Normal value of venous pressure in hemodialysis

Hemodialysis is the most commonly used method of blood purification in modern medicine. Hemodialysis is mainly used for patients with renal failure, so hemodialysis is also called artificial kidney. Before hemodialysis is implemented, the patient must undergo many physical examinations to determine whether the patient's body is suitable for hemodialysis. Checking venous blood pressure is a very important test. So what is the normal value of venous blood pressure before hemodialysis?

Venous pressure is generally 20~150mmHg, and 90~180mmHg during artificial blood vessel dialysis.

Reasons for high venous pressure alarm: ① The venous cavity filter is blocked by coagulation; ② The blood tube on the venous side is folded, and blood return is blocked; ③ The patient's vein is stenotic and thrombotic; ④ The patient is in a side-lying position and the vein is compressed; ⑤ The venous needle sticks to the blood vessel wall, making blood return difficult or the venous needle is displaced, causing swelling at the puncture site; ⑥ The venous needle is small and has a high blood flow; ⑦ The patient has excessive ultrafiltration and the dialyzer ultrafiltration coefficient does not meet the standard; ⑧ The venous pressure sensor is faulty or the working point drifts.

Reasons for low venous pressure alarm: ① The blood pump stops; ② The connection between the blood tube and the needle is loose; ③ The connection between the blood tube is not tight; ④ It is difficult to draw blood from the arterial end and the actual blood flow is low; ⑤ The patient's blood pressure drops; ⑥ The venous needle falls off; ⑦ The arterial pot or dialyzer is severely coagulated; ⑧ The venous detector is not connected, the detector pipeline clamp is not opened, or the detector itself has quality problems; ⑨ The venous pressure sensor is faulty or the working point drifts.

Emergency handling when an alarm occurs

When a venous pressure alarm occurs, the dialysis machine enters bypass mode, the blood pump stops working, and the venous line clamp is closed. The nursing staff should promptly detect the alarm, press the mute button, check the alarm content and the patient's condition, and handle it correctly.

Treatment of high venous pressure alarm: ① Inject normal saline from the insufflation port to pre-flush the dialyzer and pipelines, and observe whether there is coagulation in the venous filter. If the coagulation is serious, the venous blood line should be replaced immediately, and the heparin dosage should be carefully checked. ② Check whether the blood line is folded under pressure, and properly fix the blood line. ③ Check whether the arteriovenous end is connected reversely, and correct it in time. ④ Check the venous puncture needle. If it sticks to the blood vessel wall, adjust the position of the needle in time. If the puncture site is swollen, the venous puncture needs to be replaced again. ⑤ If the patient is suspected of venous stenosis, angiography can be performed and surgical treatment can be performed. ⑥ If it is a machine failure, report it to the repair engineer and the patient will move the machine to continue dialysis.

The reason for the low venous pressure alarm: ① First check the vascular access, the fixation of the puncture needle, whether it is tightly connected to the blood tube, whether there is any blood leakage at the joints of the blood tube, and deal with the problem accordingly; ② Measure the patient's blood pressure to determine whether the blood flow is reduced due to a drop in blood pressure, and adjust the venous pressure alarm limit in time when the blood flow changes; ③ Inject normal saline from the infusion port to pre-flush the dialyzer and pipelines, and observe whether the arterial pot and dialyzer are coagulated. If the coagulation is serious, replace the dialyzer and blood tube immediately, and check whether the heparin dosage is correct; ④ Determine the blood flow at the fistula, adjust the position of the arterial needle, and the central venous catheter needs to appropriately adjust the position of the catheter or let the patient change his position, etc., to ensure blood flow; ⑤ Connect the venous detector in time and open the detector pipeline clamp. If the venous detector is leaking or blocked, it needs to be replaced to truly reflect the venous pressure situation. ⑥ If it is a machine failure, report it to the repair engineer and the patient will move the machine to continue dialysis.

Provide psychological comfort to patients: When venous pressure is outside the normal range during dialysis, the dialysis machine will emit a buzzing alarm sound and the red light will flash. While alerting the nursing staff, it will also have a certain negative stimulation on the patient, causing him to worry that his health is threatened and become anxious. At this time, the nursing staff should remain calm, comfort the patient, explain the situation, actively find the cause, resolve the fault as soon as possible, enter the normal dialysis state, and eliminate the patient's worries. After the alarm is handled, the patient inspection should be strengthened. A serious and meticulous work attitude can increase the patient's sense of security.