Aspirin intoxication caused a mixed acid base disturbance. Stimulation of the central respiratory center in the medulla leads to a respiratory alkalosis. Metabolic acidosis can be severe and is caused via several mechanisms. Uncoupling of oxidative phosphorylation leads to an increase in oxygen use and CO2 production. Pyruvate and lactate are by-products of anaerobic respiration. Increased CO2 increases the respiratory rate further. It also causes the kidneys to increase excretion of bicarbonate causing a metabolic acidosis. Additionally the Krebs cycle is disrupted leading to increased lipolysis and gluconeogenesis. The by-product of these pathways is increased ketone production, which contributes to the acidosis. Of note, children typically do not develop respiratory alkalosis with salicylate intoxication: they usually present with only a metabolic acidosis. Treatment should be aggressive. Charcoal is indicated in a patient with an adequate mental status. Avoid intubation if possible, as deaths have resulted from inadequate ventilation. Treat dehydration with a bolus of 1–2 L of normal saline. Use intravenous bicarbonate to alkalinize the urine; potassium repletion is important, as a psuedohypokalemia will develop. Closely monitor both serum and urine pH. Hemodialysis is indicated for a salicylate level greater than 100 mg/dL in an acute ingestion, or >60 mg/dL in a chronic ingestion, volume overload (pulmonary edema, renal failure, CHF), altered mental status, severe academia, or lack of improvement with IV fluids and bicarbonate. A 40-degree right axis deviation manifested by a terminal r wave in AVR on ECG is seen in tricyclic antidepressant overdoses. Lithium toxicity is manifested by tremor, vomiting, diarrhea, lethargy, and seizures. It is not usually associated with fever and tachypnea. Increased intracranial pressure causes hypertension and bradycardia via the Cushing reflex.