A acidosis (obsolete also acidosis , from latin acidum "acid") is a disorder of acid-base balance in humans and animals, the lowering of the pH caused in the blood (or other bodily liquids). If the pH value in the blood is below 7.35, it is called acidosis. The reference range in humans is 7.35 to 7.45. If it is higher, one speaks of an alkalosis .
- In respiratory acidosis, there is insufficient exhalation of carbon dioxide .
- In metabolic acidosis there is an accumulation of too much acidic metabolic products in the blood, such as B. in derailed sugar disease or chronic kidney disease. The pH value drops when the buffer capacity of the blood buffer (see acid-base balance ) against acids is exhausted. This leads to a sudden sharp drop in the pH value and acute over-acidification occurs. This is often an acutely life-threatening phenomenon.
- Anaerobic glycolysis (e.g. due to a lack of oxygen ) and the increased formation of ketone bodies ( due to a lack of insulin ) lead to an increase in the concentration of acidic metabolic products ( lactate , ketone bodies) in the tissue and thus to tissue acidosis . She will u. a. observed in shock , cardiac arrest , diabetic coma and severe circulatory disorders , temporarily and without disease value also in the muscles after maximum anaerobic physical exertion.
Acidosis represents a respiratory stimulus. Deep breathing ( Kussmaul breathing ) can partially compensate for a non-respiratory acidosis, such as can occur in kidney failure. The compensatory release of hydrogen carbonate by the cells is combined with a release of potassium , which leads to hyperkalemia .
Acidosis inhibits glycolysis and promotes the breakdown of glucose via the pentose phosphate pathway . Acidosis has a negative dromotropic effect on the heart (slower spread of excitation due to the closure of gap junctions ) and negative inotropic (reduced cardiac strength by reducing the likelihood of calcium channels opening ), which together with the vasodilatation caused by the low pH value can result in a drop in blood pressure .
The acidosis is detected by a blood gas analysis . Based on the measurement values of bicarbonate and carbon dioxide - partial pressure in the arterial blood can be distinguished between a respiratory and metabolic disorder. Respiratory acidosis can be recognized by an increased CO 2 partial pressure (PCO 2 ), in metabolic acidosis the standard bicarbonate concentration is lower.
In the case of acidosis, the cause must be eliminated if possible. If the pH value drops below 7.1, a correction can be made with bicarbonate.
- More about acidosis
- Disorders of the acid-base balance: Rational diagnostics and economic therapy. Dtsch Arztebl 2005; 102: A 1896-1899 (issue 26)
- Richard Daikeler, idols Use, Sylke Waibel: diabetes. Evidence-based diagnosis and therapy. 10th edition. Kitteltaschenbuch, Sinsheim 2015, ISBN 978-3-00-050903-2 , p. 110.