Photo by Cristina Granados
Bags of plasma
Receiving a plasma transfusion during emergency air transport can improve survival for trauma patients, according to a study published in NEJM.
Trauma patients with severe bleeding had a significant decrease in 30-day mortality when they received a plasma transfusion while being airlifted to a hospital.
Transfusion-related reactions and allergic reactions were more common among plasma recipients than patients who only received standard care.
However, this difference was not significant, and most of these reactions were considered minor.
“These results have the power to significantly alter trauma resuscitation, and their importance to the trauma community cannot be overstated,” said study author Jason Sperry, MD, of the University of Pittsburgh School of Medicine in Pennsylvania.
“This is the first trial in a quarter century to have the potential to alter prehospital care so considerably.”
Patients and intervention
This trial, known as PAMPer (Prehospital Air Medical Plasma), was a phase 3, randomized study enrolling 501 trauma patients at risk of hemorrhagic shock.
Most patients were male (72.7%), and most had suffered blunt trauma (82.4%). About half of patients (51.1%) had prehospital intubation, and more than a third (34.7%) received a prehospital transfusion of red blood cells.
Air medical bases participating in this study were randomized to administer plasma or standard care to eligible patients for 1-month intervals. When the air transport teams were in their plasma interval, they’d begin administering 2 units of thawed plasma to a patient as soon as trial eligibility was confirmed.
If the 2 units were completed during the flight, the team would revert to standard care. If the transfusions weren’t completed, the plasma would continue to be administered when the patient arrived at the trauma center.
The teams administered the assigned treatment 99% of the time (496/501).
In the plasma group, there were 205 patients (89.1%) who received 2 units of plasma, 21 (9.1%) who received 1 unit, and 4 patients (1.7%) who did not receive plasma due to logistical challenges.
In 84.4% of the patients, the plasma infusion was completed during air transport. The remaining patients completed their plasma transfusions at the trauma center.
There was 1 patient (0.4%) in the standard-care group who received plasma before transport began.
Primary outcome
The study’s primary outcome was 30-day mortality. Ninety-six percent of patients (n=481) had data for this outcome—220 patients in the plasma group and 261 in the standard-care group.
Thirty-day mortality was significantly lower in the plasma group than the standard-care group—23.2% and 33.0%, respectively (P=0.03).
In an adjusted analysis, the administration of prehospital plasma was associated with a 39% lower risk for 30-day mortality than standard care (adjusted odds ratio, 0.61; P=0.02).
Secondary outcomes
Initially, there were significant differences between the plasma (n=230) and standard-care groups (n=271) when it came to:
- Mortality at 24 hours—13.9% and 22.1%, respectively (P=0.02)
- In-hospital mortality—22.2% and 32.5%, respectively (P=0.01)
- Median volume of blood components transfused in the first 24 hours—3 and 4 units, respectively (P=0.02)
- Median volume of red cells transfused in the first 24 hours—3 and 4 units, respectively (P=0.03).
- Median prothrombin-time ratio at first blood sampling—1.2 and 1.3, respectively (P<0.001).
When the researchers adjusted P values for multiple comparisons, the between-group difference in prothrombin-time ratio remained significant (P<0.001).
However, the differences in 24-hour mortality (P=0.55), in-hospital mortality (P=0.33), blood components transfused (P=0.41), and red cells transfused (P=0.69) did not retain significance.
Likewise, there were no significant between-group differences (in adjusted or unadjusted analyses) when it came to multi-organ failure, acute lung injury/acute respiratory distress syndrome, nosocomial infections, or allergic/transfusion-related reactions.
There were 10 adverse events (AEs) considered related to the trial regimen. In the standard-care group, the 4 AEs were sepsis (a serious AE), adult respiratory distress syndrome (a serious AE), fever, and pain.
In the plasma group, the 6 AEs were 2 allergic reactions, 1 case of anaphylaxis, 1 case of hypotension, 1 case of urticaria, and 1 transfusion-related reaction (a serious AE).