In the June 2016 issue of CMAJ, Dr. Hebert published an article, Survival Without Transfusion Is Possible but Not Recommended for All, that critiques Dr. Aryeh Shander's research study Outcomes of Protocol-Driven Care of Critically Ill Severely Anemic Patients for Whom Blood Transfusion Is Not an Option, published in Critical Care Medicine 2016.
Dr. Aryeh Shander is familiar to anyone who follows the blood management and the bloodless surgery industry. Shander is the "face" of blood management worldwide. I have spoke of him many times on this forum and elsewhere.
But who is Dr. Paul Hebert? What qualifies him to critique Shander's research?
Dr. Paul C. Hébert is Head of Department of Medicine, a scientist and a Critical Care Physician at The Centre Hospitalier de l’Université de Montreal. He is also Chair of the Canadian Critical Care Trials Group. During his 14 years on Faculty at the University of Ottawa, Dr. Hébert established the Clinical Epidemiology Program at the General Campus of The Ottawa Hospital (1998) and the University of Ottawa Centre for Transfusion Research. Dr. Hébert’s research interests center on the examination of transfusion practice, including the use of alternatives to transfusion, blood conservation, resuscitation fluids, as well as on cardiac resuscitation and trauma research. Dr. Hébert has undertaken more than 30 research projects with a focus on transfusion practice and bleeding control. To date, he has published more than 250 articles and he obtained a large number of peer-reviewed grants (with a combined value in excess of $40 millions).
Dr.Paul Hebert was also the editor-in-chief of the Canadian Medical Association Journal (CMAJ), Canada’s leading peer-reviewed medical journal from 2007-2011.
The objective of Shander et al's study was "to compare the outcomes of severely anemic criticallyill patients for whom transfusion is not an option (“bloodless” patients) with transfused patients." To do this, "one hundred seventy-eight bloodless and 441 transfused consecutive severely anemic, critically ill patients, admitted between May 1996 and April 2011", were selected and compared.
Shander et al concluded this:
Overall risk of mortality in severely anemic critically ill bloodless patients appeared to be comparable with transfused patients, albeit the latter group had older age and higher Acute Physiology and Chronic Health Evaluation II score. Use of a protocol to manage anemia in these patients in a center with established patient blood management and bloodless medicine and surgery programs is feasible and likely to contribute to improved outcome, whereas more studies are needed to better delineate the impact of such programs.
Is this a valid conclusion? That "...Overall risk of mortality in severely anemic critically ill bloodless patients appeared to be comparable with transfused patients"? Dr. Hebert disagrees and he discusses the problem with Shander's methodology:
The authors made a number of inferences regarding outcomes
from the transfused and untransfused population of
critically ill patients. Overall, these populations were quite different
at baseline; they were younger, less severely ill, and more
often admitted to ICU for postoperative care. So comparing
rates of death without some form of statistical adjustment
would not be fruitful. There is, however, no guarantee that any
form of statistical manipulation will provide an unbiased and
Next, Hebert tells us how Shader et al approached this statistical problem:
Shander et al (1) opted to use a method of analysis called
propensity analysis to improve the matching between groups.
The choice of the many propensity analyses is not created
equal and may not be superior to other methods in this regard
(2). Using this approach, they ended up selecting a group of
patients who did not develop extreme anemia.
So what did happen with the use of the propensity matching
technique? The technique invariably removed approximately
half the deaths. The most severely anemic patients
were removed from the analysis by design. Therefore, mortality
rates were drastically decreased in both groups but
more so in the bloodless group. By doing so, both groups
ended up looking comparable with average hemoglobin
concentrations that were not much lower than a standard
Dr. Hebert identifies the underlying problem with this type of study:
At the outset, it is not possible to produce meaningful comparisons
between a group of patients who will not receive any
blood products to a group who does. This is because risks
increase as hemoglobin concentrations drop. Therefore, risks
of death attributed to anemia in the bloodless group will always
be higher than in a transfused cohort. There is no ethically
acceptable manner to allow the transfused group to develop
extreme anemia prior to being transfused.
Dr. Hebert discusses the one redeeming feature of Shander's study: it shows how risk of death increases dramatically once a certain level of hemoglobin deficiency is reached:
...mortality rates with hemoglobin
concentrations below 3 g/dL is over 55% and drop precipitously
to somewhere around 28% when hemoglobin concentrations
are between 3.1 and 4 g/dL. Anemia in the bloodless group was
thought to be the primary cause of death in 36% of all deaths.
Dr. Hebert then goes on to identify what information was left out in Shander's study, that could have been useful to include:
Additional information would have been useful to readers. A
figure of all patients divided by transfused and not transfused
would have also been very useful. Also, it would have been interesting
to examine whether such severe anemia also increases
other risks: for example, functional outcomes from prolonged
And why would this information be useful?
These rates, albeit from a single center with extensive
experience with extreme anemia, provide some information to
provide families of critically ill patients who refuse blood.
In conclusion, Dr. Hebert addresses the impact of this failed study on the families who are faced with making decisions about the care of a patient with severe anemia:
In summary, these observations demonstrate that acute
severe anemia is lethal. It directly contributes to the death
when hemoglobin concentrations fall below 3 g/dL. Furthermore,
from the data provided, we would be unable to
provide meaningful comparisons of risks of death comparing
transfused with nontransfused patients to families when
lowest measured hemoglobin concentrations were between
3 and 7 g/dL.
Far too often, JW patients approach medical problems with erroneous and incomplete information that has been fed to them by the WT. Doctors are then left with the task of trying to give those patients reliable and accurate information - a task that is often insurmountable.
Dr. Paul Hebert has shown why Dr. Aryeh Shader's research is shoddy and incomplete. Shander's study fails the sniff test and the reader is left wondering why and how research like this comes about. Sponsorship is the very first place that a person can get some clues.
Dr. Hebert's article has this attached to it:
The author has disclosed that he does not have any potential conflicts of
Aryeh Shander's study has this attached to it:
Dr. Shander received funding from Bayer, Luitpold, and Masimo; has been
a consultant or speaker with honorarium for or received research support
from Bayer, Luitpold, Masimo, Novartis, Novo Nordisk, OrthoBiotech,
Pfizer, Masimo, and Zymogenetics; and is a founding member of the Society
for the Advancement of Blood Management (SABM).
Aryeh Shander - a founding member of the Society for the Advancement of Blood Management. The society that sets the standards for blood management. The society that was founded along with members of the Hospital Liaison Committees of the Watchtower Society.
Dr. Shander - the "face" of blood management. The hero of bloodless surgery. The co-author of the seminal textbook used to educate blood management professionals - co-authored with a German JW doctor - Dr. Petra Seeber.
Dr. Shander - the spokesperson for STORMACT.
Dr. Shander - the doctor who went to Russia to promote blood management with Sherri Ozawa, the JW blood management 'specialist'.
Dr. Shander - a researcher who manipulates data to get the results he needs in order to promote bloodless procedures
It will be interesting to see if Shander's latest published research get presented at upcoming professional seminars and cited in support of bloodless procedures. I wonder how many citations Shander's shoddy research will get within the blood management world.
Much thanks goes out to Dr. Paul Hebert who has taken the time to expose researchers like Aryeh Shander who manipulate data to get the results they want.
*note - if anyone is having trouble accessing Dr. Hebert's article and Shander's research study...I am pretty sure Wifibandit will be able to help you out