Things to note after bone puncture

We all know that bone marrow puncture is a commonly used diagnostic method for diagnosing blood system diseases and certain tumors. Moreover, after this operation, be sure to keep the puncture site clean and dry to prevent infection. In addition, you should eat a light diet, eat more vegetables and fruits, drink plenty of water, try to eat less greasy, spicy and irritating food, and avoid smoking and drinking. So let’s take a look at the precautions for bone marrow puncture!

Some precautions for bone marrow puncture and blood collection

A bone marrow puncture:

1. Blood stop and coagulation tests should be performed before surgery. Patients with bleeding tendency should be particularly careful during the operation. People with hemophilia are prohibited from taking this test.

2. After the puncture needle enters the bone, avoid swinging it too much to prevent it from breaking.

3. When puncturing the sternum, do not use excessive force to avoid penetrating the inner bone plate.

4. If the bone feels hard during puncture and the medullary cavity cannot be penetrated, a bone X-ray examination should be performed to rule out marble bone disease. Do not force the operation to prevent the needle from breaking.

5. When aspirating bone marrow fluid, gradually increase the negative pressure. When performing cell morphology examination, the aspirated amount should not be too much, otherwise the bone marrow fluid will be diluted, but it should not be too little either.

6. Bone marrow fluid should be smeared immediately after extraction.

7. Bone marrow biopsy should be performed when multiple dry taps are performed.

Second blood sampling precautions

Issues that need to be paid attention to when drawing blood include: the site of blood collection, the patient's position during blood collection, the influence of tourniquet, the influence of infusion, and the influence of the type and amount of anticoagulants.

1. Blood collection site

Blood samples collected from different blood collection sites will produce different test results. It is unreasonable to collect blood sample from the finger today and from the vein tomorrow for the same patient and the same project. Blood samples collected from the earlobe, finger, or vein of the same patient and used for routine blood tests will give different results.

2. Effect of tourniquet

When the tourniquet is pressed for 40 seconds, total protein increases by 4% and aspartate transferase (AST) increases by 16%; when it exceeds 3 minutes, local blood concentration occurs, and serum iron, serum calcium, acid phosphatase (ACP), aspartate amidase (ASP), blood potassium and lactic acid increase, while pH decreases.

3. Patient Position

The specimens collected by the nurses when the patient is in different postures, such as lying, sitting or standing, will produce different test results. The total plasma volume of a normal person in a standing position is about 12% lower than that in a supine position, causing changes in the values ​​of hemoglobin (Hb), white blood cells (WBC), red blood cells (RBC), hematocrit (HCT), lipids, and proteins. Prolonged hemostasis time will cause changes in the coagulation system, and repeated fisting will increase blood potassium.

4. Use of anticoagulants

Some laboratory manuals suggest that the ratio of anticoagulant in coagulation test specimens is 1 part anticoagulant to 9 parts blood. The true meaning of this ratio is that 1 part of anticoagulant acts on 9 parts of plasma in a specimen with a normal hematocrit. In other words, the specific volume determines the plasma volume, and the plasma volume is determined by the amount of anticoagulant used.

The author has conducted experiments in which if the hematocrit of the same person was 46% (normal), 10% (anemia), or 80% (polycythemia), and they were all anticoagulated with the same anticoagulant in a 1:9 ratio, the APTT results were 33 seconds, 24 seconds, and 60 seconds. It can be seen that although the use of anticoagulants is a minor problem, it will have a great impact on clinical practice. In this case, the dosage of the inhibitor must be corrected.