The Society of Thoracic Surgeons Adult Cardiac Surgery Database: 2021 Update on Echocardiography.

The Society of Thoracic Surgeons (STS) Adult Cardiac Surgery Database (ACSD) is the world's premier clinical outcomes registry for adult cardiac surgery and a driving force for quality improvement in cardiac surgery. Echocardiographic data provide a wealth of hemodynamic, structural, and functional data and have been part of STS ACSD data collection since its inception. An increasing body of evidence suggests that the use of echocardiography in patients undergoing cardiac surgery has a positive impact on postoperative outcomes. In this report, we describe and summarize the type and rate of reporting of echocardiography-related variables in the STS ACSD, including the Adult Cardiac Anesthesiology Module, from July 2017 to December 2019 for the most frequently performed cardiac surgical procedures. With this review, we aim to increase awareness of the importance of collecting accurate and consistent echocardiography data in the STS ACSD and to highlight opportunities for growth and improvement.

The Adult Cardiac Anesthesiology Section of STS Adult Cardiac Surgery Database: 2020 Update on Quality and Outcomes.

The Society of Cardiovascular Anesthesiologists, in partnership with The Society of Thoracic Surgeons, has developed the Adult Cardiac Anesthesiology Section of the Adult Cardiac Surgery Database. The goal of this landmark collaboration is to advance clinical care, quality, and knowledge, and to demonstrate the value of cardiac anesthesiology in the perioperative care of cardiac surgical patients. Participation in the Adult Cardiac Anesthesiology Section has been optional since its inception in 2014 but has progressively increased. Opportunities for further growth and improvement remain. In this first update report on quality and outcomes of the Adult Cardiac Anesthesiology Section, we present an overview of the clinically significant anesthesia and surgical variables submitted between 2015 and 2018. Our review provides a summary of quality measures and outcomes related to the current practice of cardiothoracic anesthesiology. We also emphasize the potential for addressing high-impact research questions as data accumulate, with the overall goal of elucidating the influence of cardiac anesthesiology contributions to patient outcomes within the framework of the cardiac surgical team.

Utility of Suprasternal Transinnominate Artery for Alternate Access in Transcatheter Aortic Valve Replacement.

OBJECTIVE: Despite advancements in transcatheter aortic valve replacement (TAVR) technology, alternate access strategies are still required when transfemoral access is unsuitable. In these often anatomically complex group of patients, we sought to evaluate the safety and feasibility of suprasternal transinnominate (TI) artery access for TAVR. METHODS: At our institution, 652 patients underwent TAVR from November 2011 through February 2020. Of these, 23 patients underwent TI TAVR via a 5-cm suprasternal incision without special instrumentation. Outcomes of interest were technical considerations, postoperative complications, and perioperative recovery in relation to established access strategies. RESULTS: The mean Society of Thoracic Surgeons risk score was 8.6 ± 4.2 and the average age was 75 ± 8. All patients underwent TI TAVR using a self-expanding (12), or balloon-expandable (11) transcatheter heart valve. Average postoperative stay was 2 ± 0.7 days (range 2 to 4) with most 20/23 (87%) being discharged to home. There was no 30-day mortality or readmission. There was 1 access-site complication and 1 cerebrovascular accident within 30 days, both intraoperative, with excellent recovery. All patients had either trivial (19) or mild (4) aortic regurgitation on 30-day echocardiography. CONCLUSIONS: TAVR via suprasternal TI access is feasible, safe, provides satisfactory perioperative recovery and adds to the options when patients require alternate access. Further data would be optimal to validate this single-center experience.

The Adult Cardiac Anesthesiology Section of STS Adult Cardiac Surgery Database: 2020 Update on Quality and Outcomes.

The Society of Cardiovascular Anesthesiologists, in partnership with The Society of Thoracic Surgeons, has developed the Adult Cardiac Anesthesiology Section of the Adult Cardiac Surgery Database. The goal of this landmark collaboration is to advance clinical care, quality, and knowledge, and to demonstrate the value of cardiac anesthesiology in the perioperative care of cardiac surgical patients. Participation in the Adult Cardiac Anesthesiology Section has been optional since its inception in 2014 but has progressively increased. Opportunities for further growth and improvement remain. In this first update report on quality and outcomes of the Adult Cardiac Anesthesiology Section, we present an overview of the clinically significant anesthesia and surgical variables submitted between 2015 and 2018. Our review provides a summary of quality measures and outcomes related to the current practice of cardiothoracic anesthesiology. We also emphasize the potential for addressing high-impact research questions as data accumulate, with the overall goal of elucidating the influence of cardiac anesthesiology contributions to patient outcomes within the framework of the cardiac surgical team.

Female rule in lemurs is ancestral and hormonally mediated.

Female social dominance (FSD) over males is unusual in mammals, yet characterizes most Malagasy lemurs, which represent almost 30% of all primates. Despite its prevalence in this suborder, both the evolutionary trajectory and proximate mechanism of FSD remain unclear. Potentially associated with FSD is a suite of behavioural, physiological and morphological traits in females that implicates (as a putative mechanism) 'masculinization' via androgen exposure; however, relative to conspecific males, female lemurs curiously show little evidence of raised androgen concentrations. By observing mixed-sex pairs of related Eulemur species, we identified two key study groups--one comprised of species expressing FSD and increased female scent marking, the other comprised of species (from a recently evolved clade) showing equal status between the sexes and the more traditional pattern of sexually dimorphic behaviour. Comparing females from these two groups, we show that FSD is associated with more masculine androgen profiles. Based on the widespread prevalence of male-like features in female lemurs and a current phylogeny, we suggest that relaxation of hormonally mediated FSD emerged only recently and that female masculinization may be the ancestral lemur condition, an idea that could revolutionize our understanding of the ancient socioecology and evolution of primate social systems.

Obesity is associated with neutrophil dysfunction and attenuation of murine acute lung injury.

Although obesity is implicated in numerous health complications leading to increased mortality, the relationship between obesity and outcomes for critically ill patients appears paradoxical. Recent studies have reported better outcomes and lower levels of inflammatory cytokines in obese patients with acute lung injury (ALI)/acute respiratory distress syndrome, suggesting that obesity may ameliorate the effects of this disease. We investigated the effects of obesity in leptin-resistant db/db obese and diet-induced obese mice using an inhaled LPS model of ALI. Obesity-associated effects on neutrophil chemoattractant response were examined in bone marrow neutrophils using chemotaxis and adoptive transfer; neutrophil surface levels of chemokine receptor CXCR2 were determined by flow cytometry. Airspace neutrophilia, capillary leak, and plasma IL-6 were all decreased in obese relative to lean mice in established lung injury (24 h). No difference in airspace inflammatory cytokine levels was found between obese and lean mice in both obesity models during the early phase of neutrophil recruitment (2-6 h), but early airspace neutrophilia was reduced in db/db obese mice. Neutrophils from uninjured obese mice demonstrated diminished chemotaxis to the chemokine keratinocyte cytokine compared with lean control mice, and adoptive transfer of obese mouse neutrophils into injured lean mice revealed a defect in airspace migration of these cells. Possibly contributing to this defect, neutrophil CXCR2 expression was significantly lower in obese db/db mice, and a similar but nonsignificant decrease was seen in diet-induced obese mice. ALI is attenuated in obese mice, and this blunted response is in part attributable to an obesity-associated abnormal neutrophil chemoattractant response.

Slam haplotypes modulate the response to lipopolysaccharide in vivo through control of NKT cell number and function.

CD1d-restricted NKT cells make up an innate-like T cell subset that plays a role in amplifying the response of innate immune leukocytes to TLR ligands. The Slam locus contains genes that have been implicated in innate and adaptive immune responses. In this study, we demonstrate that divergent Slam locus haplotypes modulate the response of macrophages to the TLR4 ligand LPS through their control of NKT cell number and function. In response to LPS challenge in vivo, macrophage TNF production in Slam haplotype-2(+) 129S1/SvImJ and 129X1/SvJ mice was significantly impaired in comparison with macrophage TNF production in Slam haplotype-1(+) C57BL/6J mice. Although no cell-intrinsic differences in macrophage responses to LPS were observed between strains, 129 mice were found to be deficient in liver NKT cell number, in NKT cell cytokine production in response to the CD1d ligand alpha-galactosylceramide, and in NKT cell IFN-gamma production after LPS challenge in vivo. Using B6.129c1 congenic mice and adoptive transfer, we found that divergent Slam haplotypes controlled the response to LPS in vivo, as well as the diminished NKT cell number and function, and that these phenotypes were associated with differential expression of signaling lymphocytic activation molecule family receptors on NKT cells. These data suggest that the polymorphisms that distinguish two Slam haplotypes significantly modulate the innate immune response in vivo through their effect on NKT cells.

Plasma granulocyte colony-stimulating factor levels correlate with clinical outcomes in patients with acute lung injury.

OBJECTIVES: To evaluate the association between plasma granulocyte colony-stimulating factor (G-CSF) levels and clinical outcomes including mortality in patients with acute lung injury (ALI), and to determine whether lower tidal volume ventilation was associated with a more rapid decrease in plasma G-CSF over time in patients with ALI. DESIGN: Retrospective measurement of G-CSF levels in plasma samples that were collected prospectively as part of a large multicenter clinical trial. SETTING: Intensive care units in ten university centers. PATIENTS: The study included 645 patients enrolled in the National Heart, Lung, and Blood Institute Acute Respiratory Distress Syndrome Clinical Network trial of lower tidal volumes compared with traditional tidal volumes for ALI. MEASUREMENTS AND MAIN RESULTS: Baseline plasma levels of G-CSF were associated with an increased risk of death and a decrease in ventilator-free days and organ failure-free days in multivariate analyses controlling for ventilation strategy, age, and sex (Odds ratio death 1.2/log10 increment G-CSF, 95% confidence interval 1.01 to 1.4). Stratification of G-CSF levels into quartiles revealed a strong association between the highest levels of G-CSF and an increased risk of death and decreased ventilator-free days and organ failure-free days in multivariate analyses controlling for ventilation strategy, Acute Physiology and Chronic Health Evaluation III score, Pao2/Fio2 ratio, creatinine, and platelet count (p < 0.05). Subgroup multivariate analysis of patients with sepsis as their risk factor for ALI revealed a U-shaped association between mortality and G-CSF levels such that risk increased linearly from the second through fourth (highest) quartiles, yet also increased in the first (lowest) quartile. G-CSF levels decreased over time in both tidal volume groups, and there was no statistical difference in the extent of decrease between ventilator strategies. CONCLUSIONS: In patients with ALI, plasma G-CSF levels are associated with morbidity and mortality, but these levels are not influenced by tidal volume strategy. In patients with sepsis-related ALI, a bimodal association between baseline plasma G-CSF levels and subsequent morbidity and mortality from this disease was found.

Crosstalk between CXCR4/stromal derived factor-1 and VLA-4/VCAM-1 pathways regulates neutrophil retention in the bone marrow.

Neutrophil retention in and release from the bone marrow is a critical process that remains incompletely understood. Previous work has implicated the CXCR4/stromal derived factor-1 (SDF-1) chemokine axis in the marrow retention of neutrophils, yet the adhesion pathways responsible for this retention are unknown. Because alpha(4)beta(1) integrin (VLA-4) and its ligand VCAM-1 play a central role in the interactions of hematopoietic stem cells, lymphocytes, and developing neutrophils in the marrow, we investigated whether this integrin might be involved in marrow neutrophil retention and release. In this study, we show that VLA-4 is expressed on murine marrow neutrophils and decreases with maturation, whereas blockade of this integrin leads to the release of marrow neutrophils. Marrow neutrophils adhere via VLA-4 to VCAM-1, which is expressed on marrow endothelium and stroma, and inhibition of VCAM-1 causes release of marrow neutrophils. Furthermore, SDF-1 (CXCL12) signaling through neutrophil CXCR4 augments VLA-4 adhesion to VCAM-1 in vitro, an effect that is blocked by preincubation with pertussis toxin. In vivo blockade of both CXCR4 and alpha(4) causes synergistic release of marrow neutrophils, showing that cross-talk between CXCR4 and VLA-4 modulates marrow retention of these cells. Taken together, these results indicate that the VLA-4/VCAM adhesion pathway is critical in the retention and maturation-controlled release of neutrophils from the marrow, while providing an important link between the CXCR4/SDF-1 signaling axis and the adhesion events that govern this process.

Pulmonary stromal-derived factor-1 expression and effect on neutrophil recruitment during acute lung injury.

The severe and protracted inflammation that characterizes acute lung injury (ALI) is driven by the ongoing recruitment of neutrophils to the lung. Although much of the cytokine signaling responsible for the initial phase of ALI has been elaborated, relatively little is known about the mechanisms governing the recruitment of neutrophils from the bone marrow to the lung in the later period of this disease. Given its previously described chemoattractant effects on marrow neutrophils, we investigated whether stromal-derived factor-1 (SDF-1) (CXCL12) might participate in this later phase of recruitment. Using immunohistochemistry to examine both banked human lung specimens from patients with ALI and lungs from mice with LPS-induced pneumonitis, we found that pulmonary SDF-1 expression increases during ALI. We further determined that both lung SDF-1 protein expression and mRNA expression rise in a delayed but sustained pattern in this mouse model and that the major source of the increase in expression appears to be the lung epithelium. Lastly, we found that expression of the SDF-1 receptor CXCR4 rises in a similar temporal pattern on neutrophils in both the blood and airspace of LPS-injured mice and that Ab-mediated SDF-1 blockade significantly attenuates late but not early pulmonary neutrophilia in this model. These results implicate SDF-1 in neutrophil recruitment to the lung in the later period of acute lung injury and suggest a novel role for this cytokine in coordinating the transition from the inflammatory response to the initiation of tissue repair.

Choosing the frequency of deep inflation in mice: balancing recruitment against ventilator-induced lung injury.

Low tidal volume (Vt) ventilation is protective against ventilator-induced lung injury but can promote development of atelectasis. Periodic deep inflation (DI) can open the lung, but if delivered too frequently may cause damage via repeated overdistention. We therefore examined the effects of varying DI frequency on lung mechanics, gas exchange, and biomarkers of injury in mice. C57BL/6 males were mechanically ventilated with positive end-expiratory pressure (PEEP) of 2 cmH2O for 2 h. One high Vt group received a DI with each breath (HV). Low Vt groups received 2 DIs after each hour of ventilation (LV) or 2 DIs every minute (LVDI). Control groups included a nonventilated surgical sham and a group receiving high Vt with zero PEEP (HVZP). Respiratory impedance was measured every 4 min, from which tissue elastance (H) and damping (G) were derived. G and H rose progressively during LV and HVZP, but returned to baseline after hourly DI during LV. During LVDI and HV, G and H remained low and gas exchange was superior to that of LV. Bronchoalveolar lavage fluid protein was elevated in HV and HVZP but was not different between LV and LVDI. Lung tissue IL-6 and IL-1beta levels were elevated in HVZP and lower in LVDI compared with LV. We conclude that frequent DI can safely improve gas exchange and lung mechanics and may confer protection from biotrauma. Differences between LVDI and HV suggest that an optimal frequency range of DI exists, within which the benefits of maintaining an open lung outweigh injury incurred from overdistention.

Role of the CXCR4/SDF-1 chemokine axis in circulating neutrophil homeostasis.

The bone marrow is the primary site for neutrophil production and release into the circulation. Because the CXC chemokine receptor-4/stromal derived factor-1 (CXCR4/SDF-1) axis plays a central role in the interactions of hematopoietic stem cells, lymphocytes, and developing neutrophils in the marrow, we investigated whether reciprocal CXCR4-dependent mechanisms might be involved in neutrophil release and subsequent return to the marrow following circulation. Neutralizing antibody to CXCR4 reduced marrow retention of infused neutrophils (45.7% +/- 0.5% to 6.9% +/- 0.5%) and was found to mobilize neutrophils from marrow (34.4% +/- 4.4%). Neutrophil CXCR4 expression and SDF-1-induced calcium flux decreased with maturation and activation of the cells, corresponding to the decreased marrow homing associated with these characteristics in vivo. Infusion of the inflammatory mediator and CXCR2 ligand KC led to mobilization of neutrophils from marrow by itself and was augmented 3-fold by low doses of CXCR4-blocking antibody that otherwise had no mobilizing effect. Examination of KC and SDF-1 calcium signaling demonstrated that the effect of KC may, in part, be due to heterologous desensitization to SDF-1. These results suggest that the CXCR4/SDF-1 axis is critical in circulating neutrophil homeostasis and that it may participate in the rapid release of neutrophils from the marrow during inflammation through a novel interaction with inflammatory CXC chemokines.