[Examination of horses with acute colic - clinical pathology and diagnostic imaging]

The article summarizes the relevant clinical pathological assessment of horses with acute colic. A minimal laboratory evaluation should include the patient's haematocrit (or packed cell volume), total protein, and lactate concentration in the blood. Haematocrit and total protein provide an indication of the severity of dehydration (haematocrit < 0.45 l/l is evidence of no to mild dehydration whereas > 0.5 l/l points to a severe dehydration). The degree of dehydration is often associated with the severity of the colic. Additionally, the blood lactate concentration rises with increasing intestinal compromise with a concentration of > 4 mmol/l indicating a guarded prognosis. However, it is crucial to assess laboratory values only in the context of the clinical findings. If an abdominocentesis is performed, the leukocyte count and the protein and lactate concentrations offer valuable information regarding the type of colic, the severity of the lesion, further therapy, and prognosis of the colic. Reddish discolouration of peritoneal fluid may be a sign of a strangulating obstruction. Transcutaneous abdominal ultrasonography may provide a crucial insight into the colic cause and severity in a relatively short time, even for inexperienced examiners. In regards to small intestinal lesions, dilated small intestinal loops can often be imaged ultrasonographically before they can be palpated transrectally. The occurrence of free peritoneal fluid and dilated small intestine as well as the evaluation of the intestinal wall and the extent of the gastric wall, allow a better management of the acute colic patient. In ponies and foals, radiography as a further diagnostic imaging modality of the abdomen is of great value. It can help to visualise sand impactions, meconium impactions, or gastrointestinal atresia in the neonate.