==ANION GAP ACIDOSIS==

see also [[3.2.1.1.1 Acidosis Teaching Resources|Acidosis Teaching Resources]]

The anion gap (in mmol/L) = (Na+ K) - (HCO3 + Cl)
An anion gap of 7 - 17 mmol/L is normal.

An anion gap > 17 mmol/L, in the presence of acidosis suggests
* lactic acidosis - may be secondary to [[3.2.1.1.6 Hypotension and Bradycardia|shock]] or [[3.4.2 Control of Seizures Anticonvulsants|seizures]] from a number of poisons
* diabetic, alcoholic or starvation ketoacidosis
* renal failure (GFR < 10% of normal)
* infantile organic acidosis

or poisoning with one of the following toxins that alter metabolism leading to acidosis
* Benzyl alcohol
* Beta-adrenergic agents
* Caffeine
* [[2.2.9.1.1 Carbon monoxide|Carbon monoxide]]
* [[2.2.9.1.2 Cyanide|Cyanide]]
* [[2.1.11.5.1 Acute Management of Alcohol Problems|Ethanol]]
* [[2.2.5.2.2 Ethylene glycol|Ethylene glycol]]
* Hydrogen sulfide
* [[2.1.1.2 Nonsteroidal Anti-inflammatory Drugs|Ibuprofen]]
* [[2.1.9.6 Iron|Iron]]
* Isoniazid (INH)
* [[2.1.11.9.4 Mood stabilizers|Lithium]]
* [[2.1.7.1.3.1 Biguanides|Metformin]]
* [[2.2.5.2.5 Methanol|Methanol]]
* [[2.1.1.1 Acetaminophen|Paracetamol]]
* Paraldehyde
* [[2.1.7.1.3.1 Biguanides|Phenformin]]
* [[2.1.1.4 Salicylates|Salicylates]]
* Strychnine
* [[3.2.1.3 Toxidromes|Sympathomimetic amines]]
* Toluene