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Introduction: Sepsis is a frequent complication in critically ill patients. Patients may require control of the source of infection, removal of pathogens and damaged cells, and organ support. Often, these targets can be achieved through the utilization of extracorporeal therapies including hemoperfusion for the adsorption of cytokines and other circulating mediators. On extracorporeal organ support, patients are generally treated with antibiotic therapy, and vancomycin is one of the most commonly used antibiotics. Because of the aspecific nature of adsorption, antibiotics can be removed from the circulation, leading to altered plasma levels and requiring prescription adjustment. The aim was to define the amount of vancomycin adsorbed by a sorbent cartridge (HA380, Jafron, China) during hemoperfusion and to establish possible strategies to maintain an effective plasma level in critically ill patients undergoing extracorporeal therapies. Methods: In vitro experiments with incremental concentrations of vancomycin in the test solution (500 and 1,000 mL) were carried out in a recirculation circuit until sorbent saturation was observed. A maximum of 10 g of vancomycin were injected and mini-modules containing 25 g of dry resin were utilized. Results: In different experiments with various concentration of vancomycin, a maximum amount of 244 mg/g of sorbent was adsorbed reaching saturation between 60 and 80 min from the beginning of the experiments. The kinetics of adsorption appears to be governed by a Langmuir-like isotherm with maximal removal speed in the early minutes and a plateau after 60 min. Discussion/Conclusion: HA380 adsorbs significant amounts of vancomycin. Adjusting the achieved results with the experimental mini-module to a full-scale cartridge, a total of 25 g of antibiotic can be removed. This might have affected outcome results in clinical trials. This suggests prescribing administration to critically ill patients requiring hemoperfusion, immediately after or in the inter-session time window. In case of administration during hemoperfusion, adequate adjustment and plasma level monitoring is strongly recommended. [ABSTRACT FROM AUTHOR]

Introduction: Medium cutoff (MCO) membranes represent an interesting innovation in the field of hemodialysis. Given the correlation between large (PM >25 kDa) middle molecules (LMM) and clinical outcomes, the possibility to broaden the spectrum of solutes removed in hemodialysis with MCO membranes introduces a new perspective for end-stage kidney disease patients. Due to low diffusion coefficients of LMM, the use of convection is required to maximize extracorporeal clearance. High convective rates are achieved with high-flux membranes in hemodiafiltration, a technique not available in the US. In case of the MCO membrane, remarkable clearances of LMM are achieved combining the permeability of the membrane with a significant amount of internal convection. The mechanism of filtration-backfiltration inside the dialyzer enables effective removal of LMM in a technique called expanded hemodialysis (HDx). Given such theoretical explanation, it is important to demonstrate the blood and ultrafiltration rheology inside the MCO dialyzer. Method: This study for the first time describes flow dynamic parameters and internal cross-filtration, thanks to specific radiology and nuclear imaging techniques. Results: Flow dynamic analysis of the blood and dialysate compartment confirms excellent distribution of velocities and an excellent matching of blood and dialysate. Average blood flow velocity allows for wall shear rates adequate to avoid protein stagnation at the blood membrane interface and increase in blood viscosity. Cross-filtration analysis demonstrates a remarkable filtration/backfiltration flux reaching values >30 mL/min at a blood flow of 300 mL/min and zero net filtration. Conclusion: The MCO dialyzer Theranova 400 appears to have a design optimized to perform expanded hemodialysis (HDx). [ABSTRACT FROM AUTHOR]

Introduction: Cardiac surgery-associated acute kidney injury (CSA-AKI) is a common complication in patients undergoing cardiac surgery. Preoperative renal functional reserve (RFR) has been demonstrated to be highly predictive of CSA-AKI. We have previously demonstrated that intraparenchymal renal resistive index variation (IRRIV) measured by ultrasound (US) can identify the presence of RFR in healthy individuals. This study aimed (1) to examine the correlation between the US IRRIV test and RFR measured through the protein loading test in patients undergoing elective cardiac surgery and (2) to determine the value of the 2 methods for predicting occurrence of AKI or subclinical AKI after cardiac surgery. Methods: Consecutive patients scheduled for cardiac surgery were enrolled for this pilot study. The protein loading test and the IRRIV test were performed in all patients 2 days before cardiac surgery. Correlation between IRRIV and RFR was tested using Pearson correlation analysis. Association between presence of RFR and positive IRRIV test, presence of RFR and AKI and subclinical AKI, and positive IRRIV test and AKI and subclinical AKI was evaluated using logistic regression analysis. Receiver operating characteristic (ROC) curve analysis was performed to evaluate the values of IRRIV for predicting RFR, RFR for predicting AKI and subclinical AKI, and IRRIV for predicting AKI and subclinical AKI. Results: Among the 31 patients enrolled, significant association was found between IRRIV and RFR (r = 0.81; 95% CI: 0.63–0.90; p < 0.01). The association between RFR and IRRIV was described in 27/31 (87.1%) patients. The sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of the IRRIV test were 100, 84, 60, and 100%, respectively. In ROC curve analysis, the area under the curve (AUC) was 0.80 (95% CI: 0.64–0.96). After cardiac surgery, 1/31 (3.2%) patient had AKI and 12/31 (38.7%) had subclinical AKI. RFR predicted subclinical AKI (odds ratio [OR] = 0.93; 95% CI: 0.87–0.98; p = 0.02). The sensitivity, specificity, PPV, and NPV of the RFR were 61, 88.8, 80, and 76%, respectively; the AUC was 0.75 (95% CI: 0.59–0.91). IRRIV predicts subclinical AKI (OR = 0.79; 95% CI: 0.67–0.93; p = 0.005). The sensitivity, specificity, PPV, and NPV of the IRRIV test were 46.1, 100, 100, and 72%, respectively; the AUC was 0.73 (95% CI: 0.58–0.87). Conclusion: This pilot study suggests that a positive IRRIV test can significantly predict the presence of RFR in patients scheduled for cardiac surgery. RFR measured by the protein loading test or by the US IRRIV test can predict the occurrence of subclinical postoperative AKI. The findings of this study need to be confirmed in large patient cohorts. [ABSTRACT FROM AUTHOR]