Transforming transfusions: U. researcher explains new international guidelines on blood supply

Earlier this month, an international team of 27 medical experts developed and published new guidelines for red blood cell transfusions and blood supply preservation in clinical settings, according to a press release.

The guidelines recommend a more restrictive procedure to assess when patients receive blood transfusions. The team conducted research with numerous randomized clinical trials, including 45 studies of adults and seven studies of pediatric populations, to reach this conclusion, according to the release.

Jeffrey Carson, the provost at Rutgers Biomedical Health Sciences—New Brunswick and a distinguished professor at Robert Wood Johnson Medical School, said that the guidelines focus on two primary topics: the effect of the age of blood on transfusions and the hemoglobin thresholds used to initiate transfusions.

He said that most blood transfusions are performed in a hospital setting and are common practice for various medical situations, including surgeries with blood loss, internal or spontaneous bleeding and underlying blood complications.

The previous version of the guidelines established that medical professionals could use appropriately stored blood for transfusions, as the expert panel determined that there was no benefit from using a fresher blood supply, Carson said.

He said the recent guidelines delve deeper into the hemoglobin-based thresholds that dictate when patients receive a blood transfusion — 9 to 10 grams for liberal transfusions and 7 to 8 grams for restrictive transfusions.

The new research trials and greater availability of data reaffirm the recommendation of previously published guidelines in favor of restrictive blood transfusions, Carson said.

This not only provides the same level of patient safety but also circumvents medical side effects and expenses from unnecessary blood transfusions, he said.

Carson said the recent guidelines are more refined for medical practitioners to follow and include blood transfusion recommendations specific to children.

Regarding blood shortages, such as the national shortage during the coronavirus disease (COVID-19), Carson said different transfusion strategies selected by doctors impact the blood supply differently.

For example, a restrictive transfusion strategy utilizes less blood, thus depleting the blood supply slower compared to a more liberal transfusion approach, he said.

"During (the pandemic), the number of volunteers who were donating fell … and the blood supply became an issue, and we had to be even more careful about how we chose to transfuse patients," Carson said. "(Now), in central New Jersey, there have not been shortages of late, so you can get the blood you need."

He said the new guidelines still account for some groups of patients with heart and neurological problems for whom the restrictive blood transfusion threshold may not be appropriate to follow.

"One of the key principles … is red blood cells," Carson said. "One of their big functions is to capture oxygen from the lungs and then deliver it to the tissues, to the organs ... Those organs are potentially very sensitive to lower blood counts where you're not able to deliver enough oxygen. The research around those particular areas have not been completed."

He said the guidelines highlight these concerns for patients with severe heart or brain conditions and recommend that doctors not necessarily use the thresholds suggested for most other demographic groups.

On adopting these new guidelines, Carson said that the restrictive threshold has been thoroughly accepted in the medical field and integrated as the standard of care in most hospitals, but pointed out that the warnings for certain patient groups are not as widely acknowledged.

"There's nothing in medicine that's universal," he said. "Many physicians and health care providers have said, 'Well, we're just going to use a lower threshold in everyone.' … I don't think that's necessarily the right thing to do. I don't think we know just yet."

Carson said that he advises students to learn how to better communicate with their medical providers on the subject of blood transfusions and other aspects of health care.

"Rutgers students (can't) be their doctors," he said. "They have to find doctors that are knowledgeable about these issues and ask questions. I think a wise consumer of medical care is one that is questioning and discussing options with their providers and understanding the rationale behind whatever treatment is offered to them."