From the Guidelines
To fix gap acidosis, first identify and treat the underlying cause, and according to the most recent evidence 1, management goals include restoration of circulatory volume and tissue perfusion, resolution of ketoacidosis, and correction of electrolyte imbalance and acidosis. The treatment approach varies depending on the underlying cause of gap acidosis.
- For diabetic ketoacidosis (DKA), administer IV insulin at 0.1 units/kg/hour after an initial bolus of 0.1 units/kg, along with IV fluids (normal saline at 15-20 mL/kg in the first hour) 1.
- Monitor glucose levels hourly and add dextrose when glucose falls below 250 mg/dL.
- For alcoholic ketoacidosis, provide IV fluids, glucose, and thiamine 100 mg IV.
- For lactic acidosis, focus on improving tissue perfusion with fluids and treating the underlying condition (sepsis, shock).
- For toxic ingestions like methanol or ethylene glycol, administer fomepizole (15 mg/kg loading dose, then 10 mg/kg every 12 hours) or ethanol infusion, and consider hemodialysis 1. Some key points to consider:
- Sodium bicarbonate therapy (1-2 mEq/kg IV) may be used temporarily for severe acidosis (pH < 7.1) but doesn't address the underlying problem.
- Gap acidosis occurs when acids accumulate in the bloodstream, increasing the anion gap (normally 8-12 mEq/L).
- Successful treatment requires addressing the specific cause rather than just correcting the pH, as the acidosis will resolve once the excess acid production stops or the toxins are cleared. It's essential to note that the use of bicarbonate in patients with DKA made no difference in the resolution of acidosis or time to discharge, and its use is generally not recommended 1. The most recent and highest quality study 1 provides the best guidance for managing gap acidosis, and its recommendations should be prioritized in clinical practice.
From the FDA Drug Label
Treatment consists of blocking the formation of toxic metabolites using inhibitors of alcohol dehydrogenase, such as fomepizole injection, and correction of metabolic abnormalities In addition to specific antidote treatment with fomepizole, patients intoxicated with ethylene glycol or methanol must be managed for metabolic acidosis, acute renal failure (ethylene glycol), adult respiratory distress syndrome, visual disturbances (methanol), and hypocalcemia. Fluid therapy and sodium bicarbonate administration are potential supportive therapies In addition, potassium and calcium supplementation and oxygen administration are usually necessary.
To fix gap acidosis, treatment should include:
- Blocking toxic metabolite formation using inhibitors like fomepizole injection
- Correction of metabolic abnormalities
- Management of metabolic acidosis with:
- Fluid therapy
- Sodium bicarbonate administration
- Potassium supplementation
- Calcium supplementation
- Oxygen administration Hemodialysis should be considered in cases of renal failure, significant or worsening metabolic acidosis, or high ethylene glycol or methanol concentrations 2.
From the Research
Understanding Gap Acidosis
Gap acidosis, also known as anion gap metabolic acidosis, occurs when there is an increase in the anion gap due to unmeasured anions in the blood. This condition can be caused by various factors, including diabetic ketoacidosis (DKA), lactic acidosis, and other metabolic disorders.
Causes of Gap Acidosis
- Diabetic ketoacidosis (DKA) is a common cause of gap acidosis, characterized by hyperglycemia, metabolic acidosis, and ketosis 3, 4, 5.
- Lactic acidosis is another cause of gap acidosis, which can occur in combination with DKA or as a separate entity 6, 7.
- Other metabolic disorders, such as renal failure or poison intake, can also lead to gap acidosis 6.
Management of Gap Acidosis
- Restoration of circulating volume, insulin therapy, electrolyte replacement, and treatment of underlying precipitating events are essential in managing DKA and gap acidosis 3, 4.
- Identifying and treating the underlying cause of lactic acidosis is crucial in managing gap acidosis 6, 7.
- Frequent monitoring of the patient's clinical and laboratory states is necessary to ensure proper management of gap acidosis 4.
- Discharge plans should include patient education on adherence to insulin and self-care guidelines to prevent recurrence of DKA and gap acidosis 4.