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Abstract: Freezing and thawing resistance is very important characteristic also in the case of lightweight concrete. The paper deals with the influence of periodic freeze–thaw cycles on lightweight concrete fracture parameters values. Sets of lightweight concrete specimens (prismatic shape) are cyclically frozen in range from +20 °C to −20 °C. The main aim of the experimental part is to determine and compare the mechanical/fracture parameter values of a composite both frozen and non-frozen. The non-frozen specimens are air/water-cured. A three-point bending test of beams with a central edge notch is used in order to determine the fracture parameters values. It particularly covers effective fracture toughness and fracture energy. The notch is cut after 200 freezing cycles before fracture tests. The other parameters values–compressive and splitting tensile strength on the specimen fragments–are determined. [Copyright &y& Elsevier]

Abstract: This paper deals with the influence of periodic freezing on lightweight concrete characteristics. Sets of lightweight concrete prismatic specimens are cyclically frozen in range from 20 °C to −20 °C and non-destructively tested after every 25 cycles. Freeze-thaw resistance is determined from measurement of the frost-attacked and non-frost-attacked (referential) specimens. The referential specimens are air/water-cured. Non-destructive methods, especially ultrasonic impulse method and resonance method are used for determination of specimen’s degradation. Experiments are finished with destructive test in order to determine the static modulus of elasticity. [Copyright &y& Elsevier]

Broad-range PCR has the potential to detect virtually any bacterial species via amplification and nucleotide sequencing of a DNA region common to all bacteria. We aimed to evaluate its usefulness and clinical relevance when applied to a wide variety of primary sterile materials. A prospective study including 1370 samples (75 heart valves, 151 joint tissue samples, 230 joint aspirates, 848 whole blood samples and 66 culture-negative cerebrospinal fluid samples) were studied by using a commercial PCR system for detecting 16S rDNA (Molzym). The PCR results were compared with culture and were considered to provide added diagnostic value only if the PCR approach revealed new pathogens that were missed by culture. The added value of PCR was evident in 173 of 555 PCR-positive samples (0.126; 0.109–0.144 (proportion from all tested samples; 95% confidence interval)), most frequently in examinations of heart valves (0.56; 0.448–0.672) and joint tissue samples (0.219; 0.153–0.284). In contrast, the lowest rate of PCR with added value was noted for blood samples, regardless of the patient cohort they had been drawn from (nononcologic patients from intensive care: 0.065; 0.043–0.087, haematooncologic children: 0.048; 0.027–0.070). Moreover, PCR missed up to 7.1% of blood culture findings (0.071; 0.048–0.095) regarded as clinically relevant, which was the second highest failure rate after joint tissue samples (0.099; 0.052–0.147). Broad-range PCR substantially increases detection rate of pathogens, especially from heart valves and joint samples. However, a concurrent risk of false-negative PCR results justifies the need for parallel culture. [ABSTRACT FROM AUTHOR]

Lung transplantation is often accompanied with significant bleeding and coagulopathy. Perioperative management usually consists of administering of fresh frozen plasma (FFP) and red blood cells. However, usage of blood transfusion products, especially FFP, may be associated with higher morbidity of patient. Point of care (POC) monitoring of coagulopathy by thrombelastometry (ROTEM), platelet function analyzer (PFA 200) and agregometer (Multiplate) and subsequent aimed therapy may lead to decreased consumption of FFP. The purpose of this study is to investigate if POC based monitoring and treatment of coagulopathy may decrease consumption of FFP, APACHE II (Acute Physiology and Chronic Health Evaluation) and SOFA (Sequential Organ Failure Assessment) scores. Patients undergoing bilateral lung transplantation were randomized into 2 groups. In the first group (non-POC group) management of bleeding and coagulopathy was based on anesthesiologist´s experience by administering FFP or other coagulation factors. In the second group (POC group) management of coagulopathy was based on results of POC methods such as ROTEM, PFA 200, Multiplate and 5% albumin solution was used to maintain normovolemia. Total number of analyzed patients is 46. In POC group no FFP unit was used at all. Admission APACHE II score as well as SOFA score 24 hours after admission was significantly decreased in POC group of patients (p<0.05). Results are shown on Figure. Perioperative usage of POC methods such as ROTEM, PFA 200 and Multiplate to diagnose and treat coagulopathy significantly reduces consumption of FFP and may decrease APACHE II and SOFA score in patients undergoing lung transplantation. The study is registered in clinical trial database with number: CTN03598907. [ABSTRACT FROM AUTHOR]

Purpose Primary Graft Dysfunction (PGD) is the most common complication during the first 72 hours after lung transplant. Amount of perioperative blood loss and blood product administration may be some of the causes. Intravascular volume during surgery and in ICU is usually maintained by the administration of crystalline and colloids solutions and by administration of fresh frozen plasma (FFP) due to coagulopathy. In the field of the allogenic ischemic organ FFP essentially becomes another allogenic material and can cause undesired immunomodulation and contribute to the development of PGD. Nowadays point of care (POC) management of coagulopathy and bleeding is available using methods such as thromboelastometry (ROTEM), platelet function analyzer (PFA 200) and agregometer (Multiplate) which contribute to the optimalization of blood products and coagulation factors administration. The purpose of this study is to find out if POC management of perioperative bleeding and coagulopathy can reduce postoperative PGD development and length of artificial ventilation. Methods 18 patients undergoing bilateral lung transplantation were randomized into 2 groups. In the first group (9 subj) the management of perioperative bleeding or coagulopathy and volume replacement strategy were based on clinical experience of the anesthesiologist - standard approach. In the second group (9 subj) the management of perioperative bleeding and coagulopathy was based on the results of POC methods. Albumin 5% solution was preferably used for volume replacement therapy. Results In the POC management group PGD development, length of artificial ventilation and langht of stay was significantly reduced. Conclusion POC management of perioperative bleeding or coagulopathy and volume replacement strategy with Albumin 5% significantly reduce PGD development and decrease length of stay and artificial ventilation. [ABSTRACT FROM AUTHOR]

Purpose Lung transplantation is very often accompanied with significant bleeding and coagulopathy. Standard perioperative management consists of administering fresh frozen plasma (FFP) and red blood cells. These transfusion products are generally administered according to anesthesiologist's decision based on his personal experience. However, point of care (POC) monitoring of coagulopathy is available nowadays such as thrombolestometry (ROTEM), platelet function analyzer (PFA 200) and agregometry (Multiplate) to conduct administering of blood products or coagulation factors. The purpose of this study is to find out if POC management of bleeding and coagulopathy can reduce perioperative blood loss and consumption of blood products compared to standard approach. Methods Eighteen patients undergoing bilateral lung transplantation were randomized into 2 groups (from January 2018). In the first group (9 patients), management of bleeding and coagulopathy was done by anesthesiologist based on his clinical experience - standard approach, in the second group (9 patients), management of bleeding and coagulopathy was based on results of POC methods such as ROTEM, PFA 200, Multiplate. Results In POC group we found significantly reduced consumption of FFP and red blood cells during surgery and 24 hours after surgery. Also, perioperative blood loss was decreased in POC group comparing to standard approach group. Results are summarized in Table. Conclusion Management of bleeding and coagulopathy based on results of POC methods such as ROTEM, PFA 200 and Multiplate significantly reduces consumption of blood products and decreases perioperative blood loss, despite a small number of patients. [ABSTRACT FROM AUTHOR]