Feasibility of the use of a handheld XRF analyzer to measure skin iron to monitor iron levels in critical organs.

There exists a need for accurate, non-invasive point-of-care tests to detect body iron burden. This study investigated the use of x-ray fluorescence (XRF) measurements of skin iron as a marker for organ iron content in rats. This study also evaluated a novel application of a commercial XRF device, commonly used in mining and construction, as a rapid, portable, and non-invasive measurement tool. Rats (n = 32) were loaded with iron dextran and the iron signal of each animal's skin, liver, and kidney was measured using a conventional XRF system. A quadratic correlation was observed between liver and skin iron signal (R2 = 0.92) and a linear correlation was observed between kidney and skin iron signal (R2 = 0.65). As such, it is concluded that skin iron content can act as a marker for both liver and kidney iron content. The same skin samples were measured using the portable XRF device and compared to the liver and kidney samples measured in the conventional XRF system. Again, a quadratic correlation was observed between liver and skin iron signal (R2 = 0.91) and a linear correlation was observed between kidney and skin iron signal (R2 = 0.83). Thus, the portable XRF device can provide rapid non-invasive, skin XRF measurements. Dosimetry was performed using the portable XRF device to assess the radiological hazard associated with its use. The average skin equivalent dose from this device is 30 ± 10 mSv/min, when the device is collimated and operated at 40 kV. In conclusion, skin iron XRF measurements can act as a surrogate marker for liver iron content, and can be measured using a commercial XRF device for a portable, fast, and non-invasive measurement.

Group O RBCs: where is universal donor blood being used.

BACKGROUND: There have been recurrent shortages of group O blood due to insufficient inventory and use of group O blood in ABO non-identical recipients. We performed a 12-year retrospective study to determine utilization of group O Rh-positive and Rh-negative red blood cells (RBCs) by recipient ABO group. Reasons for transfusing group O blood to ABO non-identical recipients were also assessed. METHODS: Utilization data from all group O Rh-positive and Rh-negative RBCs transfused at three academic hospitals between April 2002 and March 2014 were included. Data were extracted from Transfusion Registry for Utilization Surveillance and Tracking, a comprehensive database with inventory information on all blood products received at the hospitals. Extracted data included product type, ABO and Rh, final disposition (transfused, wasted, outdated), and demographic and clinical data on all patients admitted to hospital. Descriptive statistics were performed using sas 9.3. RESULTS: There were 314 968 RBC transfusions: 151 645 (48·1%) were group O, of which 138 136 (91·1%) RBC units were transfused to group O individuals. ABO non-identical recipients received 13 509 group O RBCs (8·9%). The percentage of group O RBCs transfused to ABO non-identical recipients by fiscal year varied from 7·8% to 11·1% with a steady increase from 2011 to 2013. Reasons for this included: trauma, outdating, outpatient usage and shortages. CONCLUSION: The practice of transfusing O RBCs to non-O individuals has been increasing. Specific hospital and blood supplier policies could be targeted to change practice, leading to a more sustainable group O red blood cell supply.