1. Plasmapheresis With (and Without) CRRT
9th International pCRRT Conference on
Pediatric Continuous Renal Replacement Therapy
August 31-September 2, 2017
Plasmapheresis With (and Without) CRRT
Jordan M. Symons, MD
University of Washington School of Medicine
Seattle Children’s Hospital

2. Apheresis “Apheresis”: Greek, “To take away or separate”
Blood perfuses extracorporeal circuit
Blood components separated; selected component removed
If large volume removed replacement is required
Uses include therapeutic indications or for blood component harvest
Hey!Pheresis®

5. American Society for Apheresis (AFSA)
List of indications with Fact Sheets
87 diseases/medical conditions; 179 indications
Rigorous review
Strength of recommendation; ratings of evidence
Many modalities along with TPE evaluated
Cytaphersis, extracorporeal photopheresis, immunoadsorption, rheopheresis, etc.

6. ASFA Fact Sheet Format
Schwartz et al. Journal of Clinical Apheresis 31:149–338 (2016)

7. Schwartz et al. Journal of Clinical Apheresis 31:149–338 (2016)

8. Therapeutic Apheresis in Critically Ill Patients
Added challenges to TPE in ICU
Critically ill patient – less stable
Already limited vascular access
More prone to complications
HypoCa, low BP, blood product reactions (TRALI)
Uncertainty of TPE effects in critically ill
Theory: non-specific immunomodulation
Practice: case-reports and small studies suggest improvement; RCTs do not support

9. Can TPE Help our Patients who have Sepsis with Multi-Organ Failure?
Why TPE might work
Remove inflammatory and antifibrinolytic mediators
Replenish anticoagulant proteins (FFP replacement)
Reverse derangement, restore hemostasis
Category III indication (ASFA Guidelines 2016)
“Optimum role of apheresis therapy is not established”
“Decision making should be individualized”
Grade 2B evidence
Selective endotoxin binding columns?
Some suggestion of improvement
In Europe and Asia; not in United States

10. Plasma Exchange: Technique

11. Components of Whole Blood
Separation and removal of individual components may be required for therapeutic need

12. Membrane Apheresis: Separates Components by Size
PheresisPhiltrePLUS
Plasmafilter: Similar to CRRT hemofilter but with larger pores

13. Membrane Apheresis: Separates Components by Size
Larger pores will allow proteins to pass through
Blood cells are restricted
Membrane system can be used for plasmapheresis, not cytapheresis
Creatinine 113 D
Urea 60 D
Glucose 180 D
Vancomycin
~1,500 D
Albumin
~66,000 D
IgG
~150,000 D

14. Apheresis by Centrifugation: Separates Components by Density
Hey!Pheresis®
Spinning centrifuge separates blood components by density
Specific component may be selected for removal by choosing appropriate layer
Permits plasmapheresis and cytapheresis

15. Apheresis by Centrifugation: Separates Components by Density
Hey!Pheresis®
Blood in from patient
RBCs
Blood return
Plasma
WBCs,
Plts

16. Fraction Removed from Plasma by Plasma Volume Replaced
y=e-x
Plasma volumes
Remaining fraction
IgG: only 45% intravascular
1.5 vol removes ~35% of total body IgG
Re-equilibration within ~2 days
Repeated session QOD often needed
0.223
(77.7% removed)

17. Plasma IgG Levels Before and After Apheresis

18. Pediatric Considerations
Used less often in children than adults
Diseases less common
Physicians less familiar
Technically more challenging
No pediatric devices
Circuit volume (blood prime?)
Vascular access
Complications more frequent than adults

19. Tandem Apheresis and CRRT
Apheresis and CRRT simultaneously (same access)
Avoid interruption of CRRT
Avoid risks/challenges associated with CRRT restart
Need appropriate preparation, procedures, systems in place to assure safety/efficiency

20. Apheresis in Parallel with CRRT
Return to Patient
NOTE: Reduce CRRT Qb by rate of apheresis Qb
From Patient

21. Apheresis in Parallel with CRRT
Return to Patient
NOTE: Likely need higher Qb for membrane
From Patient

22. Apheresis in Series with CRRT
Return to Patient
NOTE:
Qb is the SAME
From Patient

23. Apheresis in Series with CRRT
Return to Patient
From Patient

24. Secondary Plasma Processing
Return to Patient
Plasma regeneration
Adsorptive columns
Selective filters
From Patient

25. Summary
Therapeutic plasmapheresis may be necessary in critically ill patients, some of whom may also require CRRT
Utility in MODS/sepsis remains unclear
Apheresis can be combined with CRRT
Newer techniques may permit plasma regeneration of more selective apheresis

26. Thanks for your attention!