TDK conference 2008

Hypothesis: Our hypothesis was that postoperative loss of appetite, depression, teeth-grinding, transient colic symptoms and slow recovery observed in a number of our equine clinical patients after surgeries are caused by Equine Gastric Ulcer Syndrome. Perioperative stress, feeding, treatments, drugs, some aspects of general anaesthesia can act as ulcerative factors.

Materials and methods: We examined 18 horses of different breeds, with age between 3-12 years. General anaesthesia was used with the same protocol in each case. During inhalation anaesthesia in recumbent position spent time varied between 60 and 270 minutes. Perioperative treatments consisted of NSAIDs for 3 days postoperatively in 17 horses, antibiotics in all horses and use of prokinetics and infusions in the 2 colic patients. Gastroscopy was performed before or immediately after surgery, then 48 hours after surgery and in 6 cases 7 days after surgery. The scoring system developed by the Equine Gastric Ulcer Council was used to evaluate the lesions found. Student t-test and analysis of variance were used for statistical analysis.

Results: 61.6% of the 18 horses arrived to the clinic with lesions, which reflects the international data of the EGUS prevalence in a mixed horse population. In 13 (72.2%) cases we have found worsening of lesions after 48 hours postoperatively. Significant negative change between pre- and postoperative examinations on the non-glandular (p=0.000549) and the pyloric (p=5.89x10E-05) region could be observed. Between the examinations performed after 48 hrs and 7 days marginally significant negative change was seen on the non-glandular region (p=0.070489) and significant on the pylorus area (p=0.02029). We have not found lesions on the glandular area except the lesions affecting the sensitive pylorus area.

Discussion: Perioperative period and general anaesthesia has negative effect on gastric mucosa causing EGUS. We suppose from our results that except colic operations the occurrence and severity of ulcers does not depend on the type of surgery, maybe rather on the length of general anaesthesia and time spent in recumbency. To prove this supposition further examinations would be necessary. As ulcerogen causative agents we can think of perioperative food deprivation and non-optimal feeding protocols, abnormal body positions in recumbency during general anaesthesia causing change in the normal abdominal pressures and anaesthetic agents affecting both the local mucosal circulation and gastrointestinal motility. Use of NSAIDs and stress may have less detrimental effect then supposed before, because main lesions were found on the non-glandular not on the glandular region.

Conclusions: When any sign indicates, gastroscopy should be the part of postoperative management protocol in equine clinics. To reduce number of clinical days, medication period, to enhance recovery and reduce prevalence of postoperative complications a gastric protectional treatment should be used routinely perioperatively even in cases of so simple surgical procedures as castrations. According to our gastroscopy results on the 7th day after surgery, these lesions and ulcers do not heal without special gastric treatments.