Retrograde Autologous Priming for Reducing Blood Transfusions

(TheRAPy Trial)

Recruiting at 3 trial locations

Overseen By Jessica Spence

Age: Any Age

Sex: Any

Trial Phase: Academic

Sponsor: Population Health Research Institute

Disqualifiers: Complete <=200 cases, <95% agreement

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Compensation: Varies

Number of Visits: Unknown

Duration: 12 periods of 4 weeks

4500 Participants Needed

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial tests two methods to prepare patients for heart surgery to determine which reduces the need for blood transfusions. One method uses the patient's own blood, known as retrograde autologous priming, while the other uses a fluid solution. The goal is to identify the better method for patients undergoing heart surgery with a heart-lung machine. The trial seeks participants scheduled for heart surgery involving a heart-lung machine at participating hospitals. As an unphased trial, it offers a unique opportunity to contribute to important research that could enhance surgical outcomes for future heart surgery patients.

Will I have to stop taking my current medications?

The trial information does not specify whether you need to stop taking your current medications. It's best to consult with the trial coordinators or your doctor for guidance.

What prior data suggests that retrograde autologous priming is safe for reducing blood transfusions?

Earlier studies have shown that retrograde autologous priming (RAP) is a well-tolerated procedure for patients undergoing heart surgery. Research indicates that using RAP does not significantly increase the risk of in-hospital death compared to not using it. One study found a death rate of 2.7% for those who used RAP and 3.8% for those who did not, indicating a small difference.

RAP is also considered safe and less invasive. It can reduce the need for blood transfusions, potentially lowering risks associated with transfusions, such as extended time on a ventilator. Overall, current findings suggest that RAP is safe for use in heart surgeries. ^{1 2 3 4 5}

Why are researchers excited about this trial?

Researchers are excited about retrograde autologous priming (RAP) during cardiac surgery because it could reduce the need for blood transfusions. Unlike traditional methods that rely on donated blood, RAP uses the patient's own blood to prime the heart-lung machine, which can minimize the risks associated with blood transfusions, such as immune reactions and infections. Additionally, RAP might enhance recovery times and reduce complications, making cardiac surgery safer and more efficient.

What evidence suggests that this trial's treatments could be effective for reducing blood transfusions in cardiac surgery?

This trial will compare Retrograde Autologous Priming (RAP) with Crystalloid priming during cardiac surgery. Studies have shown that RAP can reduce the need for blood transfusions during heart surgery. This technique uses a patient's own blood to prepare the heart-lung machine, decreasing the reliance on donor transfusions. Research indicates that RAP not only lowers the risk of transfusion but also reduces the chances of complications, such as prolonged breathing assistance after surgery. Some studies have noted that patients might leave the hospital sooner when RAP is used. Overall, RAP appears to be an effective method for conserving blood during heart surgeries. ^{3 6 7 8 9}

Who Is on the Research Team?

Jessica Spence, MD, PhD

Principal Investigator

Population Health Research Institute

Are You a Good Fit for This Trial?

This trial is for patients undergoing cardiac surgery with cardiopulmonary bypass at hospitals that do more than 200 such surgeries a year. The entire cardiovascular team must agree to follow the assigned priming policy throughout the trial.

Inclusion Criteria

I am having heart surgery with cardiopulmonary bypass at a participating hospital.

My hospital performs over 200 adult heart surgeries yearly and agrees to follow the trial's blood management policy.

Exclusion Criteria

Complete 200 or fewer cardiac surgical cases

Less than 95% of their cardiovascular surgery group agrees to manage patients according to either of the two policies

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

2-4 weeks

Treatment

Participants undergo cardiac surgery with either retrograde autologous priming or crystalloid priming

12 periods of 4 weeks

Follow-up

Participants are monitored for transfusion requirements and adherence to policies up to 72 hours after surgery

1 week

Data Collection

Data is collected about critical parameters affecting the design and implementation of the full-scale trial

6 months

What Are the Treatments Tested in This Trial?

Interventions

• Retrograde Autologous Priming

Trial Overview The study compares two methods of preparing the heart-lung machine used in surgery: retrograde autologous priming (RAP) and crystalloid priming, to see if RAP reduces the need for blood transfusions during cardiac surgery.

How Is the Trial Designed?

Group I: Retrograde autologous priming Experimental Treatment 1 Intervention

sites implement retrograde autologous priming (RAP) during cardiac surgery

Group II: Crystalloid priming Experimental Treatment 1 Intervention

sites implement crystalloid priming use during cardiac surgery

Who Is Running the Clinical Trial?

Population Health Research Institute

Lead Sponsor

Trials

165

Recruited

717,000+

Published Research Related to This Trial

In a study of 559 cardiac surgery patients, retrograde autologous priming (RAP) did not increase the risk of in-hospital mortality compared to a group that did not use RAP, indicating its safety as a blood conservation technique.

The use of RAP was associated with a significantly lower incidence of postoperative cardiac arrest (1 patient in the RAP group vs. 9 in the no-RAP group), suggesting a potential benefit in improving postoperative outcomes.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Retrograde autologous priming of the cardiopulmonary bypass circuit: safety and impact on postoperative outcomes. Murphy, GS., Szokol, JW., Nitsun, M., et al.[2006]

In a study of 545 cardiac surgical patients over 24 months, using retrograde autologous priming (RAP) during cardiopulmonary bypass did not significantly reduce the need for blood transfusions, with only a small, statistically insignificant decrease in patients receiving packed red blood cells (44% with RAP vs. 51% without).

Overall, the use of RAP as a blood conservation strategy did not demonstrate a clinically important benefit in reducing blood product use during cardiac surgeries, as no significant differences were found in the total units of packed red blood cells, platelets, or fresh frozen plasma transfused.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

The failure of retrograde autologous priming of the cardiopulmonary bypass circuit to reduce blood use after cardiac surgical procedures. Murphy, GS., Szokol, JW., Nitsun, M., et al.[2019]

In a study of 753 patients undergoing cardiac surgery, retrograde autologous priming (RAP) significantly reduced haemodilution and the need for blood transfusions, with a nadir haematocrit of 26.8% in the RAP group compared to 25.8% in controls.

RAP was associated with a lower transfusion frequency (26.1% vs 33.3%) and was found to be an effective strategy for minimizing transfusion rates during cardiopulmonary bypass, especially when the RAP volume was tailored to individual patient characteristics.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

The effect of retrograde autologous priming volume on haemodilution and transfusion requirements during cardiac surgery. Vandewiele, K., Bové, T., De Somer, FM., et al.[2021]

Retrograde autologous priming of the cardiopulmonary bypass circuit significantly reduces the number of patients receiving intraoperative packed red blood transfusions and the total number of transfusions during hospital stays, based on a meta-analysis of six trials involving adult cardiac surgery.

While retrograde autologous priming shows promise in reducing overall transfusion needs, it does not significantly decrease the number of units transfused during the surgery itself, indicating that its benefits may be more pronounced in the overall hospital context rather than intraoperatively.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Retrograde autologous priming and allogeneic blood transfusions: a meta-analysis. Saczkowski, R., Bernier, PL., Tchervenkov, CI., et al.[2017]

In a study of 100 patients undergoing coronary artery bypass grafting, retrograde autologous priming (RAP) significantly reduced the prime volume of the cardiopulmonary bypass system from 1,627 mL to 782 mL, leading to less haemodilution.

Patients in the RAP group experienced a higher lowest hematocrit level (26%) and a significantly lower rate of packed red blood cell transfusions (6%) compared to the NON-RAP group (26%), indicating that RAP is effective in minimizing blood loss during surgery.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Retrograde autologous priming reduces transfusion requirements in coronary artery bypass surgery. Severdija, EE., Heijmans, JH., Theunissen, M., et al.[2022]

In a study of 201 patients undergoing coronary artery bypass grafting (CABG), retrograde autologous priming (RAP) did not significantly reduce the need for packed red cell (PRC) or blood product transfusions during surgery, indicating that RAP may not be effective in minimizing transfusion requirements.

Factors such as CPB time, preoperative hemoglobin levels, and creatinine clearance were found to be more significant predictors of blood product transfusion than the use of RAP, suggesting that other clinical parameters play a more critical role in transfusion needs.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

The effect of retrograde autologous priming on intraoperative blood product transfusion in coronary artery bypass grafting. Nanjappa, A., Gill, J., Sadat, U., et al.[2015]

Retrograde autologous priming (RAP) significantly reduces the need for intraoperative allogeneic red cell transfusions in cardiac surgery, with a pooled odds ratio of 0.34 from 18 studies involving 4,664 patients.

RAP also decreases the overall incidence of hospital-wide red cell transfusions without increasing the risk of adverse events like acute kidney injury or stroke, suggesting it is a safe and effective strategy for minimizing transfusions during cardiac surgery.

NCBI (Pubmed)

pubmed.ncbi.nlm.nih.gov

Retrograde Autologous Priming in Cardiac Surgery: Results From a Systematic Review and Meta-analysis. Hensley, NB., Gyi, R., Zorrilla-Vaca, A., et al.[2021]

Citations

1. pmc.ncbi.nlm.nih.gov pmc.ncbi.nlm.nih.gov/articles/PMC4165246/

Assessing the effectiveness of retrograde autologous ... This study confirmed that RAP is likely to be safe but did not influence postoperative blood transfusion rates. However, there was a shorter in-hospital stay in ...

2. sciencedirect.com sciencedirect.com/science/article/pii/S2666273625000853

Does retrograde autologous priming during coronary artery ... Use of retrograde autologous priming may result in fewer transfusions and thus potentially prevent transfusion-associated risks such as prolonged ventilation.

3. pubmed.ncbi.nlm.nih.gov pubmed.ncbi.nlm.nih.gov/34417595/

Retrograde autologous priming in cardiac surgery This meta-analysis supports the use of RAP as a blood conservation strategy since its use during cardiopulmonary bypass appears to reduce transfusion ...

4. journals.lww.com journals.lww.com/md-journal/fulltext/2024/11150/factors_impacting_the_efficacy_of_the_retrograde.60.aspx

Factors impacting the efficacy of the retrograde autologous ... Our study demonstrated that RAP technique reduced the need for blood transfusion during the intraoperative and postoperative periods and resulted less drainage ...

5. aats.org aats.org/resources/abstract.pdf?abstract=2058974

Retrograde Autologous Priming Reduces Blood ... On risk-adjusted analysis, RAP was found to significantly reduce the risk of postoperative blood transfusion (OR=0.54 [0.35-0.83], p=0<01) and prolonged ...

6. pubmed.ncbi.nlm.nih.gov pubmed.ncbi.nlm.nih.gov/16616653/

Retrograde autologous priming of the cardiopulmonary ... Measurements and main results: In-hospital mortality was not significantly different between the RAP group (2.7%) and the no-RAP group (3.8%, p = 0.636). The ...

7. sciencedirect.com sciencedirect.com/science/article/abs/pii/S1053077005001527

Retrograde Autologous Priming of the Cardiopulmonary ... Measurements and Main Results: In-hospital mortality was not significantly different between the RAP group (2.7%) and the no-RAP group (3.8%, p = 0.636). The ...

8. cardiothoracicsurgery.biomedcentral.com cardiothoracicsurgery.biomedcentral.com/articles/10.1186/s13019-018-0739-0

Positive impact of retrograde autologous priming in adult ... Retrograde autologous priming is a safe and less invasive procedure which achieves clear benefits for adult cardiac surgery patients.

9. jtcvsopen.org jtcvsopen.org/article/S2666-2736(25)00085-3/fulltext

Does retrograde autologous priming during coronary artery ... Use of retrograde autologous priming may result in fewer transfusions and thus potentially prevent transfusion-associated risks such as prolonged ventilation.