Diagnosis | Respiratory acidosis

Diagnosis

The diagnosis of respiratory acidosis is made by means of blood gas analysis of the arterial blood. This means that blood is not drawn from a vein as is normally the case, but from an artery. The blood is sent to the laboratory.

There, the pH value is determined as well as the exact pCO2, i.e. CO2 partial pressure. These values can then be used to determine whether acidosis is present and whether the reason is hypercapnia, i.e. too high a CO2 concentration in the blood. If the pH value is below 7.35 and the pCO2 is greater than 45 mmHg, then by definition respiratory acidosis is present. ” to learn more about the clinical picture.

BGA

Blood gas analysis measures certain parameters in the arterial blood so that a statement can be made about the acid-base balance and the electrolytes in the plasma. If isolated respiratory acidosis is present, the following values are outside the normal range: pH <7.35 pCO2 > 44mmHg. If the respiratory acidosis has been present for a longer time, a so-called metabolic compensation occurs.

This means that the other system, which regulates the acid-base balance, counteracts the derailment. Respiratory acidosis is a disorder of the respiratory system, i.e. the lungs. In order to counteract a complete metabolic derailment, the metabolic system, i.e. the kidney, intervenes in this case. In order to keep the pH as far as possible within the normal range, the kidney excretes less bicarbonate. Alkaline valencies are thus retained in the body to retain the acidic excess.This means that in case of chronic respiratory acidosis the BGA could be as follows: pH 7.34 pCO2 68.2 mmHg (instead of the normal 36-44 mmHg) pO2 61% (due to insufficient respiration the blood is insufficiently oxygenated) HCO3- 36.6 mmHg (normally between 22-26 mmHg) BE +8 (normally -/+2)

  • PH <7.35
  • PCO2 > 44mmHg.
  • PH 7.34
  • PCO2 68.2 mmHg (instead of 36-44 mmHg as normal)
  • PO2 61% (due to insufficient respiration the blood is insufficiently oxygenated)
  • HCO3- 36.6 mmHg (normally between 22-26 mmHg)
  • BE +8 (normally -/+2)

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All articles in this series:

  1. Respiratory acidosis
  2. Diagnosis
  3. What can be the long-term consequences of respiratory acidosis?
  4. Prognosis