Advances in transfusion science for shock-trauma: Optimising the clinical management of acute haemorrhage

Higher Crystalloid Volume During Initial Pediatric Trauma Resuscitation is Associated With Mortality

BACKGROUND

Historically, aggressive fluid resuscitation has been a cornerstone of management of hemorrhagic shock in pediatrics. Adult data suggest this strategy may be harmful. We sought to determine whether aggressive fluid resuscitation within the first hour of presentation to the emergency department in pediatric patients with trauma is associated with worse clinical outcomes.

MATERIALS AND METHODS

We performed a retrospective cohort study from 2012 to 2017 at a single pediatric level 1 trauma center. We defined three patient cohorts: ≤ 20 cc/kg (reference), 20-40 (20.01 to 39.99) cc/kg, and ≥40 cc/kg of intravenous fluid (IVF) given in the first in-hospital hour. Covariates included age, injury severity score, shock index (adjusted for age), and mechanism of injury and were adjusted for with multivariable regression. The primary outcome was in-hospital mortality.

RESULTS

A total of 1479 consecutive injured children were eligible for inclusion. One hundred ninety-four patients were excluded for missing IVF data, aged ≥16 y, having primary burns, or arriving pulseless. A total of 1285 patients met inclusion criteria (mean age 8.1 ± 5.5 y, male 64.5%). Higher rates of IVF administration were associated with mortality for both the 20-40 cc/kg (adjusted odds ratio (aOR) 2.96; 95% confidence interval (CI) 1.02-8.55; P = 0.045) and ≥40 cc/kg groups (aOR 6.26; 95% CI 1.79-21.83; P = 0.004). The ≥40 cc/kg group was associated with increased pediatric intensive care unit length of stay (aOR 2.20; 95% CI: 1.05-4.61; P = 0.036) and increased need for mechanical ventilation (aOR 3.79; 95% CI 1.62-8.87; P = 0.002).

CONCLUSIONS

Greater than one 20 cc/kg IVF bolus in the first emergency department hour was associated with mortality with a dose-response relationship, even after adjusting for injury severity and initial hemodynamics. These results encourage further investigation into initial resuscitation strategies for injured children.

Cumulative erythrocyte damage in blood storage and relevance to massive transfusions: selective insights into serial morphological and biochemical findings

Elucidating the precise mechanisms of cumulative red cell damages during storage and the potential harmful consequences after transfusion are achievable by exacting laboratory science and well-defined clinical studies in progress. Accordingly, for larger magnitude blood transfusions (i.e. 8-12 U in 24 hours), the quality of the stored blood and its characterisation are of special academic and clinical importance. Our main objectives in this review are to illuminate facets of the red cell storage lesion for prolonged storage (0-42 days) by concentrating on various hallmarks of the disorder: 1) identifying and characterising serial markers of the progressive lesion with respect to red cell dysmorphology, deformability, haemolytic fragility and dysfunction both in storage and the microcirculation; and 2) relevant biochemical findings of redox status correlated to oxidative stress of erythrocyte proteins. This is accomplished in part by reliance on advanced metabolomic and proteomic technologies using various sophisticated tools such as high pressure liquid chromatography in combination with mass spectrometry of proteins and small molecule metabolites. It is anticipated that these sophisticated methodologies and the experimental results therein shall lead to further advances in the quality improvement of red cell storage.

Unresolved clinical aspects and safety hazards of blood derived- EV/MV in stored blood components: From personal memory lanes to newer perspectives on the roles of EV/MV in various biological phenomena

Blood cells generate heterogeneous populations of vesicles that are delivered, as small-specialized packages of highly active cell fragments in blood circulation, having almost similar functional activities, as the mother cells. These so called extracellular vesicles are the essential part of an energy-dependent natural apoptotic process; hence their beneficial and harmful biological functions cannot be ignored. Evidence is accumulating, that cellular derived vesicles, originate from all viable cells including: megakaryocytes, platelets, red blood cells, white blood cells and endothelial cells, the highest in proportions from platelets. Shedding can also be triggered by pathological activation of inflammatory processes and activation of coagulation or complement pathways, or even by shear stress in the circulation. Structurally, so called MV/EV appear to be, sometimes inside-out and sometimes outside-in cell fragments having a bilayered phospholipid structure exposing coagulant-active phosphatidylserine, expressing various membrane receptors, and they serve as cell-to-cell shuttles for bioactive molecules such as lipids, growth factors, microRNAs, and mitochondria. Ex vivo processing of blood into its components, embodying centrifugation, processing by various apheresis procedures, leukoreduction, pathogen reduction, and finally storage in different media and different types of blood bags, also have major impacts on the generation and retention of MV content. These artificially generated small, but highly liable packages, together with the original pool of MVs collected from the donor, do exhibit differing biological activities, and are not inert elements and should be considered as a parameter of blood safety in haemovigilance programmes. Harmonization and consensus in sampling protocols, sample handling, processing, and assessment methods, in particular converting to full automation, are needed to achieve consensual interpretations. This review focuses on some of our past personal studies on the role of MV/EV focusing on characterization of platelet storage lesion and platelet therapy that shows the highest transfusion hazards [up to 25%], and loss of 25% platelet efficacy after various leukoreduction and validated platelet pathogen reduction treatments. The planned paths for the future of EV/MV involvement in immunological and viral/ non-viral transfusion hazards are also discussed. Whilst considerable advances made on the characterization of EV/MV, but disparity still exists between various surrogate markers, showing some subtle differences in the levels of MV/ EV & BRMs in platelet preparations, and the clinical outcome showing platelets derived by all current technologies are equivalents in vivo. One possible reason for such a disparity may be relatedto the fact that MVs, being the end products of apoptotic cells, have little specificity and clear rapidly from circulation [<6 h in thrombocytopoenia]. This makes their clinical usefulness rather short lived. The recent findings that pegylating smaller subsets of EV increases its circulatory life from <15 minutes to approximately about one hour is highly promising, in particular, for drug delivery on specific sides. Hence a promising clinical utility of EV/MV continues, as a journey without end, indeed. This manuscript is based mainly on the selected key readings listed below.