Despite a bicarbonate deficit, bicarbonate replacement is not usu- ally necessary. In fact, theoretical arguments suggest that bicarbonate administration and rapid reversal of acidosis may impair cardiac function, reduce tissue oxygenation, and promote hypokalemia. The results of most clinical trials do not support the routine use of bicar- bonate replacement, and one study in children found that bicarbonate use was associated with an increased risk of cerebral edema. How- ever, in the presence of severe acidosis (arterial pH <.0), the ADA advises bicarbonate (50 mmol [meq/L] of sodium bicarbonate in 200 mL of sterile water with 10 meq/L KCl per hour for 2 h until the pH is >7.0). Hypophosphatemia may result from increased glucose usage, but randomized clinical trials have not demonstrated that phosphate replacement is beneficial in DKA. If the serum phosphate is <red.