Does training paradigm matter? A comparison of outcomes of frail patients treated by integrated vascular surgery residency and vascular surgery fellowship-trained surgeons.

BACKGROUND: It is unclear whether shortened training of integrated vascular surgery residencies (IVSR) has detrimental effects on graduates' performance. We sought to investigate whether there is a difference in frail patient outcomes based on the training paradigm completed by their surgeon. METHODS: IVSR and vascular surgery fellowship (VSF)-trained surgeons were identified in the American Board of Surgery database and linked to the Vascular Quality Initiative registry (2013-2019) to evaluate provider-specific patient outcomes for frail patients following vascular procedures using mixed-effects logistic regression. RESULTS: 105 IVSR graduates (31%) and 233 VSF graduates (69%) were included. Composite 1-year outcomes of frail patients were comparable between IVSR and VSF-trained surgeons following carotid endarterectomy (16%-IVSR vs 25%-VSF; p = 0.76), lower extremity revascularization (37%-IVSR vs 36%-VSF; p = 0.83), and aortic aneurysm repair (25%-IVSR vs 23%-VSF; p = 0.89). CONCLUSIONS: The type of training paradigm completed by vascular surgeons was not associated with differences in their post-operative outcomes in frail patients.

Minimally Invasive versus Full Sternotomy SAVR in the Era of TAVR: An Institutional Review.

In the era of advancing transcatheter aortic valve replacement (TAVR) technology, traditional open surgery remains a valuable intervention for patients who are not TAVR candidates. We sought to compare perioperative variables and postoperative outcomes of minimally invasive and full sternotomy surgical aortic valve replacement (SAVR) at a single institution. A retrospective analysis of 113 patients who underwent isolated SAVR via full sternotomy or upper hemi-sternotomy between January 2015 and December 2019 at the University of Utah Hospital was performed. Preoperative comorbidities and demographic information were not different among groups, with the exception of diabetes, which was significantly more common in the full sternotomy group (p = 0.01). Median procedure length was numerically shorter in the minimally invasive group but was not significant following the Bonferroni correction (p = 0.047). Other perioperative variables were not significantly different. The two groups showed no difference in the incidence of postoperative adverse events (p = 0.879). As such, minimally invasive SAVR via hemi-sternotomy remains a safe and effective alternative to full sternotomy for patients who meet the criteria for aortic valve replacement.

Rhodium-catalyzed enantioselective silylation of arene C-H bonds: desymmetrization of diarylmethanols.

We report a Rh-catalyzed, enantioselective silylation of arene C-H bonds directed by a (hydrido)silyl group. (Hydrido)silyl ethers that are formed in situ by hydrosilylation of benzophenone or its derivatives undergo asymmetric C-H silylation in high yield with excellent enantioselectivity in the presence of [Rh(cod)Cl]2 and a chiral bisphosphine ligand. The stereoselectivity of this process also allows enantioenriched diarylmethanols to react with site selectivity at one aryl group over the other. Enantioenriched benzoxasiloles from the silylation process undergo a range of transformations to form C-C, C-O, C-I, or C-Br bonds.

Enantioselective construction of quaternary stereogenic carbon atoms by the Lewis base catalyzed additions of silyl ketene imines to aldehydes.

Silyl ketene imines derived from a variety of α-branched nitriles have been developed as highly useful reagents for the construction of quaternary stereogenic centers via the aldol addition reaction. In the presence of SiCl4 and the catalytic action of a chiral phosphoramide, silyl ketene imines undergo extremely rapid and high yielding addition to a wide variety of aromatic aldehydes with excellent diastereo- and enantioselectivity. Of particular note are the high yields and selectivities obtained from electron-rich, electron-poor, and hindered aldehydes. Linear aliphatic aldehydes did react with good diastereo- and enantioselectivity in the presence of nBu4N(+)I(-), but branched aldehydes were much less reactive. Semiempirical calculations provided a rationalization of the observed diastereo- and enantioselectivity via open transitions states.

Silyl ketene imines: highly versatile nucleophiles for catalytic, asymmetric synthesis.

This Minireview provides an overview on the development of silyl ketene imines and their recent applications in catalytic, enantioselective reactions. The unique structure of the ketene imine allows a diverse range of reactivity patterns and provides solutions to existing challenges in the enantioselective construction of quaternary stereogenic carbon centers and cross-benzoin adducts. A variety of reactions for which silyl ketene imines have been applied are presented with an overall goal of inspiring new uses for these underutilized nucleophiles.

N-silyl oxyketene imines are underused yet highly versatile reagents for catalytic asymmetric synthesis.

The reactions of acyl anion equivalents (d1 synthons) with carbonyl electrophiles allow for the construction of a wide range of molecules useful for the synthesis of biologically active compounds, natural products and chiral ligands. Despite their utility, significant challenges still exist for developing catalytic, enantioselective variants of these reactions. For example, the asymmetric benzoin process, arguably the most characteristic reaction of d synthetic equivalents, finds no general solution for reactions involving aliphatic acyl anions. In this Article, we introduce a new class of stable, isolable silyl ketene imines derived from protected cyanohydrins. These nucleophiles serve as acyl anion equivalents in Lewis base catalysed aldol addition reactions and allow for the preparation of cross-benzoin and glycolate-aldol products in high yield and with exceptional diastereo- and enantioselectivities.

Enantioselective construction of quaternary stereogenic carbons by the Lewis base catalyzed additions of silyl ketene imines to aldehydes.

Silyl ketene imines derived from a variety of alpha-branched nitriles have been developed as highly useful reagents for the construction of quaternary stereogenic centers via the aldol addition reaction. In the presence of SiCl4 and the catalytic action of chiral phosphoramide (R,R)-5, silyl ketene imines undergo extremely rapid and high yielding addition to a wide variety of aromatic aldehydes with excellent diastereo- and enantioselectivity. Of particular note is the high yields and selectivities obtained from electron-rich, electron-poor, and hindered aldehydes. The nitrile function serves as a useful precursor for further synthetic manipulation.