Randomized trial of red cell washing for the prevention of transfusion-associated organ injury in cardiac surgery.

BACKGROUND: Experimental studies suggest that mechanical cell washing to remove pro-inflammatory components that accumulate in the supernatant of stored donor red blood cells (RBCs) might reduce inflammation and organ injury in transfused patients. METHODS: Cardiac surgery patients at increased risk of large-volume RBC transfusion were eligible. Participants were randomized to receive either mechanically washed allogenic RBCs or standard care RBCs. The primary outcome was serum interleukin-8 measured at baseline and at four postsurgery time points. A mechanism substudy evaluated the effects of washing on stored RBCs in vitro and on markers of platelet, leucocyte, and endothelial activation in trial subjects. RESULTS: Sixty adult cardiac surgery patients at three UK cardiac centres were enrolled between September 2013 and March 2015. Subjects received a median of 3.5 (interquartile range 2-5.5) RBC units, stored for a mean of 21 ( sd 5.2) days, within 48 h of surgery. Mechanical washing reduced concentrations of RBC-derived microvesicles but increased cell-free haemoglobin concentrations in RBC supernatant relative to standard care RBC supernatant. There was no difference between groups with respect to perioperative serum interleukin-8 values [adjusted mean difference 0.239 (95% confidence intervals -0.231, 0.709), P =0.318] or concentrations of plasma RBC microvesicles, platelet and leucocyte activation, plasma cell-free haemoglobin, endothelial activation, or biomarkers of heart, lung, or kidney injury. CONCLUSIONS: These results do not support a hypothesis that allogenic red blood cell washing has clinical benefits in cardiac surgery. CLINICAL TRIAL REGISTRATION: ISRCTN 27076315.

Trial protocol for a randomised controlled trial of red cell washing for the attenuation of transfusion-associated organ injury in cardiac surgery: the REDWASH trial.

INTRODUCTION: It has been suggested that removal of proinflammatory substances that accumulate in stored donor red cells by mechanical cell washing may attenuate inflammation and organ injury in transfused cardiac surgery patients. This trial will test the hypotheses that the severity of the postoperative inflammatory response will be less and postoperative recovery faster if patients undergoing cardiac surgery receive washed red cells compared with standard care (unwashed red cells). METHODS AND ANALYSIS: Adult (≥16 years) cardiac surgery patients identified at being at increased risk for receiving large volume red cell transfusions at 1 of 3 UK cardiac centres will be randomly allocated in a 1:1 ratio to either red cell washing or standard care. The primary outcome is serum interleukin-8 measured at 5 postsurgery time points up to 96 h. Secondary outcomes will include measures of inflammation, organ injury and volumes of blood transfused and cost-effectiveness. Allocation concealment, internet-based randomisation stratified by operation type and recruiting centre, and blinding of outcome assessors will reduce the risk of bias. The trial will test the superiority of red cell washing versus standard care. A sample size of 170 patients was chosen in order to detect a small-to-moderate target difference, with 80% power and 5% significance (2-tailed). ETHICS AND DISSEMINATION: The trial protocol was approved by a UK ethics committee (reference 12/EM/0475). The trial findings will be disseminated in scientific journals and meetings. TRIAL REGISTRATION NUMBER: ISRCTN 27076315.

Airways allergic inflammation and L. reuterii treatment in asthmatic children.

Recently, it has been hypothesized that the oral administration of specific live probiotic strains may have therapeutic potential in the treatment of allergic inflammation. The aim of this study was to evaluate the effect of the oral L. reuteri DSM 17938 administration (1X108CFU), in airways allergic inflammation in mild persistent asthmatic children. In this DBPC randomized study we selected 50 children (6-14 years old), affected by mild persistent asthma (GINA step 2) and allergic to HDM. At the run-in period (T-2), the children were submitted to medical examination, prick tests for the main respiratory allergens, spirometry and children asthma control test (C-ACT). We selected only the children with well controlled asthma (C-ACT >19 and FEV1> 80%). After two weeks (T0) the children were allocated into two groups, the FeNO was measured and the breath condensate was collected. Group A children were treated with the placebo (5 drops per day) and Group B children with L. reuteri (108CFU =5 drops per day) for 60 days. After the treatment period (T1), all patients were evaluated by medical examination, C-ACT, spirometry, FeNO measurement and exaled breath condensate analysis. The FeNO values showed a significant reduction (p=0,045) in L. reuteri group but not in the placebo group at the end of the treatment (T1). Furthermore, the cytokines exam showed an increase in IL-10 levels (p less than 0.05) and a significant reduction in IL-2 levels (p less than 0.05) only in L. reuteri group at T1. No significant differences in FEV1 values and C-ACT score were found in both groups. In conclusion, these data showed that L. reuteri (108 CFU) was effective in reducing bronchial inflammation in asthmatic children. No significant effect was found on FEV1 values and C-ACT score, probably because we selected children with well controlled asthma.

Gradient-index eyepiece design.

A study of gradient-index eyepieces was conducted. The general performance of homogeneous eyepieces having two and three elements was examined. Axial gradients were introduced into the eyepieces in an attempt to increase the half-fields of view to 25 degrees and extend the eye reliefs to 12 mm. The homogeneous eyepieces examined were of the Huygenian, Ramsden, and Kellner configurations. These eyepieces were scaled to the specifications of f/13, 21.4-mm focal length, and magnifying power of 10X. These classic systems were optimized to produce two- and three-element homogeneous eyepieces to determine how homogeneous systems could perform with the extended eye relief and larger field of view. Axial gradient eyepieces having two and three elements were designed to the same specifications. The balance of third-order aberrations, color, and distortion was maintained or improved compared to the homogeneous systems.. The additional degrees of freedom associated with the gradient made it possible to extend the eye relief and increase the field of view of these eyepieces.

Imaging capabilities of a long gradient-index rod.

The possibilities of transmitting spatial information through a long gradient-index rod are presented. Spatial resolution vs rod diameter are optimized for both visible and IR transmitting systems.