[Effects of NaHCO3 on cardiac function and metabolism during hypoxic metabolic acidosis--2: Rapid infusion of NaHCO3].
The effects of 1M sodium bicarbonate (NaHCO3) on cardiac function and myocardial metabolism during hypoxia were compared with those of 1M sodium chloride (NaCl) in anesthetized dogs. Metabolic acidosis was induced with inhalation of low fraction of oxygen (9%) for 2 hours. NaHCO3 (n = 9) or NaCl (n = 10) was infused intravenously in a half dose of 0.2 x body weight x base excess mEq in 30 seconds. This treatment was repeated five minutes later. In NaHCO3 group; with first infusion, both blood and intramyocardial pH increased. Left ventricular pressure (LVP) and maximum rate of rise of LVP (LV dP/dt max) were unchanged. Cardiac index (CI) tended to increase, while left ventricular end-diastolic pressure (LVEDP) and LVEDP/LVP increased significantly. In five dogs in which myocardial glucose uptake increased, LV dP/dt max increased. With the second infusion, inspite of the increase of blood and intramyocardial pH, LVP and LV dP/dt max decreased significantly compared with the preceding values. In NaCl group, with first infusion, blood and intramyocardial pH decreased. CI increased significantly, while LVP and LV dP/dt max tended to decrease, and LVEDP and LVEDP/LVP increased significantly. After the second infusion, myocardial contractility was depressed significantly. In both groups, blood lactate (LA) level increased significantly, especially with NaHCO3 infusion. LV dP/dt max correlated significantly with LA in NaCl group (r = -0.614, P < 0.001). However, in NaHCO3 group, LV dP/dt max did not correlate with LA. Blood glucose level (r = 0.612, P < 0.001) and myocardial glucose uptake (r = 0.718, P < 0.001) correlated significantly with LV dP/dt max in NaHCO3 group.(ABSTRACT TRUNCATED AT 250 WORDS)
Inoue
M
M
Department of Anesthesiology, Tokushima Prefectural Central Hospital.
Kohyama
A
A
D000142:Acidosis, Respiratory / Q000188:drug therapy / Q000378:metabolism / Q000503:physiopathology*; D000818:Animals; D004285:Dogs; D005947:Glucose / Q000378:metabolism; D007262:Infusions, Intravenous; D007773:Lactates / Q000097:blood; D009200:Myocardial Contraction / Q000187:drug effects*; D009206:Myocardium / Q000378:metabolism*; D017693:Sodium Bicarbonate / Q000008:administration & dosage* / Q000494:pharmacology
D007773:Lactates; D017693:Sodium Bicarbonate; D005947:Glucose