Elective Cancer Surgery in COVID-19-Free Surgical Pathways During the SARS-CoV-2 Pandemic: An International, Multicenter, Comparative Cohort Study.

PURPOSE: As cancer surgery restarts after the first COVID-19 wave, health care providers urgently require data to determine where elective surgery is best performed. This study aimed to determine whether COVID-19-free surgical pathways were associated with lower postoperative pulmonary complication rates compared with hospitals with no defined pathway. PATIENTS AND METHODS: This international, multicenter cohort study included patients who underwent elective surgery for 10 solid cancer types without preoperative suspicion of SARS-CoV-2. Participating hospitals included patients from local emergence of SARS-CoV-2 until April 19, 2020. At the time of surgery, hospitals were defined as having a COVID-19-free surgical pathway (complete segregation of the operating theater, critical care, and inpatient ward areas) or no defined pathway (incomplete or no segregation, areas shared with patients with COVID-19). The primary outcome was 30-day postoperative pulmonary complications (pneumonia, acute respiratory distress syndrome, unexpected ventilation). RESULTS: Of 9,171 patients from 447 hospitals in 55 countries, 2,481 were operated on in COVID-19-free surgical pathways. Patients who underwent surgery within COVID-19-free surgical pathways were younger with fewer comorbidities than those in hospitals with no defined pathway but with similar proportions of major surgery. After adjustment, pulmonary complication rates were lower with COVID-19-free surgical pathways (2.2% v 4.9%; adjusted odds ratio [aOR], 0.62; 95% CI, 0.44 to 0.86). This was consistent in sensitivity analyses for low-risk patients (American Society of Anesthesiologists grade 1/2), propensity score-matched models, and patients with negative SARS-CoV-2 preoperative tests. The postoperative SARS-CoV-2 infection rate was also lower in COVID-19-free surgical pathways (2.1% v 3.6%; aOR, 0.53; 95% CI, 0.36 to 0.76). CONCLUSION: Within available resources, dedicated COVID-19-free surgical pathways should be established to provide safe elective cancer surgery during current and before future SARS-CoV-2 outbreaks

Elective cancer surgery in COVID-19-free surgical pathways during the SARS-CoV-2 pandemic: An international, multicenter, comparative cohort study

PURPOSE As cancer surgery restarts after the first COVID-19 wave, health care providers urgently require data to determine where elective surgery is best performed. This study aimed to determine whether COVID-19–free surgical pathways were associated with lower postoperative pulmonary complication rates compared with hospitals with no defined pathway. PATIENTS AND METHODS This international, multicenter cohort study included patients who underwent elective surgery for 10 solid cancer types without preoperative suspicion of SARS-CoV-2. Participating hospitals included patients from local emergence of SARS-CoV-2 until April 19, 2020. At the time of surgery, hospitals were defined as having a COVID-19–free surgical pathway (complete segregation of the operating theater, critical care, and inpatient ward areas) or no defined pathway (incomplete or no segregation, areas shared with patients with COVID-19). The primary outcome was 30-day postoperative pulmonary complications (pneumonia, acute respiratory distress syndrome, unexpected ventilation). RESULTS Of 9,171 patients from 447 hospitals in 55 countries, 2,481 were operated on in COVID-19–free surgical pathways. Patients who underwent surgery within COVID-19–free surgical pathways were younger with fewer comorbidities than those in hospitals with no defined pathway but with similar proportions of major surgery. After adjustment, pulmonary complication rates were lower with COVID-19–free surgical pathways (2.2% v 4.9%; adjusted odds ratio [aOR], 0.62; 95% CI, 0.44 to 0.86). This was consistent in sensitivity analyses for low-risk patients (American Society of Anesthesiologists grade 1/2), propensity score–matched models, and patients with negative SARS-CoV-2 preoperative tests. The postoperative SARS-CoV-2 infection rate was also lower in COVID-19–free surgical pathways (2.1% v 3.6%; aOR, 0.53; 95% CI, 0.36 to 0.76). CONCLUSION Within available resources, dedicated COVID-19–free surgical pathways should be established to provide safe elective cancer surgery during current and before future SARS-CoV-2 outbreaks

Multi-messenger observations of a binary neutron star merger

On 2017 August 17 a binary neutron star coalescence candidate (later designated GW170817) with merger time 12:41:04 UTC was observed through gravitational waves by the Advanced LIGO and Advanced Virgo detectors. The Fermi Gamma-ray Burst Monitor independently detected a gamma-ray burst (GRB 170817A) with a time delay of ~1.7 s with respect to the merger time. From the gravitational-wave signal, the source was initially localized to a sky region of 31 deg2 at a luminosity distance of 40+8-8 Mpc and with component masses consistent with neutron stars. The component masses were later measured to be in the range 0.86 to 2.26 Mo. An extensive observing campaign was launched across the electromagnetic spectrum leading to the discovery of a bright optical transient (SSS17a, now with the IAU identification of AT 2017gfo) in NGC 4993 (at ~40 Mpc) less than 11 hours after the merger by the One- Meter, Two Hemisphere (1M2H) team using the 1 m Swope Telescope. The optical transient was independently detected by multiple teams within an hour. Subsequent observations targeted the object and its environment. Early ultraviolet observations revealed a blue transient that faded within 48 hours. Optical and infrared observations showed a redward evolution over ~10 days. Following early non-detections, X-ray and radio emission were discovered at the transient’s position ~9 and ~16 days, respectively, after the merger. Both the X-ray and radio emission likely arise from a physical process that is distinct from the one that generates the UV/optical/near-infrared emission. No ultra-high-energy gamma-rays and no neutrino candidates consistent with the source were found in follow-up searches. These observations support the hypothesis that GW170817 was produced by the merger of two neutron stars in NGC4993 followed by a short gamma-ray burst (GRB 170817A) and a kilonova/macronova powered by the radioactive decay of r-process nuclei synthesized in the ejecta

Effects of hospital facilities on patient outcomes after cancer surgery: an international, prospective, observational study

Background Early death after cancer surgery is higher in low-income and middle-income countries (LMICs) compared with in high-income countries, yet the impact of facility characteristics on early postoperative outcomes is unknown. The aim of this study was to examine the association between hospital infrastructure, resource availability, and processes on early outcomes after cancer surgery worldwide.Methods A multimethods analysis was performed as part of the GlobalSurg 3 study-a multicentre, international, prospective cohort study of patients who had surgery for breast, colorectal, or gastric cancer. The primary outcomes were 30-day mortality and 30-day major complication rates. Potentially beneficial hospital facilities were identified by variable selection to select those associated with 30-day mortality. Adjusted outcomes were determined using generalised estimating equations to account for patient characteristics and country-income group, with population stratification by hospital.Findings Between April 1, 2018, and April 23, 2019, facility-level data were collected for 9685 patients across 238 hospitals in 66 countries (91 hospitals in 20 high-income countries; 57 hospitals in 19 upper-middle-income countries; and 90 hospitals in 27 low-income to lower-middle-income countries). The availability of five hospital facilities was inversely associated with mortality: ultrasound, CT scanner, critical care unit, opioid analgesia, and oncologist. After adjustment for case-mix and country income group, hospitals with three or fewer of these facilities (62 hospitals, 1294 patients) had higher mortality compared with those with four or five (adjusted odds ratio [OR] 3.85 [95% CI 2.58-5.75]; p<0.0001), with excess mortality predominantly explained by a limited capacity to rescue following the development of major complications (63.0% vs 82.7%; OR 0.35 [0.23-0.53]; p<0.0001). Across LMICs, improvements in hospital facilities would prevent one to three deaths for every 100 patients undergoing surgery for cancer.Interpretation Hospitals with higher levels of infrastructure and resources have better outcomes after cancer surgery, independent of country income. Without urgent strengthening of hospital infrastructure and resources, the reductions in cancer-associated mortality associated with improved access will not be realised

Endoscopic method for obtaining gastric and colorectal mucosa for LDH isoensymes determination

Les auteurs décrivent une méthode de prélèvements de muqueuse gastrique ou coloreclale en vue de la détermination électrophorétique des isoezymes LDH. La méthode nécessite au moins dix prélèvements biopsiques, gastriques ou coliques par voie fibroendoscopique. En raison de la taille plus grande des échantillons tissulaires, une seule biopsie rectale obtenue par proctosigmoïdoscope rigide est suffisante. La valeur clinique des dosages des isoezyines LDH concerne principalement la surveillance des lésions précancéreuses, le diagnostic précoce du cancer et l'évaluation des rechutes après traitement chirurgical

Towards covariance realism in batch least-squares orbit determination

Regular products within the field of Space Surveillance and Tracking (SST) and Space Traffic Management (STM), such as high-risk collisions, upcoming re-entries or fragmentations, rely both on the estimated state and associated uncertainty of detectable resident space objects (RSOs). Classical orbit determination (OD) algorithms provide the required estimations, assuming that the uncertainty in the state of the object is properly characterized by its state vector covariance and assuming Gaussian processes. However, a common problem of classical orbit determination processes is the misrepresentation of the RSOs uncertainty through the estimated covariance. Ultimately, this causes a great impact in the quality and accuracy of SST products as the estimated covariance is overly optimistic (too small) and the true uncertainty of the object is not captured. One of the causes for the unrealism of the estimated covariance is found in the classical OD approaches, as they fail to consider, or properly characterize, the uncertainty of the dynamical models used to describe the motion of the objects, such as the atmospheric drag force or the solar radiation pressure acting on the orbiting RSOs. Because these models provide a deterministic solution to a stochastic phenomenon, an inherent associated uncertainty should be regarded when used during an orbit determination. The aim of this work is to devise a methodology to improve the covariance realism of common OD processes through the classical theory of consider parameters of batch least squares methods. The methodology uses the classical theory of consider parameter to add to the estimated covariance the contribution coming from the uncertainty of the consider parameters. To do so, the variances of the consider parameters are estimated through another least squares process, with which the propagated covariance best fits a so-called observed covariance, previously derived, in a process named covariance determination. The influence of the main sources of dynamic model uncertainty can be evaluated by examining the resulting covariance correction for each uncertainty source (e.g. atmospheric drag force modelling, sensor calibration parameters or solar radiation prediction). This publication focus on studying the effect of the atmospheric drag force and range bias modelling uncertainty in the correction of an estimated covariance. The proposed methodology has been applied to a simulated realistic scenario of measurements and objects to evaluate the consistency of the corrected covariance via Monte Carlo analysis. Thorough analyses are presented to illustrate the effect of dynamic model errors on covariance realism. Copyright © 2019 by the International Astronautical Federation (IAF). All rights reserved

Towards covariance realism in batch least-squares orbit determination

Regular products within the field of Space Surveillance and Tracking (SST) and Space Traffic Management (STM), such as high-risk collisions, upcoming re-entries or fragmentations, rely both on the estimated state and associated uncertainty of detectable resident space objects (RSOs). Classical orbit determination (OD) algorithms provide the required estimations, assuming that the uncertainty in the state of the object is properly characterized by its state vector covariance and assuming Gaussian processes. However, a common problem of classical orbit determination processes is the misrepresentation of the RSOs uncertainty through the estimated covariance. Ultimately, this causes a great impact in the quality and accuracy of SST products as the estimated covariance is overly optimistic (too small) and the true uncertainty of the object is not captured. One of the causes for the unrealism of the estimated covariance is found in the classical OD approaches, as they fail to consider, or properly characterize, the uncertainty of the dynamical models used to describe the motion of the objects, such as the atmospheric drag force or the solar radiation pressure acting on the orbiting RSOs. Because these models provide a deterministic solution to a stochastic phenomenon, an inherent associated uncertainty should be regarded when used during an orbit determination. The aim of this work is to devise a methodology to improve the covariance realism of common OD processes through the classical theory of consider parameters of batch least squares methods. The methodology uses the classical theory of consider parameter to add to the estimated covariance the contribution coming from the uncertainty of the consider parameters. To do so, the variances of the consider parameters are estimated through another least squares process, with which the propagated covariance best fits a so-called observed covariance, previously derived, in a process named covariance determination. The influence of the main sources of dynamic model uncertainty can be evaluated by examining the resulting covariance correction for each uncertainty source (e.g. atmospheric drag force modelling, sensor calibration parameters or solar radiation prediction). This publication focus on studying the effect of the atmospheric drag force and range bias modelling uncertainty in the correction of an estimated covariance. The proposed methodology has been applied to a simulated realistic scenario of measurements and objects to evaluate the consistency of the corrected covariance via Monte Carlo analysis. Thorough analyses are presented to illustrate the effect of dynamic model errors on covariance realism. Copyright © 2019 by the International Astronautical Federation (IAF). All rights reserved.Astrodynamics & Space Mission