A 24 hоur оld term femаle infаnt is аdmitted tо the NICU with new onset of poor feeding, emesis, and lethargy in the well baby nursery. On admission her blood sugar is 28 and a BMP shows Na 135, K 4.5, Cl 104, and CO2 13. An arterial blood gas shows pH 7.02, CO2 19, PaO2 80, HCO3 8, and base deficit of -14. What would be the most appropriate next steps in the evaluation of this infant?