Acidosis
In medicine, acidosis is an acid-based imbalance that is a "pathologic condition resulting from accumulation of acid or depletion of the alkaline reserve (bicarbonate) content of the blood and body tissues, and characterized by an increase in hydrogen ion concentration (decrease in pH). (Dorland, 27th ed)."[1][2]
- See also: Metabolic acidosis
Interactive calculators
In evaluating acidosis, there can be a number of calculations for which computer assistance is helpful. Listed below are several Web-based calculators. Specialists make extensive use of programmable calculators and personal digital assistant applications.
- Winter's formula (Expected pCO2 = 1.5 * HCO3 + 8 ± 2)
- Multiple anion gap calculations
- Anion Gap (without K): Na - (Cl + HCO3)
- Anion Gap (with K): (Na + K) - (Cl + HCO3)
- Delta Gap (without K): [Na - (Cl + HCO3)] - 12
Classification
Respiratory acidosis
In acute respiratory acidosis, for each increase in the PaCO2 of 10 mmHg, the pH decreases by 0.08.
Metabolic acidosis
"Metabolic acidoses are classified in terms of the anion gap."[3]
High anion gap
Examples include: Diabetic ketoacidosis
Low anion gap
"A decrease in the normal AG occurs in dilutional states, hypoalbuminemia, hypercalcemia, hypermagnesemia, hypernatremia, diseases associated with hyperviscosity, bromide intoxication, and in certain paraproteinemias."[4]
Also, surgery that created urinary diversion into the intestines (such as an ileal conduit) can cause hyperchloremic metabolic acidosis due to reabsorption of sodium.[5] This acidosis may be worse during worsening of renal failure.[6]
Mixed disorders
For each increase in the anion gap over 12 the bicarbonate should fall by the same amount. Thus Δ/Δ (Δ anion gap /Δ HCO3):[7]
- Δ/Δ < 1 suggests "that a mixed high AG and hyperchloraemic acidosis is present"
- Δ/Δ > 1 suggests "mixed metabolic alkalosis and metabolic acidosis is likely to be present"
References
- ↑ Anonymous (2024), Acidosis (English). Medical Subject Headings. U.S. National Library of Medicine.
- ↑ Narins RG, Gardner LB (March 1981). "Simple acid-base disturbances". Med. Clin. North Am. 65 (2): 321–46. PMID 7230961. [e]
- ↑ Narins RG, Jones ER, Stom MC, Rudnick MR, Bastl CP (March 1982). "Diagnostic strategies in disorders of fluid, electrolyte and acid-base homeostasis". Am. J. Med. 72 (3): 496–520. PMID 7036739. [e]
- ↑ Emmett M, Narins RG (January 1977). "Clinical use of the anion gap". Medicine (Baltimore) 56 (1): 38–54. PMID 401925. [e]
- ↑ Mundy AR (May 1999). "Metabolic complications of urinary diversion". Lancet 353 (9167): 1813–4. PMID 10359400. [e]
- ↑ Cruz DN, Huot SJ (May 1997). "Metabolic complications of urinary diversions: an overview". Am. J. Med. 102 (5): 477–84. DOI:10.1016/S0002-9343(97)00020-X. PMID 9217645. Research Blogging.
- ↑ Goodkin DA, Krishna GG, Narins RG (July 1984). "The role of the anion gap in detecting and managing mixed metabolic acid-base disorders". Clin Endocrinol Metab 13 (2): 333–49. DOI:10.1016/S0300-595X(84)80025-0. PMID 6488577. Research Blogging.