A study on the use of PolyHeme as a blood replacement published in the January issue of the Journal of the American College of Surgeons was the first in the U.S. to assess survival of patients resuscitated with a hemoglobin-based oxygen carrier starting at the scene of injury.
In “Human Polymerized Hemoglobin for the Treatment of Hemorrhagic Shock when blood is unavailable: The multicenter trial,” the authors concluded that, “Although there were more adverse events in the PolyHeme group, the benefit-to-risk ration of PolyHeme is favorable when blood is needed but not available.”
Injured patients with systolic blood pressure of 90mmHg or less were randomized to receive either PolyHeme or crystalloids. Those receiving PolyHeme received up to 6 U of PolyHeme during the first 12 hours before getting blood. The control group received blood at the trauma centers. There were 714 patients in the study at 29 urban level I trauma centers. Blunt trauma comprised 48% of the patient the median transport time was 26 minutes.
In their report on the results of the study, the authors described no significant difference in 30-day mortality with PolyHeme and the control group. They described lower allogenic blood use with PolyHeme than with the control group. The authors anticipated adverse effects to be frequent with PolyHeme they were at 93% versus the control group’s 88% — as well as serious adverse events — at 40% for PolyHeme and 35% for the controls.
Previous studies caused concern over increased risk of myocardial infarctions with PolyHeme use. “Although myocardial infarction was reported by the investigators more frequently in the PolyHeme group (3% versus 1% control), a blinded committee of experts reviewed records of all enrolled patients and found no discernable difference between the groups,” the authors reported.
They concluded that, “Patients resuscitated with PolyHeme, without stored blood for up to 6U in 12 hours post injury, had outcomes favorable with those for the standard of care. Although there were more adverse events in the PolyHeme group, the benefit-to-risk ration of PolyHeme is favorable when blood is needed but not available.”
They noted a need for blood substitutes in situations where blood isn’t available to ensure patients have their best chance at definitive care and ultimately survival. They also noted that, in disaster and battlefield situations, “blood incompatibilities and shortages, and religious objections, represent additional situations in which PolyHeme can address this critical unmet need.”
The work of giving us a synthetic option to blood has continued to progress. Whether this study is the beginning of making it available to us in the field remains to be seen. But it’s encouraging that the work continues and that the risk/benefit is being closely scrutinized to ensure a safe option when blood isn’t an option.
Click hereto get Keith Wesley’s review on the latest PolyHeme study.