What is the compensation for metabolic acidosis?
Professionals
| Disorder | Expected compensation | Correction factor |
|---|---|---|
| Metabolic acidosis | PaCO2 = (1.5 x [HCO3-]) +8 | ± 2 |
| Acute respiratory acidosis | Increase in [HCO3-]= ∆ PaCO2/10 | ± 3 |
| Chronic respiratory acidosis (3-5 days) | Increase in [HCO3-]= 3.5(∆ PaCO2/10) | |
| Metabolic alkalosis | Increase in PaCO2 = 40 + 0.6(∆HCO3-) |
What does the Davenport diagram show?
Davenport diagrams are graphic displays of acid-base states. They illustrate the dynamic relationships between arterial blood pH, bicarbonate and non-bicarbonate buffers, and the partial pressure of carbon dioxide.
How do you know if metabolic acidosis is compensated?
Assume metabolic cause when respiratory is ruled out. If PaCO2 is abnormal and pH is normal, it indicates compensation. pH > 7.4 would be a compensated alkalosis. pH < 7.4 would be a compensated acidosis.
How does metabolic compensation work?
Metabolic compensation (alkalosis): The body compensates for the decreased pH from the primary respiratory acidosis by increasing renal excretion of H+.
How long does it take for metabolic compensation?
Metabolic compensation for a respiratory alkalosis develops gradually and takes 2-3 days. In chronic compensation, plasma bicarbonate falls by 4 for each 10 mm Hg decrease in the Pco2.
What is normal PCO2?
between 35 to 45 mmHg
The partial pressure of carbon dioxide (PCO2) is the measure of carbon dioxide within arterial or venous blood. It often serves as a marker of sufficient alveolar ventilation within the lungs. Generally, under normal physiologic conditions, the value of PCO2 ranges between 35 to 45 mmHg, or 4.7 to 6.0 kPa.
What is physiological acid-base balance?
To maintain homeostasis, the human body employs many physiological adaptations. One of these is maintaining an acid-base balance. In the absence of pathological states, the pH of the human body ranges between 7.35 to 7.45, with the average at 7.40. A pH below 7.35 is an acidemia, and a pH above 7.45 is an alkalemia.
How do you determine compensated ABG?
If the pH is not within or close to the normal ranges, then a partial-compensation exists. If the pH is back within normal ranges then a full-compensation has occurred. A non-compensated or uncompensated abnormality usually represents an acute change occurring in the body.
How long does metabolic compensation take?
How is the Davenport diagram used in the clinical setting?
Although the surface represented in the diagram is experimentally determined, the Davenport diagram is rarely used in the clinical setting, but allows the investigator to envision the effects of physiological changes on blood acid-base chemistry.
Who is the creator of the Davenport diagram?
Davenport diagram In acid base physiology, the Davenport Diagram is a graphical tool, developed by Horace Davenport, that allows a clinician or investigator to describe blood bicarbonate concentrations and blood pH following a respiratory and/or metabolic acid-base disturbance.
Why are titration curves called isopleths in the Davenport diagram?
In the Davenport Diagram, these titration curves are called isopleths, because they are generated at a fixed partial pressure of carbon dioxide.
What are the red lines in the Davenport diagram?
In Fig. 10, the dark red lines are the actual buffer lines in three-dimensional space, while the light red lines are the projections of the buffer lines onto a two-dimensional plane. (We will see later how multiple, parallel buffer lines can be determined for a given system).