Identification of modifiable risk factors for acute kidney injury after cardiac surgery.

OBJECTIVES: Acute kidney injury (AKI) is a common problem after cardiac surgery and is associated with an increase in morbidity, mortality and duration of hospital stay. With this study we aimed to identify potential risk factors for cardiac surgery associated AKI (CS-AKI) in a single-centre population with a special focus on modifiable risk factors. METHODS: Retrospective single-centre cohort study of 565 consecutive patients who underwent isolated coronary artery bypass grafting (CABG) with the use of cardiopulmonary bypass. AKI was defined by the AKIN classification. Known risk scores were applied when possible. RESULTS: Of the population, 14.7% were diagnosed with AKI. When considering baseline characteristics we found a significant difference in age, preoperative estimated glomerular filtration rate (eGFR) and chronic kidney disease (CKD) stage and urgency of surgery between the CS-AKI group and the control population. Regarding the intraoperative characteristics, patients with CS-AKI had a significantly lower haematocrit and were more likely to receive a transfusion of packed cells. Postoperative administration of furosemide and packed cell transfusions were also associated with AKI. We found no differences in other characteristics (history of diabetes mellitus, history of congestive heart failure, sex, body mass index (BMI), history of cardiac surgery, low cardiac output and need for intra-aortic balloon pump (IABP), duration of cardiopulmonary bypass (CPB) and cross clamping). CONCLUSION: In our series we could identify intraoperative administration of packed cells and postoperative administration of furosemide or packed cells as potentially modifiable risk factors in the development of AKI.

JAK2 V617F mutation and PRV-1 overexpression: relevance in the diagnosis of polycythaemia vera and essential thrombocythaemia.

In the diagnosis of polycythaemia vera and essential thrombocythaemia, two molecular markers were described in the last decade: the overexpression of the PRV-1 gene and the V617F mutation in the JAK2 gene. In this study we assess their usefulness by comparing our test results with the available clinical data. We show that in the diagnosis of polycythaemia vera the JAK2 mutation screening is crucial, while testing for the PRV-1 overexpression is redundant. On the contrary, in the diagnosis of essential thrombocythaemia (ET), both JAK2 and PRV-1 show their usefulness.

Future perspectives in bioreactor development.

The paper discusses conversion capacities of both anaerobic and aerobic wastewater treatment systems in relation to growth kinetics, hydrodynamics and biomass concentration. In the current modern anaerobic high-rate reactors the conversion potentials are optimally exploited. This is not yet true for aerobic systems since operation of aerobic systems under conditions of low biomass growth reduces the maximum applicable loading rates significantly. Both the concept of granulation and the introduction of fluidised bed systems have increased conversion capacities for both anaerobic and aerobic systems significantly. One of the latest development concerns the SBR with granular biomass. The grazing concept, in which ciliates convert aerobically grown dispersed cells, offers a possibility for significant improvement of aerobic systems. In the fields of psychrophilic and thermophilic anaerobic treatment, specific reactor development may contribute to further enhance volumetric conversion capacities. Due to reduced water usage, both COD and salt concentrations tend to increase for industrial effluents. As a consequence, there is a need for the development of anaerobic reactors retaining flocculant biomass. The membrane bioreactors offer a solution for certain niches in wastewater treatment. However the oxygen transfer economy is poor. There is a need for fundamental knowledge development to obtain a realistic image of this technology.