Case Reviews Our flight team was called to a local hospital to transport a 2-week-old boy diagnosed with hypernatremic dehydration to our pediatric intensive care unit (PICU). Because of the close proximity to our base, this transport was done by ground ambulance. This patient had pre sented to the referring hospital 5 hours before our arrival with mild to moderate dehydration manifested by dry skin and a sunken anterior fontanel but with good skin turgor, pink color, moist mucous membranes, and brisk capillary refill. He had protective airway reflexes with a good respiratory effort and good air exchange. Laboratory tests drawn after the placement of a 22-gauge peripheral intravenous line revealed a venous pH = 7.26, p0, = 40 torr, Na = 200 mEq/L, K = 5.0 mEq/L, and glucose = 84 gm/dL. He then was bolused twice with 10 mL/kg of normal saline. On our arrival, his clinical examination was as follows: he was awake and alert with an oxygen saturation of 98% on 10 L of oxygen by face mask. He had a sunken anterior fontanel, but his capillary refill was 2 seconds with good skin turgor and strong peripheral pulses. The only clinical abnormality was bradycardia with heart rates ranging from 84 to 100. The patient’s mother was at the bedside and said the infant had had no prob lems feeding, no diarrhea, but only one to two wet diapers per day. On the day of transport, she had taken him to the pediatrician, who had assessed that the boy had lost more than 2 pounds since birth and then referred him to the emergency department. After consulting with our medical control physician, the infant was given fluids of D5.9NS at a maintenance rate. It was decided not to give a fluid bolus because of the clinical examination consistent with normal intravascular volume status despite metabolic acidosis. The infant then was transported back to our facility during which time he remained stable. A few months later, our flight team transported a 2’/Z-year-old boy who weighed 11 kg and had hypernatremia. This child presented with an unsteady gait and lethargy and had a serum sodium level of 191 mEq/L. An arterial blood gas analysis was as follows: pH = 7.44, pOa = 89 tori-, pCOz = 43 torr, HCO, = 28 mEq/L, and BE = +4. An IV line was started, and he was given 30 mL/kg of normal saline as a bolus. On arrival, the flight crew found the patient to be awake, alert, and acting appropriately for his age. His capillary refill was less than 2 seconds; his skin was pink, warm, and dry; and he had strong peripheral pulses. However, he