Healthy VolunteersPhase 2INOBANCT00838331
Adverse Effects of RBC Transfusions: A Unifying Hypothesis
A Phase 2 study testing Fresh blood and Aged blood in people with Healthy Volunteers, run by Emory University at 1 site in United States.
Trial summary
Transfusion of red blood cells is often used in critically ill patients with low red blood cell counts to prevent disease progression and death. Recent studies suggest that the use of "aged" versus "fresh" red blood cells are associated with worse clinical outcomes. Read more about this study
- Who is it for?
- Ages 21 to 80 yearsHealthy volunteers can take part
- Conditions the study is for
- Healthy Volunteers
- What is being tested?
- Fresh blood and Aged blood
- Could I receive a placebo?
- No, everyone receives an active treatment
- How many people
- 24 participants
- Where
- 1 siteUnited States
- Study dates
- Apr 2009to Oct 2013
- Phase
- Phase 2
- Are there results?
- Yes, posted in the registrySummary in the doctors' view
Key requirements
Who can take part, as listed by the sponsor. Only the study team can confirm whether you are eligible, so take this list to your doctor.
- Ages 21 to 80 years
- All sexes
- Healthy volunteers accepted
- Adult, Older adult
Who may be able to join
- Healthy male or female volunteers (age 21-60 years)
- Must meet guidelines for blood donors including:
- standard blood donor history questionnaire
- body weight of at least 110 lbs
- hemoglobin concentration of at least 12.5 gm/dL
- body temperature of no more than 99.5 oF
Show all 11Show fewer
- pulse of 50-100 bpm
- blood pressure < 180/100
- test negative for the standard battery of blood donor screening tests (anti-HIV, HIV RNA, anti-HCV, HCV RNA, HBsAg, anti-HBc, anti-HTLV-I/II, and WNV RNA)
- Aim 1:
- Healthy male or female volunteers (age 21-80 years)
Who cannot join
- Failure to pass the blood donor history questionnaire
- Positive results on the standard battery of blood donor screening tests
- Failure to meet criteria for donation
- Aim 2:
- Presence of intercurrent illness or other chronic diseases
- Renal failure (creatinine>1.4 mg/dl)
Show all 15Show fewer
- Pregnancy
- Allergies to aspirin
- Bleeding disorders
- Uncontrolled hypertension with BP > 180 mmHg systolic and > 120 mmHg diastolic
- Acute infection in previous 4 weeks
- History of substance abuse
- Liver failure (Liver enzymes >2x normal)
- Inability to give informed consent
- Inability to return to Emory for follow-up
Trial locations and contacts
1 site in 1 country.
About this study
Transfusion of red blood cells is often used in critically ill patients with low red blood cell counts to prevent disease progression and death. Recent studies suggest that the use of "aged" versus "fresh" red blood cells are associated with worse clinical outcomes. There is evidence that red blood cells work with the cells lining our blood vessels to produce a variety of substances that normally cause arteries to relax and increase blood supply. Two of these substances are called nitric oxide (NO) and endothelium-derived hyperpolarizing factor (EDHF). The investigators are trying to determine the nature of these substances in human beings when they are transfused "aged" versus "fresh" red blood cells. It is their thought that "aged" red blood cells have less of the substances (NO and EDHF) that naturally relax our arteries and further changes the blood supply. One way to determine this is to transfuse a subject's own "aged" and "fresh" red blood cells and inject substances such as L-NMMA (L-NG monomethyl arginine) and TEA (tetraethylammonium chloride), which block the production of NO and EDHF respectively, and then, study what happens to the blood flow.
There is evidence that red blood cells produce NO, which normally causes arteries to relax and increase blood supply. The investigators will try to determine the nature of NO in red blood cells and whether the amount of this substance is altered because of different blood processing and storage techniques. It is their thought that "aged" red blood cells have less NO that naturally relaxes our arteries and further changes the blood supply. This study is designed to determine the most ideal way of storing and processing blood.
Read the detailed description
Transfusion of red blood cells (RBCs) is often effective at preventing morbidity and mortality in anemic patients. In contrast, recent studies indicate that some RBC components may have functional defects ("RBC storage lesions") that actually cause morbidity and mortality when transfused. For example, patients transfused with RBCs stored >14 days have statistically worse outcomes than those receiving "fresher" RBC units. In addition to the age of stored RBCs, the volume transfused may be important. The TRICC study showed that specific patients whose transfusions were limited by a restrictive trigger (RBCs transfusions only when hemoglobin [Hb] < 7 g/dL) had significantly better outcomes than those transfused with a more liberal trigger ([Hb] < 10 g/dL Hb). This finding has been particularly difficult to understand since conventional wisdom suggests that an elevated [Hb] should be beneficial because it supports increased O2 delivery. Recipient-specific factors may also contribute to the occurrence of these adverse events. Unfortunately, these events have been difficult to investigate because up to now they have existed only as "statistical occurrences" of increased morbidity and mortality in large data sets. There are currently no clinical or laboratory methods to detect or study them in individual patients.
The microcirculation is composed of a continuum of small vessels including small arterioles, capillaries, and post-capillary venules. The microcirculation represents an actively-adjusting vascular circuit that matches blood flow (and O2 delivery) to local tissue oxygen demands. While the physiologic mechanisms that match O2 delivery to local requirements are incompletely understood, endothelium-derived nitric oxide (NO) clearly plays an important role. Interestingly, recent work has revealed that in addition to transporting O2 and CO2, the RBC also controls local NO concentrations and thus may also play a surprisingly important role in regulating blood flow in the microcirculation.
Herein, the investigators bring together previously unconnected data to propose a unifying hypothesis, centered on insufficient NO bioavailability (INOBA), to explain the increased morbidity and mortality observed in some patients following RBC transfusion. In this model, variables associated with RBC units (storage time; 2,3-DPG concentration) and transfusion recipients (endothelial dysfunction; hematocrit [Hct]) collectively lead to changes in NO levels in vascular beds. Under certain circumstances, these variables are "aligned" such that NO concentrations are markedly reduced, leading to vasoconstriction, decreased local blood flow and insufficient O2 delivery to end organs. Under these circumstances, the likelihood of morbidity and mortality escalates. The INOBA hypothesis is attractive because of its explanatory power and because it leads to a number of readily testable predictions, which will be investigated in the following aims:
Aim 1: To investigate the effects of blood processing and storage (using standard FDA-approved conditions) on NO production and scavenging by human RBCs/Hb in vitro. Using sensitive biochemical assays (electron spin resonance [ESR]) and a rat aortic ring in vitro bioassay, the investigators will test the effects of RBC storage time, leukoreduction, and irradiation on NO synthesis and/or scavenging by intact RBCs and free Hb. Modifications such as washing and rejuvenation will be investigated as possible approaches to correct abnormalities in NO bioavailability.
Aim 2: To transfuse healthy volunteers and investigate the effects of storage-related RBC changes on blood flow, tissue oxygenation, and biomarkers of cardiovascular function. The investigators will determine whether RBCs prepared and stored under conditions that alter NO bioavailability in vitro (Aim 1) inhibit NO-mediated vasodilation, reduce tissue perfusion, and decrease tissue O2 delivery in healthy transfusion recipients in vivo. The role of 2,3-DPG depletion as well as exercise-induced O2 demand will also be investigated with these specialized experimental systems.
- Conditions
- Healthy Volunteers
- Being tested
- Fresh blood, Aged blood
- Keywords
- Blood Transfusions
What participants receive
What participants receive. In a randomised study each person is assigned to one group by chance.
Fresh bloodBiological
For fresh transfusions, a whole blood unit will be drawn from volunteers, processed, and then reinfused on the same day during the study. For impaired and repaired transfusions, the volunteers will be brought to the blood bank to donate; then, after processing and the appropriate length of storage (eg, 28 days), they will return for the FBF studies. Since recipients of fresh transfusions are relatively anemic after donation and before reinfusion, recipients of impaired/repaired transfusions should also be mildly anemic for the study. Thus, they will donate another whole blood unit prior to beginning the study course, they will be transfused with their stored unit during the study, and then the autologous unit collected at the beginning of the day will be reinfused at the end of the day after the study is complete.
Aged bloodBiological
In a separate aim, the FMD assay will be used to investigate NO-mediated vasodilation in patients with CVD who are receiving transfusions. Over 60% of blood orders for cardiology patients at Emory are for 2 units or more. Therefore, when a 2-unit order is placed on a consented patient, they will be issued both fresh (< 7 days) and impaired (> 28 days) compatible units from inventory. Prior to starting transfusions, the patient will be randomized to either receive the fresh or the older unit first. All RBC units will be ACD/AS1. Units will also be leukoreduced and/or irradiated, if either of those modifications were found to impair NO bioavailability in prior studies. If washing or rejuvenation were found to be successful in significantly "repairing" NO bioavailability in previous aims, some patients may also receive impaired and repaired (> 28 days; washed or rejuvenated) RBC transfusions.
| Study group | Role | What they receive |
|---|---|---|
| Fresh blood, then aged blood | Experimental | Not described Receives: Biological: Fresh blood; Biological: Aged blood |
What is being measured
The primary outcome is the main question the study is designed to answer.
The Effects of Storage-related RBC Changes on Acetylcholine-stimulated (NO-mediated) Forearm Blood Flow.
The primary outcome measures are changes in forearm blood flow (FBF) in recipients of fresh or stored RBC transfusions in response to acetylcholine. Secondary measures include changes in FBF with acetylcholine with or without L-NMMA, and changes in FBF with forearm exercise. In addition, flow mediated dilation (FMD) measurements will also be used to assess changes in brachial artery diameter before and after fresh vs aged RBC transfusions.
Measured: 5 years
Timeline
From the start of the study to its completion; the mark is today. Estimated dates are the sponsor’s plan.
- First posted6 Feb 2009 (estimated)
- Study startApr 2009
- Primary completionMay 2013
- Study completionOct 2013
Resources
- Official record on ClinicalTrials.govThe registry entry this page is built from, with its full change history.
- Posted resultsParticipant flow, outcome measures and adverse events reported by the sponsor.
- Publications (2)Papers the sponsor has linked to this study.
- Other trials for Healthy VolunteersStudies of the same condition, open and under way.
- More trials run by Emory UniversityThe sponsor's other registered studies.
- What the trial phases meanHow a treatment moves from first tests in people to approval.
More details
For doctors and researchers: how the study is designed, who runs it, and its registry IDs.
Study design
- Study type
- Interventional
- Phase
- Phase 2
- Primary purpose
- Treatment
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Enrolment
- 24 participants (actual)
Sponsor and investigators
- Lead sponsor
- Emory University
- Sponsor type
- University, hospital or other
- Responsible party
- Principal investigator, John D Roback, Emory University
- Investigators
- Arshed A Quyyumi, MD, Principal investigator, Emory UniversityJohn Roback, MD, PhD, Principal investigator, Emory University
IDs, dates and publications
- ClinicalTrials.gov ID
- NCT00838331
- Sponsor's protocol ID
- IRB00015316
- Acronym
- INOBA
- Status last verified
- Mar 2015
- First submitted
- 5 Feb 2009
- Last updated
- 6 Mar 2015
- Results posted
- Yes, on ClinicalTrials.gov
- Data monitoring committee
- Yes
Publications
Hayek SS, Neuman R, Ashraf K, Sher S, Newman JL, Karatela S, Roback JD, Quyyumi AA. Effect of storage-aged red blood cell transfusions on endothelial function in healthy subjects. Transfusion. 2015 Nov;55(11):2768-70. doi: 10.1111/trf.13276. No abstract available.
PubMed 26559401Neuman R, Hayek S, Rahman A, Poole JC, Menon V, Sher S, Newman JL, Karatela S, Polhemus D, Lefer DJ, De Staercke C, Hooper C, Quyyumi AA, Roback JD. Effects of storage-aged red blood cell transfusions on endothelial function in hospitalized patients. Transfusion. 2015 Apr;55(4):782-90. doi: 10.1111/trf.12919. Epub 2014 Nov 13.
PubMed 25393772
Study at a glance
From the registry record, last updated by the sponsor on 6 Mar 2015. Recruitment status is as the sponsor reported it: confirm with the study team.
- Official title
- Adverse Effects of RBC Transfusions: A Unifying Hypothesis
- ClinicalTrials.gov ID
- NCT00838331
- Acronym / sponsor ID
- INOBA / IRB00015316
- Conditions
- Healthy Volunteers
- Keywords
- Blood Transfusions
- Phase
- Phase 2
- Study type
- Interventional
- Recruitment status
- Completed
- Enrolment
- 24 participants (actual)
- Lead sponsor
- Emory UniversityUniversity, hospital or other
- Study start
- Apr 2009
- Primary completion
- May 2013 (actual)
- Study completion
- Oct 2013 (actual)
- First posted
- 6 Feb 2009 (estimated)
- Results
- Posted 6 Mar 2015
Clinical summary
The research question as the sponsor registered it. This describes what the study plans to test, not what it found.
Transfusion of red blood cells is often used in critically ill patients with low red blood cell counts to prevent disease progression and death. Recent studies suggest that the use of "aged" versus "fresh" red blood cells are associated with worse clinical outcomes. There is evidence that red blood cells work with the cells lining our blood vessels to produce a variety of substances that normally cause arteries to relax and increase blood supply. Two of these substances are called nitric oxide (NO) and endothelium-derived hyperpolarizing factor (EDHF). The investigators are trying to determine the nature of these substances in human beings when they are transfused "aged" versus "fresh" red blood cells. It is their thought that "aged" red blood cells have less of the substances (NO and EDHF) that naturally relax our arteries and further changes the blood supply. One way to determine this is to transfuse a subject's own "aged" and "fresh" red blood cells and inject substances such as L-NMMA (L-NG monomethyl arginine) and TEA (tetraethylammonium chloride), which block the production of NO and EDHF respectively, and then, study what happens to the blood flow.
There is evidence that red blood cells produce NO, which normally causes arteries to relax and increase blood supply. The investigators will try to determine the nature of NO in red blood cells and whether the amount of this substance is altered because of different blood processing and storage techniques. It is their thought that "aged" red blood cells have less NO that naturally relaxes our arteries and further changes the blood supply. This study is designed to determine the most ideal way of storing and processing blood.
Detailed description
Transfusion of red blood cells (RBCs) is often effective at preventing morbidity and mortality in anemic patients. In contrast, recent studies indicate that some RBC components may have functional defects ("RBC storage lesions") that actually cause morbidity and mortality when transfused. For example, patients transfused with RBCs stored >14 days have statistically worse outcomes than those receiving "fresher" RBC units. In addition to the age of stored RBCs, the volume transfused may be important. The TRICC study showed that specific patients whose transfusions were limited by a restrictive trigger (RBCs transfusions only when hemoglobin [Hb] < 7 g/dL) had significantly better outcomes than those transfused with a more liberal trigger ([Hb] < 10 g/dL Hb). This finding has been particularly difficult to understand since conventional wisdom suggests that an elevated [Hb] should be beneficial because it supports increased O2 delivery. Recipient-specific factors may also contribute to the occurrence of these adverse events. Unfortunately, these events have been difficult to investigate because up to now they have existed only as "statistical occurrences" of increased morbidity and mortality in large data sets. There are currently no clinical or laboratory methods to detect or study them in individual patients.
The microcirculation is composed of a continuum of small vessels including small arterioles, capillaries, and post-capillary venules. The microcirculation represents an actively-adjusting vascular circuit that matches blood flow (and O2 delivery) to local tissue oxygen demands. While the physiologic mechanisms that match O2 delivery to local requirements are incompletely understood, endothelium-derived nitric oxide (NO) clearly plays an important role. Interestingly, recent work has revealed that in addition to transporting O2 and CO2, the RBC also controls local NO concentrations and thus may also play a surprisingly important role in regulating blood flow in the microcirculation.
Herein, the investigators bring together previously unconnected data to propose a unifying hypothesis, centered on insufficient NO bioavailability (INOBA), to explain the increased morbidity and mortality observed in some patients following RBC transfusion. In this model, variables associated with RBC units (storage time; 2,3-DPG concentration) and transfusion recipients (endothelial dysfunction; hematocrit [Hct]) collectively lead to changes in NO levels in vascular beds. Under certain circumstances, these variables are "aligned" such that NO concentrations are markedly reduced, leading to vasoconstriction, decreased local blood flow and insufficient O2 delivery to end organs. Under these circumstances, the likelihood of morbidity and mortality escalates. The INOBA hypothesis is attractive because of its explanatory power and because it leads to a number of readily testable predictions, which will be investigated in the following aims:
Aim 1: To investigate the effects of blood processing and storage (using standard FDA-approved conditions) on NO production and scavenging by human RBCs/Hb in vitro. Using sensitive biochemical assays (electron spin resonance [ESR]) and a rat aortic ring in vitro bioassay, the investigators will test the effects of RBC storage time, leukoreduction, and irradiation on NO synthesis and/or scavenging by intact RBCs and free Hb. Modifications such as washing and rejuvenation will be investigated as possible approaches to correct abnormalities in NO bioavailability.
Aim 2: To transfuse healthy volunteers and investigate the effects of storage-related RBC changes on blood flow, tissue oxygenation, and biomarkers of cardiovascular function. The investigators will determine whether RBCs prepared and stored under conditions that alter NO bioavailability in vitro (Aim 1) inhibit NO-mediated vasodilation, reduce tissue perfusion, and decrease tissue O2 delivery in healthy transfusion recipients in vivo. The role of 2,3-DPG depletion as well as exercise-induced O2 demand will also be investigated with these specialized experimental systems.
Study design
- Primary purpose
- Treatment
- Allocation
- Not applicable
- Intervention model
- Single group
- Masking
- None (open label)
- Number of arms
- 1
| Arm | Type | Receives |
|---|---|---|
| Fresh blood, then aged blood | Experimental | Biological: Fresh blood, Biological: Aged blood |
Who may qualify
- Ages
- 21 to 80 years
- Sex
- All
- Healthy volunteers
- Accepted
- Age groups
- Adult, Older adult
Key inclusion criteria (11 listed)
- Healthy male or female volunteers (age 21-60 years)
- standard blood donor history questionnaire
- body weight of at least 110 lbs
- hemoglobin concentration of at least 12.5 gm/dL
- body temperature of no more than 99.5 oF
Key exclusion criteria (15 listed)
- Failure to pass the blood donor history questionnaire
- Positive results on the standard battery of blood donor screening tests
- Failure to meet criteria for donation
- Presence of intercurrent illness or other chronic diseases
- Renal failure (creatinine>1.4 mg/dl)
Eligibility is decided by the study team after screening; this overview does not establish that a patient qualifies. Full inclusion and exclusion criteria.
Interventions
| Intervention | Type | Arms |
|---|---|---|
| Fresh bloodFor fresh transfusions, a whole blood unit will be drawn from volunteers, processed, and then reinfused on the same day during the study. For impaired and repaired transfusions, the volunteers will be brought to the blood bank to donate; then, after processing and the appropriate length of storage (eg, 28 days), they will return for the FBF studies. Since recipients of fresh transfusions are relatively anemic after donation and before reinfusion, recipients of impaired/repaired transfusions should also be mildly anemic for the study. Thus, they will donate another whole blood unit prior to beginning the study course, they will be transfused with their stored unit during the study, and then the autologous unit collected at the beginning of the day will be reinfused at the end of the day after the study is complete. | Biological | Fresh blood, then aged blood |
| Aged bloodIn a separate aim, the FMD assay will be used to investigate NO-mediated vasodilation in patients with CVD who are receiving transfusions. Over 60% of blood orders for cardiology patients at Emory are for 2 units or more. Therefore, when a 2-unit order is placed on a consented patient, they will be issued both fresh (< 7 days) and impaired (> 28 days) compatible units from inventory. Prior to starting transfusions, the patient will be randomized to either receive the fresh or the older unit first. All RBC units will be ACD/AS1. Units will also be leukoreduced and/or irradiated, if either of those modifications were found to impair NO bioavailability in prior studies. If washing or rejuvenation were found to be successful in significantly "repairing" NO bioavailability in previous aims, some patients may also receive impaired and repaired (> 28 days; washed or rejuvenated) RBC transfusions. | Biological | Fresh blood, then aged blood |
Primary outcome
The Effects of Storage-related RBC Changes on Acetylcholine-stimulated (NO-mediated) Forearm Blood Flow.
Time frame: 5 years
The primary outcome measures are changes in forearm blood flow (FBF) in recipients of fresh or stored RBC transfusions in response to acetylcholine. Secondary measures include changes in FBF with acetylcholine with or without L-NMMA, and changes in FBF with forearm exercise. In addition, flow mediated dilation (FMD) measurements will also be used to assess changes in brachial artery diameter before and after fresh vs aged RBC transfusions.
Results and safety
Loading the posted results from ClinicalTrials.gov…
Research links
- Official record on ClinicalTrials.govLast updated by the sponsor 6 Mar 2015.
- Posted resultsParticipant flow, baseline, all outcome measures and adverse events.
- Derived from this study: PubMed 26559401Hayek SS, Neuman R, Ashraf K, Sher S, Newman JL, Karatela S, Roback JD, Quyyumi AA. Effect of storage-aged red blood cell transfusions on endothelial function in healthy subjects. Transfusion. 2015 Nov;55(11):2768-70. doi: 10.1111/trf.13276. No abstract available.
- Derived from this study: PubMed 25393772Neuman R, Hayek S, Rahman A, Poole JC, Menon V, Sher S, Newman JL, Karatela S, Polhemus D, Lefer DJ, De Staercke C, Hooper C, Quyyumi AA, Roback JD. Effects of storage-aged red blood cell transfusions on endothelial function in hospitalized patients. Transfusion. 2015 Apr;55(4):782-90. doi: 10.1111/trf.12919. Epub 2014 Nov 13.
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Referral and contact
AzTrials does not enrol participants or take referrals. Contact the study team or a site listed below; they decide who can take part. This study is not recruiting at the moment.
Arshed A Quyyumi, MD principal investigator
Emory University
John Roback, MD, PhD principal investigator
Emory University
1 site in 1 country: see every site and its status.
Questions about this trial
What is this clinical trial studying?
A Phase 2 study testing Fresh blood and Aged blood in people with Healthy Volunteers, run by Emory University at 1 site in United States.
The full registered description is in the About this study section and the official record.
Who may be eligible to take part?
The sponsor lists 11 inclusion and 15 exclusion criteria. Eligibility is decided by the study team after screening, so read the full criteria and contact a listed site.
Is this clinical trial currently recruiting?
The record says: finished, as of the sponsor's last update on 6 Mar 2015. Status can change between updates, so confirm with the study contact before making plans.
Where is the study taking place?
The record lists 1 site in United States. Whether a site is taking part right now should be confirmed with that site. See every site.
What are the possible benefits and risks?
They depend on the study and the treatment, and no study can promise a benefit. The study team explains the known risks during informed consent, before anyone joins; the record itself does not list them.
What does this phase mean?
Phase 2 studies give the treatment to a larger group to see whether it has the intended effect and to keep checking safety.
Not every study follows the same path, and some studies (observational studies, device studies) have no phase.
Are results available for this study?
Yes. Results are posted in the registry (first posted 6 Mar 2015). A summary is in the For doctors view, and the full results are on ClinicalTrials.gov.
How can a doctor refer a patient or contact the research team?
The record lists no contact. The official record names the sponsor, who can be asked directly. AzTrials does not enrol participants or take referrals.
What does the primary outcome measure?
The Effects of Storage-related RBC Changes on Acetylcholine-stimulated (NO-mediated) Forearm Blood Flow. (time frame: 5 years). It is what the study was designed to measure, not a finding.
Where can I read the original study information?
On the ClinicalTrials.gov record for NCT00838331, which also lists 2 linked publications.
Does a listing mean the treatment is approved or proven to work?
No. A listing means the study is registered. It does not show that the treatment is safe, works, or is approved by a regulator.
How often is this information updated?
AzTrials copies changed records from ClinicalTrials.gov every night and reloads the whole registry every week. The sponsor last updated this record on 6 Mar 2015.