Bicarbonate levels are clinically useful to:
- To detect, evaluate, and monitor electrolyte imbalances in the body due to
- Endocrine disease
- Evaluation of acidosis or alkalosis
- Renal disease
- Lung disorders
- Metabolic disorders
- Sepsis
- To evaluate and monitor acid-base balance in the body due to
- Decreased venous CO2
- Increased venous CO2
Additional information:
- Often measured along with the test for arterial blood gases (ABG)
- Bicarbonate levels are increased in metabolic alkalosis and compensated respiratory acidosis. They are decreased in metabolic acidosis and compensated respiratory alkalosis
- In normal individuals there is a 30% day to day variation
- It is highest in spring and lowest in summer
- In women, it is lowest during the menstrual periods
Consult your laboratory for their normal ranges as these may vary somewhat from the ones listed below.
| Conv. units
(mEq/L) | SI units
(mmol/L) |
|---|
| Adult: | 22-30 | 22-30 |
| Child/Infant: | 20-28 | 20-28 |
| Critcal Values | | <15 |
| | >40 |
Erroneous results may result from:
- A delay in analysis (Lowers bicarbonate concentration)
- Exposure to air (Reduces CO2 levels)
- Specimen not maintained at low temperature (Glycolysis & production of lactic acid will result in a fall in pH & rise in PCO2)
Conditions associated with elevated bicarbonate levels include:
- GI loss of acids
- NG suctioning
- Vomiting (Severe)
- Respiratory disorders
- Airway obstruction
- Asthma (w/ Resp. Acidosis)
- COPD (w/ Resp. Acidosis)
- Hypoventilation/Respiratory center depression
- Pneumonia or other pulmonary infections
- Acute intermittent Porphyria
- Aldosteronism (Primary)
- Brain tumor
- Conn's syndrome
- Cushing's syndrome
- Metabolic alkalosis
- Respiratory acidosis
- Cardiac disorders
- Hypothyroidism
- Myopathy
- Poliomyelitis
- Drugs
- Acetylsalicylic acid
- Aldosterone
- Amphotericin B
- Anesthetics
- Antacids
- Bicarbonate
- Calcium carbonate
- Carbenicillin
- Carbenoxolone
- Corticosteroids
- Dexamethasone
- Diuretics (Loop)
- Glycyrrhiza
- Laxatives (chronic abuse)
- Mafenide
- Metolazone
- Opiates/Sedatives
- Volume depleting agents
- X-ray contrast agents
Conditions associated with decreased bicarbonate levels include:
- Anxiety (due to compensation for respiratory alkalosis with hyperventilation)
- Burns
- Dehydration
- Diabetic ketoacidosis
- Diarrhea (Severe)
- Fever (High)
- Hyperthyroidism
- Metabolic acidosis
- Renal failure
- Respiratory alkalosis (Compensation for)
- Shock
- Starvation (Ketosis)
- Drugs
- 2,4-dinitrophenol intoxication
- Acetazolamide
- Aldosterone antagonists
- Amiloride
- Ammonium chloride
- Aspirin/Salicylate ingestion
- Capreomycin
- Citrates
- Dimercaprol
- Dimethadione
- Diuretics (Thiazides)
- Ether
- Ethylene glycol
- Fluorides
- Gentamicin
- Heroin withdrawal
- Metformin
- Methicillin
- Methyl alcohol
- Nitrofurantoin
- Paraldehyde
- Streptomycin
- Tetracycline
- Triamterene
- Xylitol