Do you know the clinical manifestations of metabolic acidosis?

Some people suddenly experience facial flushing, increased heart rate, low blood pressure, decreased muscle tone and other adverse symptoms for unknown reasons. These are the clinical manifestations of metabolic acidosis and must be treated in a timely manner, otherwise it will be life-threatening.

1. Clinical manifestations

The symptoms vary depending on the cause, and mild cases are often masked by the primary disease. The main symptoms are: a. Deep and rapid breathing, increased ventilation, decreased PCO2, which can reduce the decrease in pH, and sometimes there is a ketone smell in the exhaled breath; b. Facial flushing, accelerated heart rate, low blood pressure, confusion, and even coma. Patients often have symptoms of severe dehydration; c. Myocardial contractility and peripheral vascular sensitivity to catecholamines are reduced, causing arrhythmia and vasodilation, decreased blood pressure, acute renal failure and shock; d. Decreased muscle tone, decreased and disappeared tendon reflexes; e. Blood pH, carbon dioxide binding capacity (CO2CP), SB, BB, and BE are all reduced, and serum Cl- and K+ may increase. Urine tests generally show an acidic reaction.

2. Complications

1. Acidosis can reduce the binding of Ca2 to protein, thereby increasing the level of free Ca2. When correcting acidosis, sometimes free Ca2

The decrease in muscle strength causes tetany. A decrease in blood pH can inhibit renal 1α-hydroxylase and reduce the production of active vitamin D3. Chronic acidosis can lead to metabolic bone disease due to the long-term mobilization of calcium salts from the bones, which is quite common in patients with renal tubular acidosis.

2. Acidosis can increase protein decomposition, and chronic acidosis can cause malnutrition.

3. Metabolic acidosis combined with metabolic alkali poisoning? It can be seen in patients with renal failure who lose a large amount of acidic gastric acid due to frequent vomiting; patients with severe vomiting accompanied by severe diarrhea. At this time, metabolic factors cause pH, HCO3- and PaCO2 to move in opposite directions, so the final changes in these three indicators depend on which disorder is dominant, and they can be increased, decreased or within the normal range.

4. Acidosis is often accompanied by hyperkalemia. When alkali is given to correct acidosis, H+ moves from inside the cell to outside the cell and is continuously buffered, while K+ moves from outside the cell back into the cell, causing blood potassium to drop. However, it should be noted that some patients with metabolic acidosis have potassium loss, so although they have acidosis, they are also accompanied by hypokalemia. When the acidosis is corrected, the serum potassium concentration will further decrease, causing severe or even fatal hypokalemia. This situation is seen in diabetic patients who lose potassium due to osmotic diuresis and patients who lose potassium due to diarrhea. To correct acidosis, potassium supplementation should be appropriate based on the degree of serum potassium decrease.