Topic
Anion gap
About: Anion gap is a research topic. Over the lifetime, 1201 publications have been published within this topic receiving 23224 citations. The topic is also known as: AG & serum anion gap.
Papers published on a yearly basis
Papers
TL;DR: Two commonly used diagnostic approaches are compared, one relying on plasma bicarbonate concentration and "anion gap," the other on "base excess," with a third method based on physicochemical principles, for their value in detecting complex metabolic acid-base disturbances.
Abstract: We compare two commonly used diagnostic approaches, one relying on plasma bicarbonate concentration and “anion gap,” the other on “base excess,” with a third method based on physicochemical principles, for their value in detecting complex metabolic acid‐base disturbances. We analyzed arterial blood samples from 152 patients and nine normal subjects for pH, P CO 2 , and concentrations of plasma electrolytes and proteins. Ninety-six percent of the patients had serum albumin concentration < 3 SD below the mean of the control subjects. In about one-sixth of the patients, base excess and plasma bicarbonate were normal. In a great majority of these apparently normal samples, the third method detected simultaneous presence of acidifying and alkalinizing disturbances, many of them grave. The almost ubiquitous hypoalbuminemia confounded the interpretation of acid‐base data when the customary approaches were applied. Base excess missed serious acid‐base abnormalities in about one-sixth of the patients; this method fails when the plasma concentrations of the nonbicarbonate buffers (mainly albumin) are abnormal. Anion gap detected a hidden “gap acidosis” in only 31% of those samples with normal plasma bicarbonate in which such acidosis was diagnosed by the third method; when adjusted for hypoalbuminemia, it reliably detected the hidden abnormal anions. The proposed third method identifies and quantifies individual components of complex acid‐base abnormalities and provides insights in their pathogenesis.
490 citations
TL;DR: Adverse effects of acute metabolic acidosis primarily include decreased cardiac output, arterial dilatation with hypotension, altered oxygen delivery, decreased ATP production, predisposition to arrhythmias, and impairment of the immune response.
Abstract: ) - ((HCO 3 - ) + (Cl - )), aids diagnosis by classifying the disorders into categories of normal (hyperchloremic) anion gap or elevated anion gap. These categories can overlap, however. Adverse effects of acute metabolic acidosis primarily include decreased cardiac output, arterial dilatation with hypotension, altered oxygen delivery, decreased ATP production, predisposition to arrhythmias, and impairment of the immune response. The main adverse effects of chronic metabolic acidosis are increased muscle degradation and abnormal bone metabolism. Using base to treat acute metabolic acidosis is controversial because of a lack of definitive benefit and because of potential complications. By contrast, the administration of base for the treatment of chronic metabolic acidosis is associated with improved cellular function and few complications.
440 citations
TL;DR: It is important for the clinician to have a high degree of suspicion for these disorders in cases of high anion gap metabolic acidosis, acute renal failure, or unexplained neurologic disease so that treatment can be initiated early.
Abstract: Alcohol-related intoxications, including methanol, ethylene glycol, diethylene glycol, and propylene glycol, and alcoholic ketoacidosis can present with a high anion gap metabolic acidosis and increased serum osmolal gap, whereas isopropanol intoxication presents with hyperosmolality alone. The effects of these substances, except for isopropanol and possibly alcoholic ketoacidosis, are due to their metabolites, which can cause metabolic acidosis and cellular dysfunction. Accumulation of the alcohols in the blood can cause an increment in the osmolality, and accumulation of their metabolites can cause an increase in the anion gap and a decrease in serum bicarbonate concentration. The presence of both laboratory abnormalities concurrently is an important diagnostic clue, although either can be absent, depending on the time after exposure when blood is sampled. In addition to metabolic acidosis, acute renal failure and neurologic disease can occur in some of the intoxications. Dialysis to remove the unmetabolized alcohol and possibly the organic acid anion can be helpful in treatment of several of the alcohol-related intoxications. Administration of fomepizole or ethanol to inhibit alcohol dehydrogenase, a critical enzyme in metabolism of the alcohols, is beneficial in treatment of ethylene glycol and methanol intoxication and possibly diethylene glycol and propylene glycol intoxication. Given the potentially high morbidity and mortality of these intoxications, it is important for the clinician to have a high degree of suspicion for these disorders in cases of high anion gap metabolic acidosis, acute renal failure, or unexplained neurologic disease so that treatment can be initiated early.
413 citations
TL;DR: Calculation of the serum anion gap remains an inexpensive and effective tool that aids detection of various acid-base disorders, hematologic malignancies, and intoxications.
Abstract: The serum anion gap, calculated from the electrolytes measured in the chemical laboratory, is defined as the sum of serum chloride and bicarbonate concentrations subtracted from the serum sodium concentration. This entity is used in the detection and analysis of acid-base disorders, assessment of quality control in the chemical laboratory, and detection of such disorders as multiple myeloma, bromide intoxication, and lithium intoxication. The normal value can vary widely, reflecting both differences in the methods that are used to measure its constituents and substantial interindividual variability. Low values most commonly indicate laboratory error or hypoalbuminemia but can denote the presence of a paraproteinemia or intoxication with lithium, bromide, or iodide. Elevated values most commonly indicate metabolic acidosis but can reflect laboratory error, metabolic alkalosis, hyperphosphatemia, or paraproteinemia. Metabolic acidosis can be divided into high anion and normal anion gap varieties, which can be present alone or concurrently. A presumed 1:1 stoichiometry between change in the serum anion gap (DeltaAG) and change in the serum bicarbonate concentration (DeltaHCO(3)(-)) has been used to uncover the concurrence of mixed metabolic acid-base disorders in patients with high anion gap acidosis. However, recent studies indicate variability in the DeltaAG/DeltaHCO(3)(-) in this disorder. This observation undercuts the ability to use this ratio alone to detect complex acid-base disorders, thus emphasizing the need to consider additional information to obtain the appropriate diagnosis. Despite these caveats, calculation of the serum anion gap remains an inexpensive and effective tool that aids detection of various acid-base disorders, hematologic malignancies, and intoxications.
401 citations
TL;DR: It is shown how hypoalbuminemia lowers the anion gap, which can mask a significant gap acidosis; and to derive a correction factor for it, which is adjusted for the effect of abnormal serum albumin concentrations.
Abstract: ObjectivesTo show how hypoalbuminemia lowers the anion gap, which can mask a significant gap acidosis; and to derive a correction factor for it.DesignObservational study.SettingIntensive care unit in a university-affiliated hospital.SubjectsNine normal subjects and 152 critically ill patients (265 m
383 citations
Related Topics (5)
Performance Metrics
| Year | Papers |
|---|---|
| 2025 | 17 |
| 2024 | 38 |
| 2023 | 79 |
| 2022 | 108 |
| 2021 | 57 |
| 2020 | 55 |