A patient presents with fruity breath, abdominal pain, and high blood glucose. What is the most appropriate immediate management?

The presentation of fruity breath, abdominal pain, and high blood glucose is indicative of diabetic ketoacidosis (DKA). In DKA, the accumulation of ketones in the blood leads to metabolic acidosis, severe dehydration, and an elevated blood glucose level.

The most appropriate immediate management involves addressing the underlying causes and complications of DKA. This includes administering intravenous fluids to rehydrate the patient, correct electrolyte imbalances, and provide insulin therapy to lower blood glucose levels. Starting with intravenous fluids helps to rehydrate the patient and improve renal perfusion, which is critical in facilitating glucose and ketone clearance. After initial fluid resuscitation, insulin is introduced to inhibit ketogenesis and lower blood glucose levels.

This combination not only addresses the high glucose levels but also helps to correct the metabolic acidosis by promoting utilization of glucose and preventing further fat breakdown, which is responsible for ketone production. Therefore, intravenous fluids followed by insulin is the most appropriate immediate management for a patient in this state.