Case 1: Lactic Acidosis and Respiratory Distress in a 10-Day-Old Infant

A previously healthy male infant born at 39 weeks’ gestation to a 33-year-old, gravida 1 para 1 mother presents to an outside hospital with respiratory distress at age 10 days. The infant was delivered via cesarean delivery for failure to progress, with Apgar scores of 8 and 9 at 1 minute and 5 minutes, respectively. His nursery stay was uneventful, and he was discharged home on day 2 after birth. During the next several days, he developed feeding difficulty and increased workof breathing. At the outside hospital emergency department, rectal temperature is 98.8°F (37.1°C), heart rate is 170 beats per minute, blood pressure is 105/74 mm Hg, respiratory rate is 78 breaths per minute, and oxygen saturation is 84% on room air. Reported physical examination findings are otherwise unremarkable. Continuous positive airway pressurewith pressure support breaths is initiated. Electrocardiography reveals sinus tachycardia. Initial laboratory evaluation reveals the following: pH 6.8; bicarbonate, 7 mEq/L (7 mmol/L); base deficit, −27 mEq/L (−27 mmol/L); lactate, 153 mg/dL (17 mmol/L); anion gap, 29 mEq/L (29 mmol/L); white blood cell count, 27,000/μL (27.0 × 109/L), with normal differential; hematocrit, 57% (0.57); C-reactive protein, 1.0 mg/L (9.5 nmol/L); and glucose, 39 mg/dL (2.2 mmol/L). The patient is intubated. Chest radiography is performed (Fig 1). Dextrose, normal saline, bicarbonate, and broad-spectrum antibiotics are given for presumed sepsis, and the patient transfers to our neonatal intensive care unit for further evaluation and management. Figure 1. Chest radiograph of the …