Mississauga Hospital is a regional and teaching hospital in Mississauga, Ontario, Canada. It provides general medical services to residents of central and southern Mississauga as well as regional stroke, cardiac, and neurological care.Founded in 1958 as South Peel Hospital, the hospital was renamed to Mississauga Hospital in 1980. After a 1997 government mandate to restructure, the hospital merged with the nearby Queensway General Hospital in Toronto in April 1998 to form a new hospital corporation named Trillium Health Centre. From 1998 to 2011 the hospital was known as Trillium Health Centre Mississauga. The name was reverted to Mississauga Hospital following Trillium Health Centre's merger with Credit Valley Hospital on December 1, 2011 to form Trillium Health Partners.In 2022, Trillium received a $105 million donation from the Peter Gilgan Foundation, for this hospital and Queensway Health Centre. After the rebuild of the hospital, it will be known as the Peter Gilgan Mississauga Hospital.
Background: SARS-COV2 infection has been linked to cardiovascular complications. Published data suggest that cardiac injury may be a common disease feature and contribute to morbidity and mortality in severe COVID-19. Since early in the pandemic, little data has emerged describing what cardiovascular complications arise from myocardial injury in severe COVID-19 and whether these complications contribute to mortality. Objectives: Describe the incidence and nature of cardiovascular complications in patients with severe COVID-19 infection and biochemical or imaging evidence of myocardial injury. Methods: We analyzed consecutive patients admitted for severe COVID-19 and presenting with biochemical or echocardiographic evidence of myocardial injury across 16 centers within the CARDIO-COVID investigator-initiated consortium. A light-GBM machine learning model was used to identify variables associated with mortality. Results: Our study included 1,328 patients. ICU mortality was 29.4%. Factors most associated with mortality were age, SOFA Cardiovascular score, elevated troponin, intubation, high vasoactive-inotropic score (VIS), high PEEP, and high FiO2. Individual cardiovascular (myocardial infarction, stroke, pulmonary embolism, myocarditis, VT/VF, new onset heart failure) complications were rare (all <5%) but common in sum (17.6%), and did not present significant association with mortality. Patients with high VIS and SOFA Cardiovascular scores had a significantly higher incidence of secondary bacterial pneumonias suggesting septic shock played a role in their physiology. Investigator-adjudicated cause of death data identified respiratory failure and septic shock as primary causes of mortality. Conclusions: Though cardiovascular complications of severe COVID-19 are common, they do not seem to contribute significantly to mortality. Elevated cardiac enzymes and myocardial dysfunction carry prognostic value likely reflecting myocardial strain in the setting of multisystem organ dysfunction rather than direct myocardial injury by SARS-CoV2.
BACKGROUND:Spirometry is the standard physiological test defining airflow obstruction, the key criterion for diagnosing chronic obstructive pulmonary disease. It is underused in high-income settings and often unavailable in low- and middle-income countries, causing underdetection. Deep learning analysis of chest radiographs, which are widely available where spirometry is not, may complement spirometric screening, but its use in North American cohorts and across demographic strata has not been examined. OBJECTIVE:This study aimed to train a deep learning model to estimate the forced expiratory volume in 1 second (FEV₁)/forced vital capacity (FVC) ratio from chest radiographs and classify airflow obstruction (FEV₁/FVC <0.70), evaluate it on a held-out test set, and audit subgroup performance across age, sex, and surname-inferred ethnicity. METHODS:We conducted a retrospective cohort study of 3537 adults who underwent prebronchodilator spirometry and chest radiography within 30 days at a large hospital network in Ontario, Canada, between October 2020 and May 2023. A ConvNeXt-Base architecture pretrained on ImageNet was trained to predict FEV₁/FVC, with predictions classified using a 0.70 cutoff for binary airflow limitation. At the patient level, the cohort was divided into training (n=2263), validation (n=566), and held-out test (n=708 patients; 3273 examinations) sets. Performance was assessed using regression (mean absolute error [MAE], root mean squared error [RMSE], and Pearson r), classification (sensitivity, specificity, positive and negative predictive value [PPV and NPV], and likelihood ratios [LR+ and LR-]), calibration, and decision curve metrics, with 95% CIs from patient-level cluster bootstrap (1000 resamples). Subgroup analyses used Holm correction and two 1-sided tests. RESULTS:In the held-out test cohort, MAE was 0.08 (95% CI 0.07-0.09) and RMSE was 0.10 (95% CI 0.10-0.11). For binary obstruction, sensitivity was 0.70 (95% CI 0.65-0.74), specificity 0.72 (95% CI 0.67-0.76), PPV 0.71 (95% CI 0.65-0.76), NPV 0.71 (95% CI 0.66-0.76), LR+ 2.46 (95% CI 2.11-2.88), and LR- 0.42 (95% CI 0.36-0.49). Patient-level estimates were similar (sensitivity 0.69, 95% CI 0.66-0.72; specificity 0.74, 95% CI 0.71-0.78). Calibration was excellent for regression (slope=0.97; intercept=0.015) and mildly miscalibrated for the binary task (slope=1.41; intercept=0.04; Brier=0.195). Decision curve analysis showed net benefit at threshold probabilities of approximately 0.27 to 0.86. Sensitivity was meaningfully reduced in Asian patients (0.43, 95% CI 0.29-0.56) compared with White patients (0.75, 95% CI 0.70-0.79; absolute difference -0.32; Holm P<.001), with accompanying differences in specificity, PPV, and LR-, and was lower in younger age groups, peaking at 65-74 years. CONCLUSIONS:A deep learning model trained on routine chest radiographs estimated FEV₁/FVC and identified airflow limitation in a North American cohort, with moderate discrimination, well-calibrated regression predictions, and positive net benefit. Performance was not uniform across demographic strata, with reduced sensitivity in Asian patients and younger age groups. Multisite external validation and subgroup-specific verification are important next steps.
Clinicians presume a relationship between the management of blood pressure during cardiac surgery and postoperative morbidity and mortality. With limited evidence to inform practice, we surveyed Canadian cardiac anesthesiologists, perfusionists, and cardiac surgeons. We sought to solicit information to inform a trial evaluating the blood pressure management approach on outcomes after cardiac surgery. We iteratively developed a survey assessing the lowest and highest blood pressures respondents would target, the narrowest feasible blood pressure range to achieve, the range of blood pressure observed in clinical practice, and factors influencing targeted blood pressure before, during, and after cardiopulmonary bypass (CPB). We contacted leads from every Canadian hospital providing cardiac surgery to distribute the survey via a computerized link. We used a modified Dillman approach to optimize response rate. Responses were analyzed descriptively. Of 819 clinicians surveyed, 532 (65
Periorbital and orbital cellulitis are common infections in the paediatric population requiring interdisciplinary management. However, there are no Canadian clinical practice guidelines to evaluate and manage these severe orbital infections, and wide variation in care. To describe clinical practice patterns in admission, diagnostic tests, antibiotic therapy, subspecialty consultation, and discharge recommendations across Canadian hospitals. A cross-sectional survey of general paediatricians at children’s and community hospitals across Canada, and paediatric emergency department (ED) physicians at children’s hospitals was conducted. The survey was distributed through the Canadian Paediatric Inpatient Research Network (PIRN), and completed by one representative per hospital. Site-level clinical management specific to each provider type was assessed. Data were analyzed descriptively. Of 59 individuals contacted, 43 responded (72.9%) of which 19 (44.2%) were community hospital paediatricians, 13 (30.2%) were children’s hospitals paediatricians, and 11 (25.6%) were paediatric ED physicians. Only one hospital had a comprehensive clinical practice guideline. The most frequently ordered tests in the ED were CBC (81.9%) and CRP (81.9%). Abnormal vision and painful extra-ocular movements were indicators for admission. For admitted children, CT scans were ordered ‘always or frequently’ by 46.2% of children’s hospital paediatricians and 5.3% of community hospital paediatricians. Ophthalmology (n=11, 84.6%), otolaryngology (n=9, 69.2%), and infectious diseases (n=6, 46.2%) were frequently consulted at children’s hospitals. Patients with periorbital cellulitis who did not require admission were usually discharged home on oral cephalexin. Table 1 outlines antibiotic selections for admitted patients. There is no consensus on diagnostic test usage, subspeciality consultation, and empiric antibiotic therapy for severe orbital infections. A Canadian clinical practice guideline is needed to help standardize management.
