Prehospital use of plasma: the blood bankers' perspective.

At the 2013 Traumatic Hemostasis and Oxygenation Research Network's Remote Damage Control Resuscitation symposium, a panel of senior blood bankers with both civilian and military background was invited to discuss their willingness and ability to supply prehospital plasma for resuscitation of massively bleeding casualties and to comment on the optimal preparations for such situations. Available evidence indicates that prehospital use of plasma may improve remote damage control resuscitation, although level I evidence is lacking. This practice is well established in several military services and is also being introduced in civilian settings. There are few, if any, clinical contraindications to the prehospital use of plasma, except for blood group incompatibility and the danger of transfusion-induced acute lung injury, which can be circumvented in various ways. However, the choice of plasma source, plasma preparation, and logistics including stock management require consideration. Staff training should include hemovigilance and traceability as well as recognition and management of eventual adverse effects. Prehospital use of plasma should occur within the framework of clinical algorithms and prospective clinical studies. Clinicians have an ethical responsibility to both patients and donors; therefore, the introduction of new clinical capabilities of transfusion must be safe, efficacious, and sustainable. The panel agreed that although these problems need further attention and scientific studies, now is the time for both military and civilian transfusion systems to prepare for prehospital use of plasma in massively bleeding casualties.

Trends in transfusion of trauma victims--evaluation of changes in clinical practice.

BACKGROUND: The present study was performed to compare blood product consumption and clinical results in consecutive, unselected trauma patients during the first 6 months of year 2002, 2004 and 2007. METHODS: Clinical data, blood product consumption, lowest haemoglobin values on day 1-10 after admission, and 30-day mortality were extracted from in-hospital trauma registry and the blood bank data base. The subpopulation of massively transfused patients was identified and analysed separately. RESULTS: The total number of admitted trauma patients increased by 48% from 2002 to 2007, but the clinical data remained essentially unchanged. The mean number of erythrocyte units given day 1-10 decreased insignificantly from 9.4 in 2002 to 6.8 in 2007. New Injury Severity Score (NISS) increased in transfused and massively transfused patients, but not significantly. The number of patients transfused with plasma increased and the mean ratio of erythrocyte to plasma units transfused decreased by about 50%. The mean haemoglobin value in transfused patients on day 2 after admittance was significantly lower in 2007 than in 2002, while that on day 10 was significantly higher in 2007 than in 2002 and 2004. There was no change of 30-day survival from 2002 to 2007. CONCLUSIONS: Significant changes of transfusion practice occurred during the past decade, probably as a result of increased focus on haemostasis and more precise criteria for transfusion. Despite a lower consumption of erythrocytes in 2007 than in 2002 and 2004, the mean haemoglobin level of transfused patients was higher on day 10 in 2007. The low number of transfused patients in this material makes evaluation of effect on survival difficult. Larger studies with strict control of all influencing factors are needed.

The acidosis-induced right shift of the HbO2 dissociation curve is maintained during erythrocyte storage.

BACKGROUND AND OBJECTIVES: In fresh blood, tissue hypoxia increases microcirculatory acidosis, which enhances erythrocyte O(2) unloading and increases the amount of available O(2). Storage of erythrocytes increases the HbO(2) affinity and reduces O(2) unloading. We examined the development of the affinity change during a period of 5 weeks of storage by present blood bank standards, and investigated to what extent acidosis offsets the affinity change. MATERIALS AND METHODS: Blood from volunteer donors was processed and stored as erythrocyte concentrates (EC). At 2-5 day intervals, EC were drawn from the bags and suspended in plasma and crystalloids to an Hb ≈ 10 g/dL. The suspensions were adjusted to give a pH of 7.40, 7.10, 6.80 or 6.30 and equilibrated with different gas mixtures to SO(2) 0, 25, 50, 75 and 100%. Measurements of the PO(2)/SO(2) pairs at each pH were used to calculate the position of the HbO(2) curve and its P(50) value. RESULTS: A significant leftward shift in the HbO(2) curve was established after 1 week of storage; after 2.5 weeks only minor further changes were observed. Acidification right-shifted the HbO(2) curve, after 2.5 weeks of storage the curve at pH 7.10 was similar to that for fresh blood at pH 7.40. Calculations of extractable O(2) showed that the left-shifted HbO(2) curve of stored EC could be advantageous at a low arterial PO(2). CONCLUSIONS: The rightward shift of the HbO(2) curve due to acidosis is well maintained in stored erythrocytes, a moderate pH decrease offsets the storage-induced increased HbO(2) affinity.