The ultrafiltration coefficient of the dialyzer is an important performance indicator used to measure the dialyzer's ability to remove water. It is usually expressed in ml/(h·mmHg). Specifically, it refers to the number of milliliters of liquid that passes through the membrane ultrafiltration per hour at a transmembrane pressure of 1mmHg. This coefficient reflects the water passing capacity of the dialyzer, and different dialyzers have different ultrafiltration coefficients. According to the size of the ultrafiltration coefficient, dialyzers can be divided into three types: high-flux, medium-flux and low-flux:12
The ultrafiltration coefficient of high-flux dialyzers is usually greater than 20ml/(h·mmHg), which is suitable for hemodiafiltration (HDF), high-efficiency dialysis and hemofiltration (HF) treatment.
The ultrafiltration coefficient of medium-flux dialyzers is between 10ml/(h·mmHg) and 20ml/(h·mmHg), which is suitable for maintenance hemodialysis treatment.
The ultrafiltration coefficient of low-flux dialyzers is between 4ml/(h·mmHg) and 10ml/(h·mmHg), which is suitable for patients who are undergoing dialysis for the first time or have imbalance symptoms.
In addition, in clinical applications, such as hemodiafiltration, the ultrafiltration coefficient of the dialyzer is usually required to be at least 20ml/(h·mmHg) to ensure sufficient water removal.