Horse blood bicarbonate

Consider the measurement of bicarbonate (HCOJ) in the blood of racehorses. Some trainers injected NaHC03 into a horse prior to a race to neutralize lactic acid that accumulates during strenuous activity. To enforce a ban on this practice, HCO3 in horse blood is measured after a race. When a manufacturer stopped making an instrument that was certified for such measurements, authorities needed to certify a new instrument. 

B. Bicarbonate in replicate samples of horse blood was measured four times by each of two methods with the following results ... 

It is the author s opinion that there are no grounds for using sodium bicarbonate to treat lactic acidosis, irrespective of the arterial (or venous) pH. This contradicts previous recommendations that it should be used when the pH decreases below 7.1 (Divers 1998) or 7.22 (Johnson 1995). The treatment of lactic acidosis with sodium bicarbonate is based on four suppositions low blood pH is directly harmful, sodium bicarbonate is able to increase blood pH when infused i.v., raising the blood pH with sodium bicarbonate improves patient status and any adverse effects of sodium bicarbonate are outweighed by its benefits (Forsythe Schmidt 2000). These suppositions are not supported by the data available currently in horses, humans and experimental animals. 

Bicarbonate does not increase left ventricular contractility during L-lactic acidemia in pigs. American Review of Respiratory Disease 148 317-322 Cooper D J, Walley K R, Dodek P M et al 1992 Plasma ionized calcium and blood lactate concentrations are inversely associated in human lactic acidosis. Intensive Care M icine 18 286-289 Corley K T T 2002 Fluid therapy for horses with gastrointestinal diseeises. In Smith B P (ed) Large animal internal medicine, 3rd edn. Mosby, St Louis, MO, pp. 682-694... 

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