Bicarbonate | Laboratory research

Acid-base equilibrium (CBS) is the ratio of the concentration of hydrogen and hydroxyl ions in the biological environment. The regulatory systems that directly ensure the maintenance of blood pH are the buffer and physiological systems of the blood and tissues (lungs, kidneys, liver, and gastrointestinal tract).

2-80% of the total CO90 is represented as bicarbonate ion (HCO3 -), which is involved in maintaining the pH constant.

Bicarbonate is the second largest plasma anionic fraction, so its concentration is an important indicator of electrolyte distribution and anionic deficiency. In addition to determining blood pH, the determination of bicarbonate concentration is useful for the diagnostics and treatment of many diseases that are accompanied by acid-base imbalance due to respiratory or metabolic causes.

Most often, abnormal levels of HCO3 indicate a metabolic rather than a respiratory disorder; Thus, a decrease in HCO3 indicates metabolic acidosis (e.g., diabetes with ketoacidosis), while an increase in HCO3 indicates metabolic alkalosis (developed, for example, as a result of prolonged vomiting).

When should we test for bicarbonate?

In cases of acid-base imbalance (used to determine blood pH).

How to prepare for the test?

Fasting is recommended for the test.

Research material

Venous blood

Possible interpretation of the results

Bicarbonate concentration increases:

1. Metabolic alkalosis

• Prolonged vomiting;
• Gastric aspiration;
• Colonic adenoma;
• Hyperaldosteronism;
• Treatment with diuretics;
• Chronic diarrhea;
• Taking antacids.

2. Respiratory acidosis

• Respiratory depression: trauma, infections, medications.
• Neuromuscular disorders: poliomyelitis, myopathy, Guillain-Barré syndrome;
• Cardiopulmonary disorders: hydrothorax, pneumothorax, COPD, pulmonary edema, asthma.

3. Respiratory acidosis with metabolic alkalosis

Bicarbonate concentration decreases:

1. Metabolic acidosis

• Renal failure;
• Renal tubular acidosis;
• Ketoacidosis: diabetes, starvation, alcoholism;
• Lactate acidosis;
• Poisoning with salicylates;
• Obstructive nephropathy.
• Urethrosigmoidostomy;
• Severe diarrhea;
• Deficiency of mineralocorticoids.

2. Respiratory alkalosis

• Anxiety, hysteria;
• Pregnancy;
• CNS disorders: hypoxemia, infections, trauma, hepatic encephalopathy.

3. Metabolic acidosis with respiratory alkalosis

Resources

https://www.synevo.ro/shop/bicarbonat-eco2/
https://spravochnik.synevo.ua/ru/klinicheskaia-himia/bicarbonates.html