Case Study 1: Red Cell Exchange

Transcription

1 Case Study 1: Red Cell Exchange Education Session VI: Pediatric Apheresis Leon Su, MD Section Chief, Transfusion Medicine and Apheresis

2 None Disclosures

3 8 year old female SCD History of CVA in 2012 Hgb S levels well maintained on chronic tx (20-30%) Ferritins and Iron in liver (MRI quantification) elevated despite chelation therapy Began chronic exchange therapy in early 2015 Patient HM

4 When to consider outpatient red cell exchange (Sickle cell disease, non-acute) Stroke prophylaxis/iron overload prevention ASFA Category II, Recommendation 1C Vaso-occlusive pain crises ASFA Category III, Recommendation 2C Pre-Op management ASFA Category III, Recommendation 2A Exchange Transfusion Reduced transfusional iron Unrestricted by baseline HCT with ability to target end HCT Multiple donor exposures Simple Transfusion Iron overload more common Restricted to lower baseline HCTs to avoid high viscosity Less donor exposure Schwartz et al. J. Clin Apheresis 28: , 2013 Kim et al. Blood 83(4): , 1994

5 Access Options Peripheral access 18 gauge dialysis-type steel needles 18 to 20 gauge angiocaths AV fistula and grafts Central venous catheters Tunneled and Nontunneled Ports (indicated for power injection) Single and bilateral Dual lumen

6 Double lumen ports 9.5 Bard powerport: ml/min 11.4 Angiodynamics dual lumen smart port: ml/min Considerations when choosing port Previous history of clots and infections History of peripheral access Evaluation by apheresis nurses Appropriate size based on patient

7 Preparing a child for port access: child life support resources They looked into my mouth and into my ears; they looked into my eyes and touched my tummy. But, they never looked at me. (7 year old patient)

8 What is a Child Life Specialist? Assist children in managing/understanding healthcare experiences Assessment Play: therapeutic play, medical play, developmental play Preparation Coping strategies Pre-admission tours Educate End of Life/ Bereavement work Sibling support Back to school Supervise

9 Child Life Support

10 Initial access

11 Ready for exchange

12 Blood Product Selection HM is DcE/DcE with antibody to little e. Requires C, K, Fy(a), Jk(b), S and little e negative blood Institutional Guidelines Type and screen 1-3 days prior to exchange Rh and Kell matched if negative screen Also Fy, Jk and S matched if positive screen Hgb S negative, no irradiation unless other indication < 14 days old Communication with blood bank and blood provider paramount to ensure availability of blood

13 Prime versus nonprime Extracorporeal volume (ECV) Blood warmer volume (BWV) 10-15% of TBV should not exceed ECV + BWV If not priming, intraprocedure HCT can be calculated Optia Prime with saline/albumin during RBCX results in a mix of replacement fluid (RBCs) with saline/albumin in the return line to a HCT = patient

14 Monitoring Hgb S and procedure parameters Pre and post Hgb S levels Target pre procedure Hgb S levels below 30% HM fluctuates between 10-30% pre and post procedure Frequency start at every 4 weeks Typical FCR 40% AC infusion rate 1.1 with 15 mg/kg/hr Calcium Gluconate or AC infusion rate 0.8 with no calcium WB:AC ratio 15:1

15 Ferritin Iron (mg) Procedure 14 and 15 had frequency of 5 weeks before procedure Pre HCT Post HCT Depletion performed with procedures 4, 12 and 13 Minimizing iron gain Lower end target HCT Combining with depletion End target HCT what s the right target?

16 Adverse reactions HM tolerates procedures well and has not had any adverse events over her 1.5 year course Premedicated with Tylenol and Benadryl Other patients with hypotensive reactions and allergic reactions Managed with corticosteroids and fluid boluses, one patient with washed red cells

17 Summary HM continues to have good Hgb S control at 4 week interval RBCX Her Ferritins came down from the 1500s to the s with exchange and better compliance with iron chelation therapy. Plan is to keep at 4 week intervals which will hopefully help pre procedure HCTs stay >24% and allow for modest depletion with exchanges May require splenectomy down the road

18 Thank you!