Association of red blood cells and plasma transfusion versus red blood cell transfusion only with survival for treatment of major traumatic hemorrhage in prehospital setting in England: a multicenter study

Background In-hospital acute resuscitation in trauma has evolved toward early and balanced transfusion resuscitation with red blood cells (RBC) and plasma being transfused in equal ratios. Being able to deliver this ratio in prehospital environments is a challenge. A combined component, like leukocyte-depleted red cell and plasma (RCP), could facilitate early prehospital resuscitation with RBC and plasma, while at the same time improving logistics for the team. However, there is limited evidence on the clinical benefits of RCP. Objective To compare prehospital transfusion of combined RCP versus RBC alone or RBC and plasma separately (RBC + P) on mortality in trauma bleeding patients. Methods Data were collected prospectively on patients who received prehospital transfusion (RBC + thawed plasma/Lyoplas or RCP) for traumatic hemorrhage from six prehospital services in England (2018–2020). Retrospective data on patients who transfused RBC from 2015 to 2018 were included for comparison. The association between transfusion arms and 24-h and 30-day mortality, adjusting for age, injury mechanism, age, prehospital heart rate and blood pressure, was evaluated using generalized estimating equations. Results Out of 970 recruited patients, 909 fulfilled the study criteria (RBC + P = 391, RCP = 295, RBC = 223). RBC + P patients were older (mean age 42 vs 35 years for RCP and RBC), and 80% had a blunt injury (RCP = 52%, RBC = 56%). RCP and RBC + P were associated with lower odds of death at 24-h, compared to RBC alone (adjusted odds ratio [aOR] 0.69 [95%CI: 0.52; 0.92] and 0.60 [95%CI: 0.32; 1.13], respectively). The lower odds of death for RBC + P and RCP vs RBC were driven by penetrating injury (aOR 0.22 [95%CI: 0.10; 0.53] and 0.39 [95%CI: 0.20; 0.76], respectively). There was no association between RCP or RBC + P with 30-day survival vs RBC. Conclusion Prehospital plasma transfusion for penetrating injury was associated with lower odds of death at 24-h compared to RBC alone. Large trials are needed to confirm these findings

Phylogenetic ctDNA analysis depicts early-stage lung cancer evolution.

The early detection of relapse following primary surgery for non-small-cell lung cancer and the characterization of emerging subclones, which seed metastatic sites, might offer new therapeutic approaches for limiting tumour recurrence. The ability to track the evolutionary dynamics of early-stage lung cancer non-invasively in circulating tumour DNA (ctDNA) has not yet been demonstrated. Here we use a tumour-specific phylogenetic approach to profile the ctDNA of the first 100 TRACERx (Tracking Non-Small-Cell Lung Cancer Evolution Through Therapy (Rx)) study participants, including one patient who was also recruited to the PEACE (Posthumous Evaluation of Advanced Cancer Environment) post-mortem study. We identify independent predictors of ctDNA release and analyse the tumour-volume detection limit. Through blinded profiling of postoperative plasma, we observe evidence of adjuvant chemotherapy resistance and identify patients who are very likely to experience recurrence of their lung cancer. Finally, we show that phylogenetic ctDNA profiling tracks the subclonal nature of lung cancer relapse and metastasis, providing a new approach for ctDNA-driven therapeutic studies

High-sensitivity online detection for microfluidics via cavity ringdown spectroscopy

We report the coupling of cavity ringdown spectroscopy (CRDS) with a microfluidic chip fabricated using a rapid prototyping method, in order to demonstrate high-sensitivity, non-contact online detection in microfluidics. Conventional UV-vis absorption techniques are largely ineffective for microfluidic detection due to the small sample volumes and short path lengths. The multipass absorption achieved in cavity ringdown spectroscopy increases the effective absorption pathlength by several orders of magnitude, and hence enhances the detection sensitivity. A cavity ringdown spectrometer, operating at a single wavelength of 532 nm for the purposes of the proof-of-concept measurements presented here, has been developed for online detection on a polymer/glass microchip fabricated by frontal photopolymerisation. High sensitivity absorption measurements on liquid samples with volumes of tens to hundreds of nanolitres and absorption pathlengths ranging from tens to hundreds of microns are demonstrated. A series of proof-of-concept experiments show that the technique has the ability to monitor both static and time-varying analyte concentrations. Firstly, the detection limit of the system is estimated from a three-standard-deviation error analysis of absorption measurements made on dilute aqueous solutions of potassium permanganate (natural absorption coefficient (4805 ± 10) M-1 cm-1 at 532 nm). The detection limit was found to be ∼210 nM for a 466 μm pathlength, corresponding to an absorption of 1.0 × 10-3 cm-1. Online pH measurements on a 20 nL sample are performed by monitoring the absorption of phenolphthalein indicator present at millimolar concentrations. Finally, CRDS has been applied, for the first time, to monitoring chemical reaction kinetics on a microfluidic chip, tracking the oscillation period of the well-known Belousov-Zhabotinsky reaction. © 2012 The Royal Society of Chemistry