Mortality and pulmonary complications in patients undergoing surgery with perioperative SARS-CoV-2 infection: an international cohort study

Background: The impact of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) on postoperative recovery needs to be understood to inform clinical decision making during and after the COVID-19 pandemic. This study reports 30-day mortality and pulmonary complication rates in patients with perioperative SARS-CoV-2 infection. Methods: This international, multicentre, cohort study at 235 hospitals in 24 countries included all patients undergoing surgery who had SARS-CoV-2 infection confirmed within 7 days before or 30 days after surgery. The primary outcome measure was 30-day postoperative mortality and was assessed in all enrolled patients. The main secondary outcome measure was pulmonary complications, defined as pneumonia, acute respiratory distress syndrome, or unexpected postoperative ventilation. Findings: This analysis includes 1128 patients who had surgery between Jan 1 and March 31, 2020, of whom 835 (74·0%) had emergency surgery and 280 (24·8%) had elective surgery. SARS-CoV-2 infection was confirmed preoperatively in 294 (26·1%) patients. 30-day mortality was 23·8% (268 of 1128). Pulmonary complications occurred in 577 (51·2%) of 1128 patients; 30-day mortality in these patients was 38·0% (219 of 577), accounting for 81·7% (219 of 268) of all deaths. In adjusted analyses, 30-day mortality was associated with male sex (odds ratio 1·75 [95% CI 1·28–2·40], p\textless0·0001), age 70 years or older versus younger than 70 years (2·30 [1·65–3·22], p\textless0·0001), American Society of Anesthesiologists grades 3–5 versus grades 1–2 (2·35 [1·57–3·53], p\textless0·0001), malignant versus benign or obstetric diagnosis (1·55 [1·01–2·39], p=0·046), emergency versus elective surgery (1·67 [1·06–2·63], p=0·026), and major versus minor surgery (1·52 [1·01–2·31], p=0·047). Interpretation: Postoperative pulmonary complications occur in half of patients with perioperative SARS-CoV-2 infection and are associated with high mortality. Thresholds for surgery during the COVID-19 pandemic should be higher than during normal practice, particularly in men aged 70 years and older. Consideration should be given for postponing non-urgent procedures and promoting non-operative treatment to delay or avoid the need for surgery. Funding: National Institute for Health Research (NIHR), Association of Coloproctology of Great Britain and Ireland, Bowel and Cancer Research, Bowel Disease Research Foundation, Association of Upper Gastrointestinal Surgeons, British Association of Surgical Oncology, British Gynaecological Cancer Society, European Society of Coloproctology, NIHR Academy, Sarcoma UK, Vascular Society for Great Britain and Ireland, and Yorkshire Cancer Research

Polarization effects in neutron-helium scattering and the D(d, n) reaction at 50 MeV

Includes bibliographical references (leaves 130-133

Effects of Gain Changes on RPM Performance

The mission of the U.S. Department of Energy/National Nuclear Security Administration's (DOE/NNSA's) Office of the Second Line of Defense (SLD) is to strengthen the capability of foreign governments to deter, detect, and interdict the illicit trafficking of special nuclear and other radioactive materials across international borders and through the global maritime shipping system. The goal of this mission is to reduce the probability of these materials being fashioned into a weapon of mass destruction or radiological dispersal device that could be used against the United States or its international partners. This goal is achieved primarily through the installation and operation of radiation detection equipment at border crossings, airports, seaports, and other strategic locations around the world. In order to effectively detect the movement of radioactive material, the response of these radiation detectors to various materials in various configurations must be well characterized. Oak Ridge National Laboratory (ORNL) investigated two aspects of Radiation Portal Monitor (RPM) settings, based on a preliminary investigation done by the Los Alamos National Laboratory (LANL): source-to-detector distance effect on amplifier gain and optimized discriminator settings. This report discusses this investigation. A number of conclusions can be drawn from the ORNL testing. First, for increased distance between the source and the detector, thus illuminating the entire detector rather than just the center of the detector (as is done during detector alignments), an increase in gain may provide a 5-15% increase in sensitivity (Fig. 4). However, increasing the gain without adjusting the discriminator settings is not recommended as this makes the monitor more sensitive to electronic noise and temperature-induced fluctuations. Furthermore, if the discriminators are adjusted in relation to the increase in gain, thus appropriately discriminating against electronic noise, the sensitivity gains are less than 5% (Fig. 6). ORNL does not consider this slight increase in sensitivity to be a worthwhile pursuit. Second, increasing the ULD will increase sensitivity a few percent (Fig. 7); however, it is not clear that the slight increase in sensitivity is worth the effort required to make the change (e.g., reliability, cost, etc.). Additionally, while the monitor would be more sensitive to HEU, it would also be more sensitive to NORM. Third, the sensitivity of the system remains approximately the same whether it is calibrated to a small source on contact or a large source far away (Fig. 6). This affirms that no changes to the existing calibration procedure are necessary

Effects of Gain Changes on RPM Performance

The mission of the U.S. Department of Energy/National Nuclear Security Administration's (DOE/NNSA's) Office of the Second Line of Defense (SLD) is to strengthen the capability of foreign governments to deter, detect, and interdict the illicit trafficking of special nuclear and other radioactive materials across international borders and through the global maritime shipping system. The goal of this mission is to reduce the probability of these materials being fashioned into a weapon of mass destruction or radiological dispersal device that could be used against the United States or its international partners. This goal is achieved primarily through the installation and operation of radiation detection equipment at border crossings, airports, seaports, and other strategic locations around the world. In order to effectively detect the movement of radioactive material, the response of these radiation detectors to various materials in various configurations must be well characterized. Oak Ridge National Laboratory (ORNL) investigated two aspects of Radiation Portal Monitor (RPM) settings, based on a preliminary investigation done by the Los Alamos National Laboratory (LANL): source-to-detector distance effect on amplifier gain and optimized discriminator settings. This report discusses this investigation. A number of conclusions can be drawn from the ORNL testing. First, for increased distance between the source and the detector, thus illuminating the entire detector rather than just the center of the detector (as is done during detector alignments), an increase in gain may provide a 5-15% increase in sensitivity (Fig. 4). However, increasing the gain without adjusting the discriminator settings is not recommended as this makes the monitor more sensitive to electronic noise and temperature-induced fluctuations. Furthermore, if the discriminators are adjusted in relation to the increase in gain, thus appropriately discriminating against electronic noise, the sensitivity gains are less than 5% (Fig. 6). ORNL does not consider this slight increase in sensitivity to be a worthwhile pursuit. Second, increasing the ULD will increase sensitivity a few percent (Fig. 7); however, it is not clear that the slight increase in sensitivity is worth the effort required to make the change (e.g., reliability, cost, etc.). Additionally, while the monitor would be more sensitive to HEU, it would also be more sensitive to NORM. Third, the sensitivity of the system remains approximately the same whether it is calibrated to a small source on contact or a large source far away (Fig. 6). This affirms that no changes to the existing calibration procedure are necessary

May 2017 Meeting

Notes from the May Meetin