---
title: Diabetic Ketoacidosis Protocol
description: A comprehensive clinical reference for the diagnosis and management of diabetic ketoacidosis.
keywords: [diabetic ketoacidosis, DKA, hyperglycemia, insulin, fluid resuscitation]
category: clinical
---

## Definition and Diagnostic Criteria

Diabetic ketoacidosis (DKA) is an acute, life-threatening complication of diabetes mellitus characterized by the triad of hyperglycemia, metabolic acidosis, and increased ketone bodies. The diagnostic criteria for DKA include:

- Plasma glucose level > 250 mg/dL (13.9 mmol/L)
- Arterial pH < 7.30 
- Serum bicarbonate level < 18 mEq/L (18 mmol/L)
- Presence of ketones in the blood or urine

DKA typically occurs in patients with type 1 diabetes, but can also develop in those with type 2 diabetes, especially in the setting of acute illness or infection.

## Pathophysiology

The development of DKA is driven by an absolute or relative insulin deficiency, which leads to increased glucagon secretion and activation of catabolic pathways. This results in increased hepatic glucose production, decreased peripheral glucose utilization, and excessive ketone body formation from the breakdown of fatty acids.

The metabolic derangements in DKA include:

- Hyperglycemia: Excessive hepatic glucose production and impaired peripheral glucose uptake
- Metabolic acidosis: Accumulation of ketone bodies (β-hydroxybutyrate and acetoacetate) 
- Dehydration: Osmotic diuresis and fluid/electrolyte losses

## Initial Evaluation and Diagnostic Testing

The initial evaluation of a patient with suspected DKA should include the following:

- History and physical exam: Assess for precipitating factors (e.g. infection, medication non-adherence)
- Laboratory tests:
  - Serum glucose, electrolytes (sodium, potassium, chloride, bicarbonate), BUN, creatinine
  - Arterial or venous blood gas to determine pH, PCO2, and bicarbonate
  - Serum and/or urine ketones
  - Complete blood count, lactate, phosphate, magnesium
- Electrocardiogram to evaluate for cardiac complications

## Treatment Principles

The goals of DKA treatment are to:

1. Correct fluid and electrolyte deficits
2. Suppress ketone production through insulin administration
3. Treat the underlying precipitating cause

### Fluid Resuscitation
- Initial fluid bolus of 1-2 L of normal saline (0.9% NaCl) over the first 1-2 hours
- Subsequent fluid rate of 250-500 mL/hour, adjusting based on clinical status and electrolyte levels

### Insulin Therapy
- Regular (short-acting) insulin: Continuous intravenous (IV) infusion at 0.1 units/kg/hour
- Transition to subcutaneous insulin when blood glucose < 200 mg/dL (11.1 mmol/L) and acidosis is resolved

### Electrolyte Management
- Potassium replacement:
  - If K+ < 3.3 mEq/L (3.3 mmol/L), hold insulin and give 20-30 mEq/L of potassium in fluids
  - If K+ 3.3-5.0 mEq/L (3.3-5.0 mmol/L), add 10-20 mEq/L of potassium to fluids
- Phosphate and magnesium replacement as needed

### Monitoring
- Frequent monitoring of vital signs, fluid intake/output, and laboratory tests (every 2-4 hours)
- Continuous cardiac monitoring for arrhythmias
- Close monitoring for cerebral edema, which can be a life-threatening complication

## Treatment Algorithm

1. Initiate fluid resuscitation with normal saline
2. Start continuous IV insulin infusion at 0.1 units/kg/hour
3. Monitor electrolytes and replace potassium, phosphate, and magnesium as needed
4. Reassess patient every 2-4 hours and adjust treatment accordingly
5. Transition to subcutaneous insulin when blood glucose < 200 mg/dL (11.1 mmol/L) and acidosis is resolved

## Complications and Contraindications

### Complications
- Cerebral edema: More common in children, can be life-threatening
- Hypokalemia or hyperkalemia
- Hypophosphatemia
- Hypoglycemia
- Acute kidney injury

### Contraindications
- Severe dehydration or hemodynamic instability requiring immediate fluid resuscitation
- Suspicion of acute coronary syndrome or stroke, which may require different management priorities

## Conclusion

Diabetic ketoacidosis is a medical emergency that requires prompt recognition and management. The key principles of DKA treatment include fluid resuscitation, insulin administration, and electrolyte replacement, with close monitoring for complications. Adherence to established clinical guidelines and protocols is essential for optimizing patient outcomes.