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

POPULATION DYNAMICS OF SUGAR MAPLE (ACER SACCHARUM MARSH.) AT THE SOUTHERN PORTION OF ITS RANGE: IMPLICATIONS FOR RANGE MIGRATION AND SUCCESSION by CRAIG TURBERVILLE

ABSTRACT Evidence for climate change driven range migration exists for a variety of tree species in eastern North America. Northward range migration for tree species in the region requires a decrease in population density near the southern range boundary coupled with an increase in population density at the northern range boundary. Sugar maple (Acer saccharum Marsh.) is one such species that has been projected by some biogeographic models to shift north in accord with climate. However, a widespread pattern of increased sugar maple density has been reported in the forest science literature from a variety of sites throughout the species' range. This pattern is linked to a complex of interacting factors and has been hypothesized to represent a positive feedback that facilitates sugar maple regeneration. The primary goal of my study was to test which of these hypotheses (range migration or succession) was correct for the southern portion of the sugar maple range. I used Forest Inventory and Analysis program data to compare regionwide population dynamics for this species on a plot-by-plot basis. Changes in frequency, density, and dominance of sugar maple trees and seedlings were compared over multiple years for the states of Alabama, Kentucky, North Carolina, Tennessee, Virginia, and West Virginia. Plot data for all states were combined to determine changes in frequency, density, and dominance for the contiguous and non-contiguous regions of sugar maple's southern range portion. Results indicated increases in frequency, density, and dominance of sugar maple within its contiguous range coupled with decreases outside of the contiguous range. It is postulated based on these data that sugar maple's southern range boundary will remain stabilized while the northern boundary will continue to migrate with increasing global temperatures. iii ACKNOWLEDGEMENT