You are the Intensivist looking after a 30-year-old male, with no significant past medical history, who has been in the Intensive Care Unit for eight days with severe community acquired pneumonia and septic shock.

Although there are no overt signs of bleeding, his haemoglobin has slowly dropped and is now 65 g/L. He has been recommenced on low dose noradrenaline and you have decided to transfuse one unit of packed cells.

His wife has concerns about the “safety” of this and refuses to consent until she speaks to you.

Outline the key points of your discussion with the patient’s wife, including the pros and cons of, and alternatives to blood transfusion in this context.

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College Answer

Discussion should cover:

  • Involving patient If competent
  • Ensure wife appropriate patient advocate
  • Listening to and clarifying wife’s concerns including religious / cultural objections
  • Patient’s wishes if known
  • Pros and cons of transfusion in this situation
  • Non-transfusion strategies

Pros:

  • Transfusion at this low threshold is evidence based i.e. consistent with a restrictive approach as advocated by the National Guidelines. Transfusion is probably appropriate given the information available, but is not mandated.
  • Administration of a single unit followed by reassessment is consistent with the National Guidelines. May improve oxygen delivery, enable cessation of noradrenaline, and potentially positively affect
  • organ function and outcomes.
  • Red cell transfusion is safe, with risks of viral transmission (HIV & HCV), CJD and fatal haemolytic reactions being less than 1 in 1 million.

Cons:

  • There is insufficient evidence to suggest that transfusion in this situation will have a positive effect on mortality.
  • This young man is relatively well compensated (although on noradrenaline), not actively bleeding and is unlikely to have significant ischaemic heart disease. Discussions with the family should weigh up the pros and cons of transfusion, and time devoted to hearing and clarifying their worries and concerns.
  • There is some evidence that transfusion is associated with increased rates of VAP and other infections.
  • Real risk of circulatory overload (up to 1 in 100 or Calman rating high), but probably less likely in this patient.
  • Risk of TRALI (said to be 1 in 5000 to 1 in 190000, or low to minimal
  • Anaphylaxis or non-fatal haemolytic reactions (very low)
  • In the event of a blood transfusion being administered, consent will be needed
  • It is also reasonable to wait
  • Set a trigger for transfusion (absolute Hb, clinical parameters) with the family)
  • A second opinion or even a substitute decision maker/legal opinion may need to be sought if clear harm or death is likely to result in the future without transfusion and consent is not likely to be forthcoming.

Non-transfusion strategies should be employed

  • Maximising nutrition
  • Minimising haemodilution
  • Consideration of haematinics / EPO
  • Minimising blood volume for tests by using paediatric tubes etc.
  • Haematology input if necessary.

Calman scale of risk useful in this context:

Negligible (less than 1 in a million or dying of lightning strike)

Minimal, Very low, Low (1 in a thousand to 1 in 10000 or dying in a road accident)

High (>1 in 1000)

Additional Examiners’ Comments:

Candidates were not expected to give this much detail and were given credit for valid points not included in the answer template

Discussion

I love it when they invite you to give less detail.

A "routine transfusion" in this setting is the transfusion which has a "numeric trigger" as opposed to a clinical indication (i.e. the patient is asymptomatic).

Rationale for some sort of strategy

  • Blood products are a scarce resource (and very expensive outside of an Australia-like socialised health care system)
  • Blood products are not without risk; specifically, there is a real nonzero risk of contracting a disabling infectious disease, or developing a life-threatening reaction.
  • Benefits of transfusion of stored red cells are unclear in this "borderline" population
  • Risk of transfusion needs to be weighed against benefit

Arguments in support of routine transfusion to a Hb of >70

  • Transfusion in the developed world is impressively safe.
  • Clinical features of anaemia may be insidious in onset, and it is possible to survive at a dramatically decreased haemoglobin - the argument is that this may not be the best quality of care for critically ill patients.
  • In the critically ill patients, the adverse effects of anaemia may be obscured by the ongoing critical illness.
  • Anaemia increases myocardial oxygen demand and reduced myocardial oxygen supply.
  • There are certain groups of critically ill patients for whom "routine" transfusion to a certain Hb level appears to be well supported by evidemce. These groups include patients with ongoing myocardial ischaemia and those undergoing ECMO.

Arguments against the routine transfusion to a Hb of >70

  • Anaemia with a poor systemic or myocardial oxygen supply/demand relationship is unlikely to be clinically silent (and nobody is arguing against transfusion for clinically significant anaemia)
  • There has never been any mortality benefit show for this practice in the critically ill population (outside of the acute coronary syndrome population)
  • Transfusion of stored cells contributes cells with a diminished oxygen carrying capacity
  • There are situations where exposure to foreign cells is to be avoided at all costs on medical grounds (eg. in patients being worked up for a transplant)

Practical approach to a questionably indicated transfusion

  • Need for consent is unquestioned (if the patient is exsanguinating, different story)
  • Involving the patient, ideally
  • Involving the family, as surrogates- in which case, validity of their involvement should be considered (eg. are these next of kin, or work friends?)
  • Cultural background needs to be considered (eg. Jehovah's Witness)
  • Age needs to be considered (underage? Covered by duty of care? The family may have little recourse, but the patient who is transfused against their will may be excommunicated from the cult).
  • If no cultural or ethical barriers, consider the blood bank may not supply the blood without an indication. Consider that "the haemoglobin's low" is not an indication. Will you manufacture an indication and lie, or will you engage with them on a theoretical level, talking about oxygen carrying capacity of blood and whatnot?

Alternatives to transfusion

Spahn et al (2013) have done an excellent review of this for  Lancet. In summary:

  • Transfuse something not quite blood, or less risky blood
    • Autologous transfusion (eg. pre-banked blood) - though usually the JWs do not go for this option
    • Blood surrogates (largely experimental)
  • Avoidance of blood loss
    • Advanced haemostasis measures intraoperatively, eg. topical haemostatic agents
    • Use of low volume blood tubes
    • Rationalisation of blood tests
  • Support of effected (or supra-normal) erythropoiesis
    • Good nutrition
    • Adequate micronutrients
    • Adequate haematinic vitamins
    • Avoidance of bone marrow toxins
    • Iron infusion
    • Erythropoietin

References

References

Goodnough, Lawrence T., Jerrold H. Levy, and Michael F. Murphy. "Concepts of blood transfusion in adults." The Lancet 381.9880 (2013): 1845-1854.

Spahn, Donat R., and Lawrence T. Goodnough. "Alternatives to blood transfusion." The Lancet 381.9880 (2013): 1855-1865.

There is also a rescinded document from the NHMRC (2001) which has been used to guide practice: Clinical Practice Guidelines on the Use of Blood Components.

To some extent this document has been superceded by the Australian and New Zealand Society of Blood Transfusion GUIDELINES FOR THE ADMINISTRATION OF BLOOD PRODUCTS.

The Patient Blood Management Guidelines from the National Blood Authority of Australia is another series of documents worth looking at - it contains several important modules which have been reviewed and which act as successors to the 2001 NHMRC guidelines.

Treleaven, Jennie, et al. "Guidelines on the use of irradiated blood components prepared by the British Committee for Standards in Haematology blood transfusion task force." British Journal of Haematology 152.1 (2011): 35-51.

Aoun, Elie, et al. "Transfusion‐associated GVHD: 10 years’ experience at the American University of Beirut—Medical Center." Transfusion 43.12 (2003): 1672-1676.

Heddle, Nancy M., and Morris A. Blajchman. "The leukodepletion of cellular blood products in the prevention of HLA-alloimmunization and refractoriness to allogeneic platelet transfusions [editorial]." Blood 85.3 (1995): 603-606.

Sharma, R. R., and Neelam Marwaha. "Leukoreduced blood components: Advantages and strategies for its implementation in developing countries."Asian journal of transfusion science 4.1 (2010): 3.

Dzik, Walter H. "Leukoreduction of blood components." Current opinion in hematology 9.6 (2002): 521-526.

Corwin, Howard L., and James P. AuBuchon. "Is leukoreduction of blood components for everyone?." JAMA 289.15 (2003): 1993-1995.

Blajchman, M. A. "The clinical benefits of the leukoreduction of blood products."Journal of Trauma-Injury, Infection, and Critical Care 60.6 (2006): S83-S90.

Rosenbaum, Lizabeth, et al. "The reintroduction of nonleukoreduced blood: would patients and clinicians agree?." Transfusion 51.12 (2011): 2739-2743.

Bilgin, Y. M., L. M. van de Watering, and A. Brand. "Clinical effects of leucoreduction of blood transfusions." Neth J Med 69.10 (2011): 441-450.

Australian Red Cross - Blood Service Policy on "The Age of Red Cells"

Hess, John R. "Red cell changes during storage.Transfusion and Apheresis Science 43.1 (2010): 51-59.

Bennett-Guerrero, Elliott, et al. "Evolution of adverse changes in stored RBCs."Proceedings of the National Academy of Sciences 104.43 (2007): 17063-17068.

Hébert, Paul C., et al. "A multicenter, randomized, controlled clinical trial of transfusion requirements in critical care." New England Journal of Medicine340.6 (1999): 409-417.

Carson, Jeffrey L., Paul A. Carless, and Paul C. Hébert. "Outcomes using lower vs higher hemoglobin thresholds for red blood cell transfusion." Jama 309.1 (2013): 83-84.

Lelubre, C., J. L. Vincent, and F. S. Taccone. "Red blood cell transfusion strategies in critically ill patients: lessons from recent randomized clinical studies." Minerva anestesiologica (2016).

Spahn, Donat R., and Lawrence T. Goodnough. "Alternatives to blood transfusion." The Lancet 381.9880 (2013): 1855-1865.