This document provides an overview of sickle cell disease (SCD) and red blood cell exchange transfusions. It discusses the pathophysiology and complications of SCD, including increased blood viscosity and reduced blood flow. Treatment options are presented, with red blood cell exchange transfusions explained as removing sickle cells and replacing them with normal red blood cells to improve oxygen carrying capacity and reduce complications. The document covers procedural considerations for red blood cell exchange transfusions, such as goals, potential complications, and their management. It provides resources for further information.

1. Overview of Apheresis
and Sickle Cell Disease
Raúl H. Morales-Borges, MD
Medical Director
American Red Cross
Blood Services
Puerto Rico Region

2. What is Sickle Cell Disease?
• Incidence
• Pathophysiology
• Treatment
• Apheresis Considerations
– Patient History
– Amount and Type of blood
– Adverse Reactions

4. Incidence
30 Years Ago
- Infectious Disease
- Stroke
- Average Life Span
Today
- Infectious Disease
- Multiple Organs
- Average Life Span

5. Peripheral Blood Smear
Sickle Cells

6. Illustration
of the
formation
of sickle
cells
From Raj, A. Sickle Cell Disease in
Pediatrics.
Emedicine.com/ped/topic2096.htm

7. Organs
Affected
by SCD

8. Hereditary Genealogy of SCD

9. How does SCD cause problems?
• Increased blood viscosity
– Limits blood flow
– Promotes red cell sickling
– Promotes cell-cell interactions
– Activation of coagulation systems
• Increased cardiac output
• Expanded plasma volume
• Will likely have a lower hemaglobin/hematocrit

11. Sickled cells
and their
effect on
blood flow
from

12. Velocity = pi (pressure) (radius of tube)4
8 (length of tube) (viscosity)
Classic Poiseuille equation for laminar
flow of a fluid through a straight tube

14. Lungs
Deoxygenated RBCs Oxygenated RBCs
Peripheral circulation

15. What does this mean to my patient?
• By doubling the viscosity, the velocity is cut in
half.
• Flow is slower in vessels of small radius.
– arterioles, venules, capillaries
• Flow is slower in vessels with lower pressures.
– Venules
• Vaso-occlusive events and Red Cell Destruction

17. Treatment Options
• Prophylactic vaccines and antibiotics
• Hydroxyurea
• Aspirin
• Iron Chelation Therapy
• Simple Transfusions
• Red Cell Exchange

18. How do these issues impact my patient?
• Acute
– Vaso-occlusive stroke
– Acute chest syndrome
– Multiorgan failure syndrome
– Right upper quadrant syndrome
– Surgery/pregnancy
• Chronic
– Primary and secondary stroke prevention
– Multi-organ problems

19. What are the potential complications of
SCD that may be treated by apheresis?
• Acute infarctive stroke
• Acute chest syndrome
• Multi-organ failure syndrome
• Right upper quadrant syndrome
• ? Priapism
• ? Acute pain episode
• ? Pregnancy

20. How does a RBC exchange transfusion
help my patient?
• Removing sickle cells and replacing them with
normal red cells will….
– Improve the oxygen-carrying capacity of the blood
– Decrease blood viscosity
– Reduce vaso-occlusive events
– Reduce hemolytic complications

21. Sickled cells
and their
effect on
blood flow
from

22. What are your treatment options?
• Simple red blood cell (RBC) transfusions
• Partial RBC exchange transfusion
• Automated RBC exchange transfusion
– Partial exchange transfusion
– Full exchange transfusion

23. Advantages & Disadvantages
• Simple Transfusion • Exchange Transfusion
• Sickle cells remain • Removes % of sickle cells
• Increases viscosity • Maintains viscosity
• Increased iron load • No increases in iron load
• Volume shift • Volume shift?
• Easier vascular access • May need great access
• Time • Time
• Transfusion complications • Transfusion complications

24. Procedural Considerations
• Hydration • Extracorporeal volume
• Medication • Vascular Access
– Diuretics – Indwelling line or
– ACE inhibitors graft
• Anemia – Temporary femoral
– Simple transfusion dialysis catheters
– Blood prime – Ports
• RBCs

25. Line Access Issues and Solutions
- Peripheral access
- Catheters
- Ports

26. Line Access Issues

27. Antigen – Antibody Reactions
Y
SENSITIZATION
Y
Y
ABO
Y
Red Cell
Y
Y
Y
Y
Rh (D, C, c, E, e)
Y
Y Kell (K, k)
Y
Y
Y
Kidd (Jka, Jkb)
Y
Y
Y
Y
Y Duffy (Fya, Fyb)
Y
Other: S, U, V, hrb
Y
Antibody
Y
Y
Y
Y
Y
Y

28. Goal: Less than 30%
• Final Hematocrit
– Raise it no more than 3% (why?)
• Final sickle cell % of less than 30 (why?)
– Approximately 1.5 red cell volumes in an
untransfused patient.
– Approximately 1 red cell volume in a recently
transfused patient.

30. What does this mean to my patient?
• By doubling the viscosity, the velocity is cut in
half.
• Flow is slower in vessels of small radius.
– arterioles, venules, capillaries
• Flow is slower in vessels with lower pressures.
– Venules
• Vaso-occlusive events and Red Cell Destruction

31. How much to exchange?
• Prior to the exchange, need:
– Starting hematocrit
– Sickle cell percentage
– Weight in kg
– Total red cell volume

32. Calculating the Red Cell Volume
Red cell volume = (*TBV) (hematocrit)
*TBV = estimated total blood volume
- adult male: 60 – 75 (70)cc per kg
- adult female: 55 – 70 (65)cc per kg
- infant/child: 80/70cc per kg

33. Procedural Considerations
• Removal of Normal Plasma Constituents
• Lowers Plasma Cations – Calcium
• Alteration of Pharmacodynamics
• May Alter Laboratory Test Results

34. Possible Complications
• Acute transfusion reactions
• Vascular access complications
• Procedural complications
• Delayed transfusion reactions
• Other

35. Potential Apheresis Adverse Reactions
• Anxiety • Transfusion Reactions
– Hyperventilation – Allergic reactions
– Vasovagal – ABO-incompatibility
• Procedural – Bacterial sepsis
– Hypocalcemia – TRALI
– Hemolysis – Anaphylactic
– Hypo/Hypervolemia Reactions
– Mechanical • Thrombosis or
Hemorrhage

36. Paresthesia
Consider:
Consider:
Hyperventilation,
Oral calcium,
Pause Procedure Citrate toxicity
Slow infusion rate
Vasovagal
Yes Consider:
Consider:
Oral calcium,
Slow pulse Hyperventilation,
Knees above head
Citrate toxicity
Slow infusion rate
Vasovagal
Yes
Consider:
Nausea & Consider:
IV Calcium,
Vomiting Citrate toxicity
Cold compresses
ACE inhibitor
Slow infusion rate
Yes
Consider:
Consider:
Convulsions IV Calcium,
Citrate Toxicity,
Knees above head
Vasovagal
Call back-up

37. Erythema,
Itching,
Hives
Respiratory
Symptoms
No Yes
Mild, Stop
Pause Procedure, Call Backup
Antihistamine
Steroids
Severe,
Resume, Stop procedure,
Redose if needed ABCs
Call Backup

38. Hypotension Consider…
Dehydration,
Pause Procedure,
Vasovagal
Check Vital Signs
Yes
Change in Hyperventilation,
pulse rate Vasovagal
Yes
Hypovolemia,
dyspnea Hyperventilation,
TRALI
Vasovagal
Cardiogenic Shock
Yes
Sepsis,
fever Bacterial contamination,
ABO incompatibility
TRALI

39. Issues of Exchange Transfusion in
SCD
• No clear cut guidelines for palliative chronic exchange
transfusion for painful vaso-occlusive crisis in adults
patients (Navaid M, Melvin T: Am J Hosp Palliat Care 2010 May;
27(3):215-218).
• Good results in the use of partial exchange transfusion
in the management of SCD in a perioperative setting
(Jaeckel R, Thieme M, Czezlick E, Sablotzki A: Journal of Medical Case
Reports 2010; 4:82).
• Not effective in SCD with coexisting warm
autoantibody haemolysis (Baron JM, Baron BW: Blood Transfus
2010; 8:303-306).

40. Summary
• What is SCD?
• What are some of the complications of SCD?
• What are some of the available treatment options?
• How do RBC exchange transfusion help?
• What are some of the indications for treatment?

41. Communication

42. Summary
• What are some of the factors to be considered prior to
beginning a RBC exchange procedure?
• What are the goals of a RBC exchange?
• What are some of the possible complications during
and following a RBC exchange?
• How do we recognize and manage these complications?

43. References
• Sharon, BI. Management of Congenital Hemolytic Anemias. In
Rossi’s Principles of Transfusion Medicine. 4th ed. AABB Press, 2009.
• Special Review Issue of the Journal of Clinical Apheresis: Clinical
Applications of Therapeutic Apheresis. 2010. ASFA website.
http://apheresis.org.
• McLeod BC, Triulzi DJ. Therapeutic Apheresis. A Physician’s
Handbook, Bethesda, MD: American Association of Blood
Banks, 2005.
• McLeod BC, Weinstein R, Winters, JL, Szczepiorkowski, ZM
eds. Apheresis: Principles and Practice. 3nd ed. Bethesda, MD:
AABB Press, 2010.
• Popovsky MA, ed. Transfusion Reactions, 3nd ed. Bethesda, MD:
AABB Press, 2007.
• The Food and Drug Administration/Center for Biologics
Evaluation and Research: Code of Federal Regulations, Title 21
– Food and Drugs. http://www.fda.gov.

44. References
• Technical manual, 16th ed. Bethesda, MD: American
Association of Blood Banks, 2008.
• Standards for blood banks and transfusion services, 26-27th ed.
Bethesda, MD: American Association of Blood Banks, 2010-11.
• Swerdlow P. Red Cell Exchange. Hematology. 2006:48-53.
http://asheducationbook.hematologylibrary.org/cgi/content/ful
l/2006/1/48
• Lottenberg R & Hassell K. An evidence-based approach to the
treatment of adults with sickle cell disease. Hematology. 2005: 58-
65.
• Gladwin M & Kato G. Sickle cell disease: Advances in
pathogenesis and management. Hematology. 2005:51-57.
• Immunohematology, American Red Cross.2006:22:101-148.

45. Dr. Raúl H. Morales Borges
Hematólogo/Oncólogo
• Cruz Roja Americana de • Ashford Medical Center
PR – Suite # 107
– Servicios de Sangre – Condado, San Juan
– Ubicados en el Centro – Tel. 787-722-0412
Medico de PR – Fax 787-723-0554
– Tel. 787-759-8100 – ihoa@coqui.net
– Ext. 3873 – www.ihoapr.com
– Cel. 787-505-5814
– MoralesBorgesR@usa.redcross.org