Transfusion Triggers. Richard Soutar January 2012

Transcription

1 Transfusion Triggers Richard Soutar January

2 Educational objectives: To understand the risks of transfusion - the known, the uncertain and unknown To understand the fear of the unknown in Transfusion Medicine To understand that the "trigger" for transfusion varies with the patient and the clinical setting To consider alternatives to transfusion To appreciate that despite the huge number of transfusions undertaken that the evidence base is weak To have some appreciation of the other blood components: FFP, Platelets and Albumin 2

3 Transfusion Triggers 1. Background 2. The problems with blood 3. Who and when to transfuse 4. Trial Data to help decision making 5. Guidelines and local policies 6. Alternatives to transfusion 3

4 Transfusion triggers the background Cost per unit: RBC= Platelets= Increased and more sophisticated testing,leucodepletion, importation of plasma, BBT program = Increasing cost No end in sight of safety goal e.g. next step prion filtration see: McClelland B, Contreras M. BMJ 2005; 330: and Mortimer P. BMJ 2002; 325: and reply Murphy et al. 4

5 Transfusion triggers Where does blood go? 6% 41% 53% Surgical (Ortho 10%, CABG 11%) Medical (Haem - 16%) Ob/Gyn 5

6 Transfusion so what s the problem? Death 1: 500,000 Morbidity 1.1: 100,000 (Bacterial 0.2, TRALI 0.6) Estimated frequency of virally infected donations entering UK blood supply during : HIV 0.19 Per million units HCV 0.01 Per million units HBV 1.09 Per million units Fear of the unknown! 6

7 Variant Creuzfeldt-Jacob Disease (vcjd) 4 cases of vcjd infection associated with blood transfusion: three of the four recipients developed symptoms of vcjd All 4 cases received transfusions of non-leucodepleted red cells between 1996 and 1999 Asymptomatic vcjd abnormal prion protein in one haemophilia patient receiving human factor concentrate (2009) Potential liability Burton judgement for HCV a product UK hospitals instructed to make plans for blood shortages Hence drive to optimise blood use 7

8 Decision to Transfuse Depends on setting: Peri-operative Massive blood loss Chronic transfusion Overall remarkable lack of evidence! 8

9 Peri-operative Transfusion Attempted coverage in SIGN Guideline #54 Oct 01 (Online updates 2004 and 2009) Peri-operative Blood transfusion for Elective Surgery (doesn t cover chronic disease) 9

10 How low can Hb safely go in fit / resting adults? Weiskopf et al JAMA 1998; 279: O2 delivery maintained to Hb of 50 g/l No increase in CO in healthy till Hb < 7 Healing not impaired till HCT < 0.15 Non-uraemic no association HCT and Bleeding Time 10

11 Carson JL et al 2002 More trial data 10 RCT restrictive use (Hb 7-9) assoc 1/3 in RBC exposure Approx 1 unit per transfused patient No effect on mortality, morbidity, length of hospitalisation Only decent RTC in ITU setting (Hebert et al 1999) Restrictive (Hb 7-9) did as well as liberal (HB 10-12) but possibly not in less well with cardiac disease 11

12 SIGN recommendations Transfusion is required at Hb values < 70g/l Patients with c/v disease, or high incidence of covert c/v disease are likely to benefit when Hb falls <90g/l Transfusion is unjustified at Hb values > 100g/l Can any other data help us? 12

13 Jehovah s witnesses Carson et al 2002 looked at 300 Jehovah s witnesses with Hb <8 postop Hb % mortality 9.4% morbidity/mortality Hb % mortality 22% morbidity/mortality Hb % mortality 29% morbidity/mortality Hb % mortality 58% morbidity/morbidity odds of death increased 2.5x per gram decrease in post-op HB 13

14 Local Policy Hb % mortality 22% morbidity/mortality Not acceptable! Therefore NGT transfusion trigger is taken as 8 not 7g/dl 14

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16 Caveat Remember relates to anaemia not hypovolaemia Requires clinical judgement to avoid disasters in the bleeding / haemolysing patient 16

17 Massive Haemorrhage Issues relate more to blood product support esp FFP? Any evidence of any use of FFP anywhere outwith TTP (McClelland DBL, Contreras M, J R Coll Physicians Edinb 2005; 35: 2-4) (McClelland B, Contreras M, BMJ 2005; 330: and discussion) Computer modeling (Hirshberg et al 2003) Under-estimation of clotting factor dilution lead to revised massive haemorrhage protocol with early, empiric FFP 17

18 Massive Haemorrhage See handout and North Glasgow intranet pdf 18

19 Transfusion for Chronic Anaemia What are we doing/trying to achieve? Prevent death from anaemia - Hb 7-8 What about QoL? 19

20 Cancer: no anaemia score 68, normals score 75 Cella D, Jin-shei L, Chih-Hung C, Peterman A, Slavin M. Fatigue in cancer patients compared with fatigue in the general United States population. Cancer 2002; 94:

21 Chronic anaemia - Cancer Graph suggests that mild anaemia has a marked effect on quality of life (QoL) Should we aim to keep Hb above mild anaemia? (>10, >12) Data used for rationale for EPO - why not red cells? 21

22 Have guidelines set up for the post-op situation led us to under-transfuse our cancer patients? And If we re worried by blood what s the alternative? 22

23 Blood Alternatives Pre-op optimisation Autologous pre-deposit Intra-operative cell salvage Don t t transfuse transfusion guidelines - see above Minimising blood loss Post-operative operative cell savage Blood substitutes Stimulation of erythropoiesis 23

24 NBS Systematic Review Initiative PAD use of intervention not recommended ANH limited use, further research needed (low priority) Cell salvage definite benefit but research on cost effectiveness Fibrin sealant - limited use, further research Desmopressin not recommended Aprotonin licence suspended N Eng J Med: 2006; 354: and Transfusion 2006; 46: TXA/EACA - further research needed 24

25 Erythropoietin Established in renal failure Effective in oncology but? Cost effective NICE guidance not cost effective Cost RBC 250/month, c.f. 1,200 for EPO, one course ~ 4K saves 1 unit of blood In orthopaedic surgery HTBS evaluated No! Unless in certain circumstances 25

26 Albumin 20 % often used to treat Hypoalbuminaemia? Evidence of benefit but may speed discharge 4 % used as volume expander controversial Finfer et al. N Eng J Med 2004: 350: 2247 No benefit compared with 0.9% NaCl 26

27 Platelets Trial data to support use in stable cancer patients: Heckman KD et al J Clin Oncol 1997; 15: Rebulla P et al N Eng J med 1997; 337(26): Zumberg MS etal Biol Blood Mar Trans 2002; 8: ICU setting based on expert opinion Platelet transfusion may be associated with worse outcome in cardiac surgery Spiess et al Transfusion 2004; 44:

28 Platelets continued TOPPs trial (Trial Of Prophylactic Platelet Transfusions in patients with Haematological Malignancies) Muticentre RCT, BOC Scottish site (Oct 2008) 347 patients randomised to date 29 Patients from BOC 28

29 FFP Based on BCSH document Empiric release of 4 x FFP for massive haemorrhage 29

30 Guidelines BCSH lots of them! Guidelines for the clinical use of red cell transfusions. Br J Haematol 2001; 113: Transfusion Guidelines For Neonates and Older Children. Br J Haematol 2004; 124, (amended 2007) Guidelines for the use of Fresh Frozen Plasma, Cryoprecipitate and Cryosupernatant. Br J Haematol 2004; 126, (amended 2007) Guidelines For The Use Of Platelet Transfusions. Br J Haematol 2003; 122,

31 Thank you 31 31