When performing continuous mononuclear cell collection (CMNC) and mononuclear cell collection (MNC) procedures, properly configuring inlet:AC ratio and ACIR can be key to supporting safe, efficient outcomes.
You can configure inlet:AC ratio and ACIR before starting the procedure. You can then adjust if needed during the procedure based on the tolerance of the patient/donor (for ACIR) and flow of blood in the extracorporeal circuit (for inlet:AC ratio).
As with therapeutic procedures, it is recommended that you initially configure the inlet:AC ratio for CMNC and MNC protocols at the default value, which varies depending on the procedure type.
Inlet:AC ratio information
For CMNC, the default inlet:AC ratio is 12:1. For MNC, an inlet:AC ratio of 12:1 is also recommended.
The MNC protocol also has an inlet:AC ratio ramping feature. When configured to Yes, the procedure starts with an inlet:AC ratio of 8:1 and ramps to 12:1, providing a well-anticoagulated circuit from the beginning of the procedure. The inlet flow rate ramps along with the inlet:AC ratio.
Reminders: The inlet:AC ratio is the proportion of inlet volume to anticoagulant (AC) volume — or the number of pump rotations of the inlet pump to the AC pump. It determines the concentration of anticoagulant in the extracorporeal circuit. The number of parts of whole blood in the inlet volume is determined by the inlet:AC ratio you select in the Spectra Optia® Apheresis System. With the Spectra Optia system, the inlet volume is always composed of one part AC and the corresponding parts of whole blood (inlet:AC ratio).
You can change the inlet:AC ratio at any time during CMNC or MNC to address the anticoagulation needs of the procedure — but only after you carefully consider the effects on the collection.
- If you enter an inlet:AC ratio greater than 12:1, monitor the channel and the collect line closely for clumping.
- If you enter an inlet:AC ratio higher than 15:1, you will see an advisory message that you are exceeding the recommended limit.
It is important in any procedure to monitor for clumping. Watch your inbox for the next edition of Access Point, where we’ll discuss how to identify clumping in the circuit.
AC infusion rate for CMNC and MNC
AC infusion rate (ACIR) is the rate at which ACD-A is infused to the patient/donor. It is calculated as mL/min/L total blood volume (TBV). ACD-A contains citrate, so the AC infusion rate can also be thought of as a “citrate dose rate.”
Spectra Optia calculates the appropriate AC infusion rate based on the patient's/donor’s TBV. See the examples below.
The default ACIR is 0.8 mL/min/L TBV. However, you can configure a range of 0.8 to 1.2 mL/min/L TBV. When configuring a starting ACIR higher than 0.8 mL/min/L TBV, it is important to remember that not all patients will be able to tolerate a higher rate.
The main run screen will display a current ACIR that may fluctuate during the procedure but will never exceed the configured value or the maximum value entered on the run values screen.
The ACIR can be increased above 1.2 mL/min/L TBV. However, the system will run in Caution status within a range of 1.3 to 2.5 mL/min/L TBV.
Your AC management matters
Properly configuring inlet:AC ratio and ACIR is an important part of helping to prevent platelet activation, platelet clumps, and clotting. By understanding how to set initial values and adjust them during procedures, you lay the foundation for safe, efficient collection. If you have questions or want to learn more, please email us at or call 877.339.4228.
Sources:
Terumo Blood and Cell Technologies. Anticoagulant Management on the Spectra Optia Apheresis System. Successions Training Presentation. 2021. Part number TS-OPTI-01182.
Terumo Blood and Cell Technologies. Concepts of Anticoagulant Management. Training Presentation. 2022. Part number TS-OPTI-01105.
Terumo Blood and Cell Technologies. Continuous Mononuclear Cell Collection (Version 11 CMNC) Rx Only Procedure Training. 2021. Part number TS-OPTI-01014.
Terumo Blood and Cell Technologies. Spectra Optia System Mononuclear Cell Collection (Version 12 MNC) Procedure Training. 2023. Part number TS-OPTI-00123.