Research Group on Blood Transfusion

 1.1 Red Blood Cell Transfusion-Associated Respiratory Complications (TARC) in Critically Ill Children.

Definitions of transfusion-associated respiratory complications are too restrictive for the pediatric population. This multicenter cross-sectional study will allow us to characterize risk factors of TARC in order to detect them earlier and prevent their occurence, evaluate all TARC in PICU patients and determine the epidemiology and clinical impact of TARC in the population studied.

1.2 Risk Factors Associated with Transfusion-Associated Circulatory Overload (TACO) Onset: Cases as Reported to the Blood Monitoring System in Quebec

TACO is a major cause of transfusion-associated fatalities. Risk factors associated with TACO are not well characterized. This multicenter prospective pilot study is based on TACO cases reported by the transfusion safety officers (TSO). It will characterize the cases of TACO in order to identify patients at risk of developing this complication and also identify medical and transfusion practices that may result in TACO occurence. This project may have an impact on the cost associated with hospital stay and acuity of care.

1.3 TACO Risks and Post-Transfusion Dyspnea in Patients Admitted with an Elevated BNP or NT-proBNP Level

Biomarkers associated with a TACO such as BNP (Brain Natriuretic Peptide) or NT-proBNP is not well identified. This retrospective study will determine the incidence of TACO and post-transfusion dyspnea among patients admitted to hospital with elevated BNP or NT-proBNP. The results of this study will allow us to determine if biomarkers can be used as a diagnostic tool and to know if BNP may be of some interest for the management of TACO.

1.4 Infectious Disease: Epstein - Barr virus (HHV-4) and Other Human Herpes Viruses (HHV-6/7)

Although the risk of post-transfusion-transmitted HHV-4 or HHV-6/7 infection has become extremly rare, the risk of infectious disease transmission for which testing is not done continues to be a major concern. This prevalence study will allow us to analyze the risks of transmitting untested post-transfusion infections.

2.1 Epidemiology of Blood Transfusion in Quebec

Information on the epidemiology of blood transfusion is scarce in the literature. It mostly addresses RBC transfusion and is not population - based. The only published Canadian study was a cross-sectional study conducted in the early1990s.

In a pilot study that was completed within the previous program, we identified patients who received blood units in three Quebec hospitals and created a database for these patients. We aim to apply the same procedure to all Quebec hospitals for the year 2008. This multicenter retrospective study will allow us to identify possible improvements in the use of blood (inappropriate transfusions). This would be an asset to forecast future needs in terms of blood supply and to help in mathematical models that address emerging pathogens in the blood supply by identifying the proportion of the population that is transfused (by sex and specific age group).

2.2 Post-Transfusion Survival in the Province of Quebec

Information on post-transfusion survival is important for decision-makers and is an essential part of cost-benefit analyses in the transfusion decision-making process. Data on post-transfusion survival are limited. This multicenter project will allow us to identify a number of risk factors, which could lead to modifications in the transfusion decision-making process.

2.3.1 Age of Blood in Children in Pediatric Intensive care Units (ABC-PICU)

The randomized clinical study ABC PICU represents an important challenge for the management of blood bank inventories. The aim of the preparatory phase of the randomized clinical trial will allow us to verify the availability of red blood cell units with appropriate storage times. In addition, it is essential to ensure the participation of blood banks through education and by conducting a simulated management of 1-2 patients for some sites in order to solve possible system’s issues. This preparatory phase will serve in part to evaluate feasibility and optimal operation at participating sites before proceeding with the randomized clinical trial.

2.3.2 Length of storage of Transfused Packed Red Blood Cells in the Province of Quebec

Current policy is to first issue the oldest blood units available. However, there is no data on the potential impact of this policy on managing inventories and potential wastage of blood product. This multicenter project follows a pilot study previously conducted. The study will allow us to know the length of storage of transfused RBC units in Quebec and complete studies on the inventory and the economic impact that could have a policy advocating transfusion of fresh RBC units in critically ill patients.

2.4 Goal - Directed Red Blood Cell Transfusion Therapy

A number of parameters may be considered as markers that can serve as a guide when transfusion is considered. Currently, however, there is no consensus on the markers that should be selected. The study methodology will consist of identifying markers, determining the best ones and validating their selection. We expect to find that some systemic or regional oxygenation markers may be useful in guiding transfusion therapy in critically ill children. This may lead to a consensus on useful parameters.

2.5 Decision-Making in Cardiac Surgery in the Thromboelastograph Era (TEG)

TEG device is used to evaluate coagulation capacity. It seems that the use of TEGs leads to a decrease in the use of blood products. However, we are not able to determine whether the decrease is due to better results obtained through TEGs or the introduction of a new analysis technique. This descriptive retrospective study will focus on the types and numbers of transfused products in relation to an analysis obtained using a TEG device. We expect to find that TEG may indeed help practitioners in their decision-making process about transfusion prescription.

Lack or lag of knowledge application is considered an important problem by the National Institutes of Health (NIH) and the Canadian Institutes of Health Research (CIHR). Data from the USA and the Netherlands suggest that about 30-40% of patients do not receive care according to present scientific evidence. It has been stated that “the most cost-effective opportunity to improve patient outcomes will probably not come from novel therapies, but from discovering how to deliver therapies that are known to be effective.” We now know that barriers to knowledge transfer can come from caregivers as well as from patients themselves. The nature of these barriers can be scientific and can be overcome by good research. They can be attribuable to administrative problems like lack of leadership or unprotocolized treatment administration. However, there is also evidence that these barriers can originate from less rational causes, like social, cultural or religious influence. An anthropological study using qualitative methods is a good way to identify such barriers. To date, no study has been done on the anthropology of transfusion medicine from the perspective of the recipients and/or their families or caregivers.

3.1 Barriers from Caregivers to Implementation of Guidelines on Red Blood Cell Transfusion in Pediatric Intensive Care Units

The aim of this qualitative observational study, based on structured interviews, is to characterize the real determinants and the organizational structure of the decision-making process used by physicians who prescribe red blood cell transfusions.

We expect to note that the most important determinants in the decision to transfuse blood are personal beliefs rather than patient characteristics or available scientific evidence.

3.2 Beliefs and Perceptions of Transfusion Recipients and their Families

This qualitative observational study based on structured interviews will allow us to determine concerns that may become barriers to red blood cell transfusion in receivers and/or in their families, and to find ways to help receivers undego a better experience while being transfused.

We expect to find that most concerns of RBC transfusion recipients are not related to scientific questions like transfusion-transmitted infectious diseases, but rather to social, cultural or religious considerations as well as patient/family relationship and modes of communication.

3.3 Transfusion of Red Blood Cells in Pediatric Intensive Care Units: Evidence-Based Recommendations

We will write guidelines concerning the methods of transfusion in pediatrics. These guidelines will be created during a consensus conference based on existing evidence.