Diabetic ketoacidosis (DKA) is a complication of diabetes arising from a shortage of insulin in the body. This medical emergency requires immediate intervention and typically develops over hours or days. DKA most commonly affects people with type 1 diabetes, but it can occur in those with type 2 diabetes. When the body lacks sufficient insulin, it cannot effectively use glucose for energy, triggering metabolic events that result in the buildup of harmful acidic substances.
The Metabolic Mechanism Behind Diabetic Ketoacidosis
The root of DKA is the body’s inability to utilize glucose, the primary fuel source, due to insufficient insulin. Insulin normally allows glucose to enter the body’s cells for energy production. Without insulin, glucose accumulates in the bloodstream, leading to high blood sugar (hyperglycemia), while cells starve for fuel.
To compensate, the body shifts its metabolism, increasing the release of counter-regulatory hormones like glucagon, cortisol, and epinephrine. These hormones enhance the breakdown of fat stores (lipolysis) to provide an alternative energy source.
These free fatty acids travel to the liver, where they are metabolized to generate energy. This fat metabolism results in the overproduction of acidic compounds called ketone bodies, primarily beta-hydroxybutyrate and acetoacetate. The accumulation of these ketones overwhelms the body’s natural buffering systems, driving the blood pH down and creating metabolic acidosis. The high concentration of glucose and ketones in the blood draws water out of the body’s cells, leading to dehydration.
Primary Triggers and Causes
The immediate cause of DKA is typically provoked by an underlying event or factor. One of the most common triggers is the omission or inadequacy of prescribed insulin doses. This can result from forgetting to take a dose, administering too little insulin, or equipment failure, such as a malfunctioning insulin pump.
Acute illness or infection represents another common cause of DKA episodes. Infections like pneumonia, influenza, or a urinary tract infection cause the body to release high levels of stress hormones. These hormones oppose the action of insulin, increasing insulin resistance and accelerating the metabolic shift toward fat breakdown.
For many people, DKA serves as the first sign that they have type 1 diabetes. In these instances, the immune system has destroyed enough insulin-producing cells that the body can no longer generate the hormone needed. Other triggers include physical trauma, a heart attack, stroke, or the use of certain medications like corticosteroids and some diuretics.
Recognizing the Warning Signs
The symptoms of DKA can develop quickly, especially in children or if vomiting is involved. Early warning signs are often related to high blood glucose levels and include polyuria (frequent urination) and excessive thirst. This increased urination is the body’s attempt to flush out excess sugar and ketones, which leads to dehydration.
As the condition worsens, symptoms reflect the accumulating acidosis and dehydration. A person may experience nausea, vomiting, and abdominal pain. They often feel weakness and fatigue, and their skin and mouth become dry.
A hallmark sign of DKA is Kussmaul respirations, characterized by fast, deep breaths. This pattern is the body’s attempt to expel carbon dioxide to raise the blood pH. Excess ketones, particularly acetone, are exhaled, giving the breath a sweet or “fruity” odor. If left untreated, the buildup of acids and dehydration can lead to confusion, decreased alertness, and eventually, loss of consciousness.
Emergency Response and Treatment
DKA requires immediate professional care, typically in a hospital setting. Treatment focuses on three goals: restoring fluid balance, correcting acidosis, and replacing lost electrolytes. Prompt administration of intravenous fluids, usually a saline solution, is the first step to correct dehydration and help dilute the excess glucose in the blood.
Insulin therapy is then initiated via an intravenous drip. This insulin infusion halts the production of ketones by suppressing lipolysis and allows the body’s cells to begin using glucose for energy. The insulin is carefully titrated to safely and steadily reverse the ketoacidosis.
Electrolyte replacement is important, particularly for potassium. Even if initial blood tests show normal potassium levels, insulin administration causes potassium to rapidly move from the bloodstream into the cells, leading to a drop in serum levels. Healthcare teams monitor blood chemistry closely and administer replacement electrolytes to ensure proper function of the heart, muscles, and nerve cells. Treatment also includes addressing the underlying trigger, such as administering antibiotics for an infection.
Reducing the Risk of DKA
Preventing DKA centers on diabetes self-management and preparedness, especially during illness. A person with diabetes should adhere to their prescribed insulin regimen and never skip doses, even when feeling unwell or having a reduced appetite. Consistent blood sugar monitoring is necessary, with more frequent checks required when glucose levels are elevated or during periods of stress.
Regular testing for ketones allows for early intervention before DKA becomes severe. This is important when blood sugar is high (often above 250 mg/dL) or if symptoms like nausea and vomiting are present. Ketone testing can be done at home using urine strips or a blood ketone meter.
Working with a healthcare provider to establish a “sick-day management” plan is recommended. This plan should outline when to check ketones, how to adjust insulin and fluid intake during illness, and the ketone levels that necessitate seeking emergency care. Maintaining adequate hydration, especially with non-sugary fluids, helps the body flush out excess glucose and ketones and mitigate the risk of DKA.