18 months.

Condylar fracture of the cannon bone with axial sesamoid fracture in three horses.

The case histories of three young thoroughbred racehorses with displaced lateral condylar fractures combined with an axial fracture of the lateral sesamoid bone are described. In two cases the condylar fracture was repaired surgically but both horses developed severe degenerative joint disease and remained lame. The third horse was destroyed humanely. It is important that axial fractures of the sesamoid bone are recognised so that a poorer prognosis can be given for treatment of condylar fractures in racing thoroughbreds.

Barium swallow as an aid to the diagnosis of grass sickness.

Twenty-five horses, suspected on clinical grounds of having grass sickness, were given a barium swallow. Using image intensification the passage of the barium bolus was followed radiographically from the pharynx to the stomach. All 18 horses in which grass sickness was later confirmed at post mortem examination showed defective oesophageal motility. Although the specificity of the abnormality could not be proven, the technique offers a valuable aid to the ante mortem diagnosis of grass sickness.