AJP - Renal Physiology, Vol 249, Issue 5 630-F635, Copyright © 1985 by American Physiological Society
Metabolic effects of sodium bicarbonate in hypoxic lactic acidosis in dogs
H. Graf, W. Leach and A. I. Arieff
The metabolic effects of NaHCO3 therapy in hypoxic lactic acidosis were
evaluated in the anesthetized dog. Hypoxic lactic acidosis was induced by
ventilating the dogs with a hypoxic gas mixture of 8% O2/92%N2, resulting
in arterial PO2 of less than 30 mmHg, pH below 7.20, bicarbonate less than
12 mM, and lactate more than 7 mM. In this situation lactate accumulates
because of overproduction of lactate by gut and carcass in the presence of
a diminished capacity of the liver to extract lactate. After the
development of hypoxic lactic acidosis the dogs were treated for 60 min
with either NaHCO3 or NaCl or had no therapy. Sixty minutes of either
treatment resulted in further declines of blood pH and bicarbonate that
were similar in all three groups. NaHCO3-treated animals, however, showed
an increase in blood lactate that were significantly higher than those
treated with NaCl or those that had no therapy. This could be explained by
a significantly higher gut lactate production with NaHCO3 therapy than in
the NaCl-treated group. Concomitantly NaHCO3-treated animals showed a
decrement in liver and gut blood flow that did not occur with NaCl
treatment. Only NaHCO3 therapy was associated with a further decrease of
liver intracellular pH, which could be attributed to both an increase in
the CO2 load to the liver and increased tissue lactate levels, which were
not observed with NaCl or no therapy. Additionally, liver lactate
extraction was not improved by administration of NaHCO3 or NaCl.(ABSTRACT
TRUNCATED AT 250 WORDS)
