Efficacy and Safety of Perioperative Angiotensin II Versus Phenylephrine as a First-Line Continuous Infusion Vasopressor in Kidney Transplant Recipients.

INTRODUCTION: Angiotensin II (ATII) maintains blood pressure via RAAS with a beneficial adverse effect profile versus catecholamines and phenylephrine. Head-to-head data comparing ATII to phenylephrine are lacking regarding renal allograft function, hemodynamic efficacy, and safety within the perioperative period of kidney transplantation. METHODS: This single-center, retrospective study included adult kidney transplant recipients who received continuous infusions of ATII or phenylephrine within a 24-h perioperative period as a first-line vasopressor according to an institutional algorithm. The primary endpoint was allograft function. Secondary endpoints were hemodynamic efficacy and adverse effects. RESULTS: Among 105 patients, there was no significant difference in IGF (p = 0.545), SGF (p = 0.557), or DGF (p = 0.878) between patient cohorts. In the 34 patients with cold ischemia time (CIT) > 14-h, IGF was higher (p = 0.013) and DGF (p = 0.045) was lower in the ATII cohort versus phenylephrine. In all patients, ATII was associated with a decreased need for additional vasopressor agents (p < 0.001). Adverse effect profiles were similar between cohorts (p > 0.05). CONCLUSION: Among kidney transplant recipients, ATII may be a suitable first-line alternative compared with phenylephrine in the perioperative period for hypotension management with a reduced need for additional vasopressor support. Allograft benefits were observed in patients with prolonged CIT.

Evaluation of a patient specific, targeted-intensity pharmacologic thromboprophylaxis protocol in hospitalized patients with COVID-19.

Patients with COVID-19 are at higher risk of thrombosis due to the inflammatory nature of their disease. A higher-intensity approach to pharmacologic thromboprophylaxis may be warranted. The objective of this retrospective cohort study was to determine if a patient specific, targeted-intensity pharmacologic thromboprophylaxis protocol incorporating severity of illness, weight, and biomarkers decreased incidence of thrombosis in hospitalized patients with COVID-19. Included patients were hospitalized with COVID-19 and received thromboprophylaxis within 48 h of admission. Exclusion criteria included receipt of therapeutic anticoagulation prior to or within 24 h of admission, history of heparin-induced thrombocytopenia, extracorporeal membrane oxygenation, pregnancy, or incarceration. Per-protocol patients received thromboprophylaxis according to institutional protocol involving escalated doses of anticoagulants based upon severity of illness, total body weight, and biomarker thresholds. The primary outcome was thrombosis. Secondary outcomes included major bleeding, mortality, and identification of risk factors for thrombosis. Of 1189 patients screened, 803 were included in the final analysis. The median age was 54 (42-65) and 446 (55.5%) were male. Patients in the per-protocol group experienced significantly fewer thrombotic events (4.4% vs. 10.7%, p = 0.002), less major bleeding (3.1% vs. 9.6%, p < 0.001), and lower mortality (6.3% vs. 11.8%, p = 0.02) when compared to patients treated off-protocol. Significant predictors of thrombosis included mechanical ventilation and male sex. Post-hoc regression analysis identified mechanical ventilation, major bleeding, and D-dimer ≥ 1500 ng/mL FEU as significant predictors of mortality. A targeted pharmacologic thromboprophylaxis protocol incorporating severity of illness, body weight, and biomarkers appears effective and safe for preventing thrombosis in patients with COVID-19.

A suite of rare microbes interacts with a dominant, heritable, fungal endophyte to influence plant trait expression.

Endophytes are microbes that live, for at least a portion of their life history, within plant tissues. Endophyte assemblages are often composed of a few abundant taxa and many infrequently observed, low-biomass taxa that are, in a word, rare. The ways in which most endophytes affect host phenotype are unknown; however, certain dominant endophytes can influence plants in ecologically meaningful ways-including by affecting growth and immune system functioning. In contrast, the effects of rare endophytes on their hosts have been unexplored, including how rare endophytes might interact with abundant endophytes to shape plant phenotype. Here, we manipulate both the suite of rare foliar endophytes (including both fungi and bacteria) and Alternaria fulva-a vertically transmitted and usually abundant fungus-within the fabaceous forb Astragalus lentiginosus. We report that rare, low-biomass endophytes affected host size and foliar %N, but only when the heritable fungal endophyte (A. fulva) was not present. A. fulva also reduced plant size and %N, but these deleterious effects on the host could be offset by a negative association we observed between this heritable fungus and a foliar pathogen. These results demonstrate how interactions among endophytic taxa determine the net effects on host plants and suggest that the myriad rare endophytes within plant leaves may be more than a collection of uninfluential, commensal organisms, but instead have meaningful ecological roles.