COHORT RETROSPECTIVE STUDY ON DIAGNOSIS AND OUTCOME OF COLIC SYNDROME IN HORSES: PRELIMINARY DATA

Colic syndrome enrolles several disorders mainly involving the gastrointestinal apparatus and is a common cause of morbidity and mortality [1,2]. Several parameters are considered as predictor factors for the outcome, due to the multifactorial nature of the disorder and variability in horse population [3-6]. Aim of the study was to describe the characteristics, the clinical findings, diagnosis, treatment, and short term survival of horses referred for colic syndrome to the Veterinary Teaching Hospital of Teramo from 2005 to 2022. Collected data included patient signalment (age, gender, body weight, breed), time (morning, afternoon, night) and season of referral, type of treatment (medical, surgical), PCV, Total Protein, euthanasia, survival to discharge. Statistical analysis was carried out with R [7]. Frequency distribution of all discrete variables was provided as well as media, standard deviation (SD) for normally distributed continuous variables, median and interquartile range (IQR) for not-normally distributed continuous variables. One-hundred and fifty-seven horses were included (median age 10 years, IQR 7-13; body weight 550 kg, IQR 407-650). Thoroughbreds, Standardbreds, American and Spanish breeds were represented, as well as Frisian and Italian draft horses. Sixty-two were females (39.5%), 42/157 males (27%), 43/157 geldings (27.5%), 10/157 cases were unidentified (6%). Seventy-three were surgically (46,5%) and 81/157 conservativelly treated (51,5%), 3/157 cases were unidentified (2%). Thirty-nine were euthanized (25%), 5 died spontaneously, 106/157 survived to discharge (67%). In 7 cases the information was lost. When we considered as the outcome variable “survival to discharge”, only the explanatory variable”surgery” differed between the two groups. So a subdataset was considered involving only horses that were surgically treated. Horses receiving surgery were not different in age and body weight from those medically treated (t- test, p>0.05). Hour and season of referral were statistically different between survived and not-survived horses (Fischer exact test, p<0.05), with more survived horses referred in the afternoon and night, compared to the morning, and less survived horses refererred during winter compared to the other seasons. PCV was statistically lower in discharged horses (38.89% vs 48.17%), and time to standing after surgery shorter (58.61 vs 85.87) (t-test, p<0.05). In discharged horses recovery score was better, and not-ischemic lesions were more represented (38 vs 19)(Fischer exact test, p<0.05). No difference in discharge rate was observed according to the site of the lesion [large intestine 45/73 (61.64%), small intestine 22/73 (30.14%) or other sites 2/173(2.74%)], or to the administration of lidocaine after surgery (Fischer exact test, p>0.05). Overall success rate (survival to discharge) of this observational study was in accordance with previous data, with the most common diagnosis being large colon disorders. Differently, we did not observe a higher rate of survival with this disorder compared to others. Hour and season of referral varied among survived and not-survived horses. A more extensive analysis involving an univariate and multivariate logistic regression model involving physical parameter at referral may be of use to highlight odd ratio for survival and help the clinician in the evaluation of prognosis in case of exploratory laparotomy.