Hemodialysis: Things to Know

With the development of renal replacement treatments, especially hemodialysis has helped to prolong the life of patients with chronic kidney disease stage 5 prolonging life for decades, thanks to which the quality of life of the patient is also much better.

1. What is hemodialysis?

Hemodialysis is an out-of-body dialysis method, an extra-body circulation will be established. The patient's blood will be given a dialysis machine filter to filter out the residues of the metabolism and excess water, after which the blood will be returned to the body.

Hemodialysis is based on the following mechanisms:

  • Ultrafiltular mechanism: Because the pressure of the blood pump is higher than the fluid pump pressure, the hydrostatic pressure of the blood cavity will be higher than the pressure in the fluid cavity, the water from the blood cavity will move to the fluid cavity and pull along the dissolved substances.
  • Fractional diffusion mechanism: Soluble substances such as urea, creatinine and other small molecular weight substances with high concentrations in the blood will diffuse from the blood to the filtration fluid cavity due to the difference in concentration.
  • Flow-through mechanism: After a while when the fluid dissolves in the blood cavity and the filtration fluid cavity is balanced, the diffusion process decreases in effect.

To limit the above process, in hemodialysis, blood and dialysis will be run in opposite directions to reduce concentration balance and improve filtration efficiency.


Hemodialysis Procedures

2. When is hemodialysis required?

Patients with stage 5 chronic kidney disease (also known as terminal) will be prescribed dialysis. At this stage, the patient's level of dialysis has decreased to a very low level <15 ml/ph/1.73 m2 thận hầu như đã mất hoàn toàn chức năng, các chất độc của quá trình chuyển hóa tích tụ trong cơ thể. Patients must receive renal replacement treatment to sustain life. In patients with diabetes mellitus, hemodialysis is in dinhed earlier.

Hemodialysis is also used in the treatment of acute renal failure and dialysis when poisoning, drug overdose.

3. What should be prepared before hemodialysis?

In patients with stage 5 chronic kidney disease, prior to the first dialysis session from a few weeks to several months, the patient should undergo intravenous artery articular surgery (also known as FAV surgery) to create a seam between the artery and the vein in the hand. Because during dialysis, the blood flow through the filtration system must ensure a flow not less than 300ml / min, the pressure necessary to suck blood from the bridge must reach about -100 mmHg, the pressure to return blood to the circulation must also be at +100 mmHg. FAV helps to increase blood flow to meet the requirements of the principle of hemodialysis.


Preparation before hemodialysis

4. Possible complications of hemodialysis

During hemodialysis, patients may experience the following complications:

  • Hypotension: Occurs in 20-30% of patients. This can be caused by high blood pumping rates, excessive hyperfiltling, high-temperature filtration, or patients taking blood pressure medications before dialysis, patients with cardiovascular diseases such as heart failure, arrhythmias,…
  • Cramps: Usually caused by hypotension, excessive ultrafiltification, or low sodium filtration. Cramps occur in 5-20% of patients.
  • Nausea and vomiting: Occurs in 5-15% of patients, being an early syndrome of osmoatic imbalance syndrome, which is often associated with hypotension.
  • Chest pain, back pain: Common when patients have myocardial anemia or when using filters for the first time. The incidence is 2-5% of patients.
  • Itching: Itching occurs 5% of patients on hemodialysis. Itching is usually caused by patients allergic to certain substances in the filter fluid

During dialysis if the body notices any abnormal signs, the patient must immediately notify the medical staff for timely intervention and treatment.

Patients with end-stage chronic renal failure when treated with hemodialysis should be especially tight in the diet. Limit foods high in salt and potassium, provide protein to a sufficient level, patients should not drink too much water to limit the risk of edema.

Patients need to monitor their weight daily, to determine the excess volume of water, which will help to facilitate dialysis, the dialysis machine will help the patient to take out the excess volume.

Patients with stage 5 chronic kidney disease when hemodialysis has been prescribed, dialysis will last a lifetime. Patients will usually have dialysis 3 times per week, each lasting 3-4 hours. Therefore, patients need to arrange work and activities to suit dialysis.

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  • 5 stages of chronic renal failure
  • Emergency renal failure is highly likely to die
  • Progress and complications of chronic renal failure

  • Emergency renal failure is highly likely to die
  • Dialysis in dialysis is insular
  • Caution when using dies in the treatment of renal failure

About: John Smith

b1ffdb54307529964874ff53a5c5de33?s=90&r=gI am the author of Share99.net. I had been working in Vinmec International General Hospital for over 10 years. I dedicate my passion on every post in this site.


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