Effects of Carbicarb and Sodium Bicarbonate on Hypoxic Lactic Acidosis in Newborn Pigs.

BACKGROUND:Use of sodium bicarbonate (NaHCO3) may result in intracellular acidosis due to the generation of CO2. Carbicarb, has been reported to be superior to sodium bicarbonate (NaHCO3) because of lesser generation of CO2. The present study was designed to investigate whether Carbicarb or NaHCO3 is superior to normal saline in the treatment of hypoxic lactic acidosis.METHODS:Hypoxia was induced by ventilation with 8% O(2) in 30 piglets with fixed ventilation. When the pH fell to < 7.2, hypoxia was reversed by placing the animals in 21% O2 (experiment 1) or 100% O(2) (experiment 2) and either saline, Carbicarb or NaHCO3 were given. Data were collected for 120 minutes after therapy.RESULTS:In both experiment 1 (severe acidosis, pH < or = 7.1) and 2 (moderate acidosis, pH < or = 7.2) use of Carbicarb and NaHCO3 increased the arterial carbon dioxide tension (pCO2) significantly (p < 0.05). With moderate acidosis: 1) use of alkalinizing agents compared to saline resulted in an initial improvement in arterial pH at 1 minute, but thereafter, the differences were not statistically significant; and 2) there were no differences in hemodynamic variables and plasma lactic acid concentration between the three groups.CONCLUSIONS:The data demonstrate that 1) both Carbicarb and NaHCO3 significantly increase arterial pCO2; and 2) use of either alkalinizing agent in moderate acidosis does not alter the course of acidosis.