ANESTHETIC CONSIDERATIONS IN PATIENTS WITH ACIDOSIS
Acidemia can potentiate the depressant effects of most sedatives and anesthetic agents on the central nervous and circulatory systems. Because most opi-oids are weak bases, acidosis can increase the frac-tion of the drug in the nonionized form and facilitate penetration of the opioid into the brain. Increased sedation and depression of airway reflexes may pre-dispose to pulmonary aspiration. The circulatory depressant effects of both volatile and intravenous anesthetics can also be exaggerated. Moreover, any agent that rapidly decreases sympathetic tone can potentially allow unopposed circulatory depression in the setting of acidosis. Halothane is more arrhyth-mogenic in the presence of acidosis. Succinylcholine should generally be avoided in acidotic patients with hyperkalemia to prevent further increases in plasma [K+].