Blood Flow Rate

Blood Flow Rate

**Q**

_{b}

- The rate of blood flow from the patient towards the filter
- Blood flow rates are typically slower than in intermittent dialysis, ranging from 150-200mL/min

Ultrafiltrate Rate

Ultrafiltrate Rate

**Q**

_{uf}

- The rate at which ultrafiltrate is produced by hydrostatic pressure across the membrane during convective therapies
- It is influenced by the blood flow rate and the filtration fraction

Dialysate Flow Rate

Dialysate Flow Rate

**Q**

_{d}

- The flow rate of dialysis fluid in dialytic therapies
- Standard flow rates range from 8-50 mL/min

Effluent Rate

(Dose)

(Dose)

Effluent Rate

(Dose)

(Dose)

**Q**

_{ef}

- The effluent flow rate is the equivalent to ultrafiltration rate Quf in continuous haemofiltration, Qd in continuous haemodialysis, and both Quf & Qd in continuous hemodiafiltration
- It is analogous to the ‘dose’ in continuous therapies
- Dosing is weight-based and is typically prescribed at a dose ranging from 20 mL/kg/hr to 35 mL/kg/hr

Substitution Fluid Rate

Substitution Fluid Rate

**Q**

_{s}

- Techniques in which produce a volume of ultrafiltrate require replacement of this fluid with a substitute fluid to prevent significant loss of volume.
- The rate of substitution fluid describes the rate at which this replacement fluid is added to the plasma

Net Ultrafiltrate Rate

Net Ultrafiltrate Rate

**Q**

_{net}

- Represents the overall rate of fluid removal
- It is the difference between the total effluent removed (Qef) minus the volume of replacement therapy
- The fluid removal rate can be tailored by the machine to meet the total removal goal of the patient