Can The Dialyzer Be Reused for Hemodialysis Treatment?

Dialyzer, a vital consumable for kidney dialysis treatment, uses the principle of a semi-permeable membrane to introduce the blood from the renal failure patients and dialysate into the dialyzer at the same time, and making the two flow in opposite directions on both sides of the dialysis membrane, with the help of the two sides solute gradient, osmotic gradient, and hydraulic pressure gradient. This dispersion process can remove toxins and excessive water from the body while replenishing the body's needed substances and maintaining the balance of electrolytes and acid-base.

Dialyzers are mainly composed of support structures and dialysis membranes. The hollow fiber types are used most in clinical practice. Some hemodialyzers are designed to be reusable, with special construction and materials that can withstand multiple cleanings and sterilizations. Meanwhile, disposable dialyzers must be discarded after use and can not be reused. However, there has been controversy and confusion about whether dialyzers should be reused. We will explore this question and provide some explanation below.

Advantages and disadvantages of reuse dialyzers

(1) Eliminate the first-use syndrome.
Although many factors cause the first-use syndrome, such as the disinfectant of ethylene oxide, the membrane material, the cytokines produced by the blood contact of the dialysis membrane, etc., no matter what the causes, the probability of occurrence will decrease due to the repeated use of the dialyzer.

(2)Improve the bio-compatibility of the dialyzer and reduce the activation of the immune system.
After using the dialyzer, a layer of protein film is attached to the inner surface of the membrane, which can reduce the blood film reaction caused by the next dialysis, and alleviate complement activation, neutrophil degranulation, lymphocyte activation, microglobulin production, and cytokine release.

(3) Influence of clearance rate.
The clearance rate of creatinine and urea does not decrease. The reuse dialyzers disinfected with formalin and sodium hypochlorite added can ensure that the clearance rates of medium and large molecular substances (Vital12 and inulin) remain unchanged.

(4) Reduce hemodialysis costs.
There is no doubt that dialyzer reuse can reduce healthcare costs for renal failure patients and provide access to better but more expensive hemodialyzers
At the same time, the shortcomings of dialyzer reuse are also obvious.

(1) Adverse reactions to disinfectants
Peracetic acid disinfection will cause the denaturation and decomposition of the dialysis membrane, and also remove the proteins retained in the membrane due to repeated use, increasing the probability of complement activation. Formalin disinfection can cause Anti-N-antibody and skin allergies in patients

(2) Increase the chance of bacterial and endotoxin contamination of the dialyzer and increase the risk of cross-infection

(3) The performance of the dialyzer is influenced.
After the dialyzer is used several times, due to protein and blood clots blocking the fiber bundles, the effective area is reduced, and the clearance rate and ultrafiltration rate will gradually decrease. The common method to measure the fiber bundle volume of a dialyzer is to calculate the total volume of all fiber bundle lumens in the dialyzer. If the ratio of the total capacity to the brand-new dialyzer is less than 80%, the dialyzer cannot be used.

(4)Increase the chances of patients and medical staff being exposed to chemical reagents.
Based on the above analysis, cleaning and disinfection can make up for the shortcomings of reuse dialyzers to some extent. The dialyzer can only be reused after strict cleaning and disinfection procedures and passed tests to ensure no membrane rupture or blockage inside. Different from traditional manual reprocessing, the use of automatic dialyzer reprocessing machines introduces standardized processes into the dialyzer reprocessing to reduce errors in manual operations. The machine can automatically rinse, disinfect, test, and affuse, according to setting procedures and parameters, to improve the effect of dialysis treatment, while ensuring patient safety and hygiene.