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Background: Intraoperative antifibrinolytic drug administration is a safe and effective method of reducing blood loss and allogenic transfusions in patients undergoing spine deformity correction. Aim: This study aimed to compare the effectiveness of two antifibrinolytic drugs tranexamic acid (TXA) and epsilon amino caproic acid (EACA) in reducing peri-operative blood loss and transfusion requirements against a placebo control in patients with idiopathic scoliosis undergoing correction surgery. Setting and Design: This is a prospective, randomized, double-blinded, controlled comparative study. Methodology: Patients in TXA group received 50 mg.kg−1 bolus and 10 mg.kg−1.h−1 infusion as against 100 mg.kg−1 and 10 mg.kg−1.h−1 infusion in EACA group. The placebo group had saline bolus and infusion. Parameters observed included baseline demographic and deformity data, duration of surgery, total peri-operative blood loss, and allogenic packed red cell transfusion requirements. Statistical Analysis: Mean and standard deviation were used to represent the quantitative continuous data, and percentage was used to represent categorical data. The Student's t-test and ANOVA were used to compare means between groups. Bonferroni's multiple comparison test was used to find out the association between categorical variables. Results: A total of 36 patients were enrolled with 12 patients in each group. Peri-operative blood loss was 50.1% lower in patients receiving TXA and 17.7% lower in patients receiving EACA compared with the placebo group. The volume of total packed red cell transfusion was 66.7% lower in patients receiving TXA and 45.6% lower in patients receiving EACA compared with placebo. Conclusion: TXA was more effective in reducing total peri-operative blood loss and allogenic transfusion requirement in idiopathic scoliosis correction surgery compared to EACA.

The modular multilevel converter (MMC) is one of the upcoming converters with a scalable technology that enables high voltage and high power capabilities. MMC construction mainly contains power electronics building blocks (PEBBs) on the upper and lower arm for each phase. PEBB consists of a capacitor, transistor and diode. As the capacitor voltage ripple of the traditional MMC is directly proportional to the output torque and inversely proportional to the motor speed, for high torque, low-speed application ripples will be high. Due to this drawback, widespread application in medium-speed motor drives has not been achieved. To overcome this, hybrid MMC has been proposed where a series switch is also introduced in traditional MMC to control the circulating current. The paper implements level shift pulse width modulation control (LSPWM) for the hybrid MMC to decrease the voltage ripple produced by the capacitor. LSPWM has been chosen in this paper mainly due to the simplicity of calculation involved with this control scheme and comparison to the other existing techniques. This control scheme also helps in the reduction of the total harmonic distortion (THD). As solar PV system is a promising green resource, the MMC can be fed by solar panels. The principle of operation of the hybrid MMC topology with LSPWM is explained in this paper. The simulation results carried out in MATLAB/Simulink verify the proposed topology.

Traditionally, deceased donor liver grafts receive dual perfusion (DP) through the portal vein and the hepatic artery (HA) either in situ or on the back table. HA perfusion is avoided in living donor liver grafts for fear of damage to the intima and consequent risk of hepatic artery thrombosis (HAT). However, biliary vasculature is predominantly derived from the HA. We hypothesized that antegrade perfusion of the HA in addition to the portal vein on the back table could reduce the incidence of postoperative biliary complications. Consecutive adult patients undergoing living donor liver transplantations were randomized after donor hepatectomy to receive graft perfusion of histidine-tryptophan-ketoglutarate solution either via both the HA and portal vein (DP group, n = 62) or only through the portal vein (standard perfusion [SP] group, n = 62). The primary endpoint was the occurrence of biliary complications (biliary leak/stricture). Secondary endpoints included HAT and patient survival. The incidence of biliary stricture was significantly lower in the DP group (6.5% versus 19.4%; odds ratio, 0.29; 95% confidence interval, 0.09-0.95; P = 0.04). There was no significant reduction in the incidence of HAT, bile leak, or hospital stay between the 2 groups. The 3-year mortality and graft survival rates were significantly higher among patients who received DP compared with SP (P = 0.004 and P = 0.003, respectively). On multivariate analysis, nonperfusion of the HA and preceding bile leak were found to be risk factors for the development of biliary stricture (P = 0.04 and P < 0.001, respectively). In conclusion, DP of living donor liver grafts through both the HA and portal vein on the back table may protect against the development of biliary stricture. This could translate to improved patient survival in the short term.