What is the normal value of CVP?

CVP is a value representing the atria and ventricles, and the normal value of CVP is generally between 0.05 and 0.12. Testing CVP can be of great help to the functional capacity of the heart and the ventricles. The normal value of CVP can be determined by testing instruments, and more accurate values ​​can also be detected for human blood circulation.

Components

CVP consists of four parts: ① right ventricular filling pressure; ② venous inner wall pressure; ③ venous systolic pressure and tension; ④ venous capillary pressure.

significance

Central venous pressure can be used clinically as an indicator of fluid replacement rate and amount.

Volume loading test - can be used as a treatment reference for patients with high CVP but still clinical manifestations of insufficient cardiac output. If 500 ml of fluid is rapidly infused within 20 minutes, and CVP does not increase significantly or even decreases; at the same time, blood pressure increases and heart rate decreases, it indicates that the patient has absolute or relative volume deficiency and the heart has the potential to continue to accept large amounts of infusion; otherwise, infusion must be cautious.

Determination of CVP is important for understanding effective circulating blood volume and cardiac function.

The magnitude of central venous pressure depends on the relationship between the heart's ejection capacity and the amount of venous blood returning to the heart. If the heart has a strong ejection capacity and can eject the blood returning to the heart into the arteries in time, the central venous pressure will be low. On the contrary, decreased ejection capacity due to heart failure and other reasons will lead to higher central venous pressure. Central venous pressure indicates the return of venous blood to the central vein and right atrium, but does not directly reflect blood volume. If CVP cannot be obtained due to etiology, the inferior vena cava under the diaphragm can also be measured instead of central venous pressure. Changes in central venous pressure generally occur earlier than changes in arterial pressure.

If the central venous pressure is less than 0.49 kPa, it means insufficient right atrium filling or insufficient blood volume; when the central venous pressure is greater than 1.47 kPa (15 cmH2O), it indicates heart failure, excessive contraction of the venous vascular bed, or increased pulmonary circulation resistance; if the CVP exceeds 1.96 kPa (20 cmH2O), it indicates congestive heart failure.

Indications

Indications for CVP testing:

1. Critically ill patients with severe trauma, various types of shock, acute circulatory failure, etc.

2. All kinds of major and medium surgeries, especially major cardiovascular, cranial, and abdominal surgeries.

3. Patients who require long-term infusion or total parenteral nutrition.

4. Patients who need to receive large amounts of blood transfusions and rapid fluid replacement.

way

Common ways to measure CVP pressure:

1. Right internal jugular vein.

2. Subclavian vein.

3. External jugular vein.

4. Femoral vein.