Management of Life-Threatening AcidBase Disorders

Adverse Consequences of Severe Alkalemia Severe alkalemia (blood pH greater than 7.60) can compromise cerebral and myocardial perfusion by causing arteriolar constriction, an effect that is more pronounced in respiratory than in metabolic alkalosis (Table 2).69–71 Neurologic abnormalities may ensue, including headache, tetany, seizures, lethargy, delirium, and stupor. The associated reduction in the plasma concentration of ionized calcium probably contributes to these manifestations. Although it exerts a moderate positive inotropic effect on the isolated heart, alkalemia reduces the anginal threshold and predisposes the patient to refractory supraventricular and ventricular arrhythmias. This arrhythmogenic action is more pronounced in patients with . . .