Assessment of the necessity for surgical intervention in cases of equine colic: a retrospective study.

The present study retrospectively examined clinical and clinicopathological findings in horses with colic to determine which variables distinguished between medically treatable cases and cases which required surgical intervention. Heart rate, haematocrit, haemoglobin concentration, blood erythrocyte count, frequency of borborygmi and degree of mental depression showed the greatest differences (P less than 0.001) between medical and surgical groups. However, some variables which primarily evaluated cardiovascular function, ie, blood pressure, oral mucosal capillary refill time and blood lactate concentration, were not significantly different between medical and surgical groups. When several of the following findings are observed together surgery is suggested: moderate to marked colic signs; tacky to dry oral mucosa which is discoloured (especially when brick-red or blue); decreased to absent borborygmi, probably associated with absence of rectal faeces; nasograstric intubation producing refluent fluid; leucocytosis with a left-shift; and tachypnoea, tachycardia, elevated haematocrit, hyperglycaemia and uraemia.