Fluid deficit in equine colic: Retrospective study of 583 horses with different types of colic

A retrospective study was performed on 583 horses with colic based on clinical findings and blood parameters to compare the severity of different gastrointestinal diseases such as spasmodic colic, left ventral large colon impaction, large colon displacement, small intestine and large colon strangulation obstruction or acute colitis. Based on laboratory analysis (PCV, base excess, sodium, chloride) and increased heart rate fluid deficit was calculated. Horses with spasmodic colic or left ventral large colon impaction showed no changes in blood analysis. Usually they do not need a fluid supplementation. Horses with large colon displacement and a heart rate >60/min have an intravascular fluid deficit of three to seven liters as well as a sodium bicarbonate deficit of 250 mmol. Horses with large colon strangulation need at least seven liters, but horses with a heart rate >80/min should get 20 to 27 liters of fluid and 500 to 1800 mmol sodium bicarbonate. Horses with small intestine strangulation obstruction need at least five liters of fluid, but horses with a heart rate >80/min should get seven to 20 liters of fluid for hydration and 400 to 1000 mmol of sodium bicarbonate. Horses with acute colitis have independently of heart rate a fluid deficit of six to 17 liters and horses with a heart rate >70/min need as many as 1100 mmol sodium bicarbonate for acid-base balance.