What are the principles and precautions for potassium supplementation?

Low potassium can cause some discomfort in the human body, such as weakness, palpitations, and confusion. In severe cases, breathing difficulties may occur, which is life-threatening. Therefore, the body must be supplemented with sufficient potassium every day. Potassium can be supplemented through food or by potassium injection. Some issues need to be paid attention to when supplementing potassium. What are the principles and precautions of potassium supplementation? Let’s take a look at it next.

1. Dangers of low potassium

1. Weakness and paralysis of the limbs, slow or absent tendon reflexes, and in severe cases, breathing difficulties.

2. Apathy, dull eyes, drowsiness, and confusion.

3. Nausea, vomiting, abdominal distension, intestinal paralysis.

4. Palpitations.

2. Oral potassium supplementation

Oral potassium is generally used. The preventive dose for adults is 10% potassium chloride 30-40 ml/d3-4 grams (each gram of potassium chloride contains 13.4 mmol of potassium).

Try to avoid using enteric-coated tablets and sustained-release tablets.

Oral administration of potassium chloride can easily cause gastrointestinal reactions, so potassium citrate is the best choice (1g of potassium citrate contains 4.5mmol of potassium).

3. Intravenous potassium supplementation

Intravenous potassium chloride is used for patients who cannot take it orally or who are severely potassium deficient. The commonly used concentration is 10-20 ml of 10% potassium chloride added to 1.0 L of 5% glucose solution. Each gram of potassium chloride must be dripped evenly for more than 30-40 minutes and cannot be injected intravenously.

The amount of potassium supplementation depends on the condition. As a preventive measure, adults usually supplement with 3 to 4 g/d of potassium chloride, and as a treatment, it is 4 to 6 g or more.

4. Precautions for potassium supplementation

Potassium supplementation is safe only when the urine volume is 30 ml/h or the daily urine volume is >700 ml. Patients with renal insufficiency who must take potassium supplements should be closely monitored.

If the concentration of potassium chloride injected intravenously is too high, it may irritate the veins and cause pain, or even venous spasm and thrombosis. (Thrombophlebitis) Maximum allowable potassium concentration 40mmol/l

Avoid infusion too quickly, as a sudden increase in serum potassium concentration may lead to cardiac arrest.

For patients with acidosis, hyperchloremia or liver damage, potassium glutamate can be considered. Each 6.3g vial contains 34mmol of potassium and can be added to 0.5L of glucose solution for intravenous drip.

K enters the cell very slowly, and it takes about 15 hours to reach a balance between inside and outside the cell. In cases of cellular dysfunction such as hypoxia and acidosis, the potassium balance time is longer, about 1 week or longer. Therefore, it takes several days to correct potassium deficiency. Do not rush or stop supplying it midway.

Under normal circumstances, a 70KG normal person has a total potassium of 3500mmol, of which 60mmol is extracellular potassium and the rest is intracellular potassium. The time required for intravenous potassium to enter the extracellular fluid and reach equilibrium with intracellular potassium is 48 hours for patients with heart failure and edema, and 24 hours for patients without heart failure and edema.

When potassium deficiency and hypocalcemia occur at the same time, attention should be paid to calcium supplementation, because the symptoms of hypocalcemia are often masked by hypokalemia. After hypokalemia is corrected, hypocalcemic convulsions may occur.

When potassium is supplemented in large quantities in a short period of time or for a long time, regular observation and measurement of serum potassium and electrocardiogram are required to avoid hyperkalemia.

It is not advisable to give sugar to patients with low potassium because potassium is consumed during glycolysis.

Dextrose-water dilution of intravenous potassium is not an ideal choice because glucose increases the patient's plasma insulin level, which can cause transient hypokalemia and aggravate symptoms.

5. Treatment of refractory hypokalemia

If the therapeutic effect of potassium supplementation is unsatisfactory and unstable after several days of treatment, it is called refractory hypokalemia.

1. Take appropriate amount of magnesium

2. Discover and treat the causes of extracellular potassium movement into cells.

3. Discover and treat the causes of renal potassium loss

4. Stop taking diuretics and treat vomiting and diarrhea

5. You can choose to use drugs that inhibit renal tubular potassium secretion, such as triamterene and spironolactone. However, it takes effect very slowly and has a long half-life, so hyperkalemia should be prevented when used.

6. If there is severe potassium deficiency in cells, increase the intensity of potassium supplementation!

7. If you are still unsatisfied with potassium supplementation after applying the above measures. You can try low-dose hormones. The specific principle is unknown. It may be that the hormones "allow" or so.

8. Although patients with periodic hypokalemic paralysis have very low blood potassium, they rarely suffer from fatal arrhythmias. If you blindly supplement potassium in large quantities, it can easily cause hyperkalemia. Treatment at this point focuses on maintaining respiratory muscle function.

6. Indications for stopping potassium supplementation

24 hours after stopping intravenous potassium supplementation, the blood potassium level is roughly normal and oral potassium supplementation can be used instead. Because the blood potassium level reaches 3.5mmol/L, it still means that the body is deficient in potassium by about 10%. Generally, potassium supplementation is required for 4 to 6 days. In severe cases, it may take 10 to 20 days to gradually correct the intracellular potassium deficiency.