Percutaneous endovascular abdominal aortic aneurysm repair with monitored anesthesia care decreases operative time but not pulmonary complications

Objectives To report our experience and compare the results of percutaneous endovascular aortic aneurysm repair (PEVAR) performed under monitored anesthesia care (MAC) to PEVAR under general anesthesia (GA). Methods A retrospective review of patients who underwent non-emergency endovascular abdominal aortic aneurysm repair (EVAR) was completed. Patients were excluded if they had a complex repair, including fenestrated, branched, or parallel endografting. Demographics, operative data, 30-day mortality/morbidity and postoperative outcomes were analyzed. Results A total of 159 patients were identified with a median age of 69. 115 patients had PEVAR, 45 (39.1%) PEVAR MAC and 70 (60.9%) PEVAR GA. PEVAR MAC compared to PEVAR GA had decreased operative time (106 vs. 134 min, P < 0.001), time in the operating room (163 vs. 245 min, P = 0.016), and estimated blood loss (EBL) (115 vs. 176 mL P = 0.012). There was no statistically significant difference in the hospital length of stay (LOS) (1.9 vs. 2.7 days, P = 0.133), and post-operative complications including pulmonary (2.2 vs. 2.9%, P = 0.835). Forty-four patients had EVAR with a femoral cutdown (FC), including 14 PEVAR conversions. PEVAR conversion was associated with higher EBL (543 vs. 323 mL, P = 0.03), operative time (230 vs. 178 min, P = 0.01), and operating room time (307 vs. 275 min, P = 0.01) compared to planned EVAR with FC. Conclusions PEVAR under MAC is associated with shorter time in the operating room compared to PEVAR under GA. PEVAR under MAC does however not decrease overall morbidities, including postoperative pulmonary complications

Fast Au-Ni@ZIF-8-catalyzed ammonia borane hydrolysis boosted by dramatic volcano-type synergy and plasmonic acceleration

Production of hydrogen (H2) from H2 storage materials is very attractive as a source of sustainable energy. We report that AuNi@ZIF-8 alloys are very efficient nanocatalysts for H2 evolution upon ammonia borane hydrolysis under visible-light illumination with turnover frequency 3.4 times higher than with the monometallic Ni catalyst in the dark. This improvement is attributed to dramatic volcano-type positive synergy optimized in Au0.5Ni0.5 @ZIF-8, for which ZIF-8 is by far the superior support, as well as to the localized surface plasmon resonance induced between 450 and 620 nm. Infrared spectra analysis and tandem reaction confirm the origin of the hydrogen atoms, reveal the reaction mechanism, and suggest how the cleavage of the B–H and O–H bonds proceeds in this reaction. Deuteration experiments with D2O including primary kinetic isotope effects and density functional theory calculation under both dark and visible light conditions show that activation of H2O always is the rate-determining step

Visible-Light Acceleration of H 2 Evolution from Aqueous Solutions of Inorganic Hydrides Catalyzed by Gold-Transition-Metal Nanoalloys

International audienceProduction of hydrogen (H2) upon hydrolysis of inorganic hydrides potentially is a key step in green energy production. We find that visible-light irradiation of aqueous solutions of ammonia-borane (AB) or NaBH4 containing “click”-dendrimer-stabilized alloyed nanocatalysts composed of nanogold and another late transition-metal nanoparticle (LTMNP) highly enhances catalytic activity for H2 generation while also inducing alloy to Au core@M shell nanocatalyst restructuration. In terms of visible-light-induced acceleration of H2 production from both AB and NaBH4, the Au1Ru1 alloy catalysts show the most significant light-boosting effect. Au–Rh and Au–PtNPs are also remarkable with total H2 release time from AB and NaBH4 down to 1.3 min at 25 °C (AuRh), 3 times less than in the dark, and Co is the best earth-abundant metal alloyed with nanogold. This boosting effect is explained by the transfer of plasmon-induced hot electron from the Au atoms to the LTMNP atoms facilitating water O–H oxidative addition on the LTMNP surface, as shown by the large primary kinetic isotope effect kH/kD upon using D2O obtained for both AB and NaBH4. The second simultaneous and progressive effect of visible-light irradiation during these reactions, alloy to Au core@M shell restructuration, enhances the catalytic activity in the recycling, because, in the resulting Au core@M shell, the surface metal (such as Ru) is much more active than the original Au-containing alloy surface in dark reactions. There is no light effect on the rate of hydrogen production for the recycled nanocatalyst because of the absence of Au on the NP surface, but it is still very efficient in hydrogen release during four cycles because of the initial light-induced restructuration, although it is slightly less efficient than the original nanoalloy in the presence of light. The dendritic triazole coordination on each LTMNP surface appears to play a key role in these remarkable light-induced processes