G. Guyatt’s research while affiliated with McMaster University and other places

Purpose This multicenter Canadian prospective cohort study evaluated the accuracy of physician predictions in comparison to model predictions in estimating 1-year mortality in ambulatory patients with heart failure (HF). Methods We included consented consecutive ambulatory HF patients (left ventricular ejection fraction (LVEF) <40%) followed at 11 HF clinics in 5 provinces in Canada (2018-2020). In a closed-question survey, HF cardiologists and family doctors, using their clinical judgment, estimated patient 1-year mortality in absolute terms. We collected clinical information to describe the population and calculate predicted mortality using three predictive models: the Seattle HF Model (SHFM), the MAGGIC score and the HF Meta-score. We documented patients’ mortality over one year. Physicians were unaware of model predictions. We calculated mortality using Cox proportional hazards and assessed model and physician predictive accuracy using discrimination and calibration. Results We included 1,563 ambulatory HF patients, mean age of 63±14 years, 24% female, 70% NTHA class I-II, mean LVEF of 28±7%, and median brain natriuretic peptide of 350 pg/ml (25th-75th percentile 130-700). The population 1-year mortality was 7% (95%CI 6%-8%). Models’ discrimination (c-statistic 0.80 for MAGGIC and HF meta-score, 0.84 for SHFM) proved superior to physicians (0.77 for family doctors and 0.78 for HF cardiologists). Models’ calibration was adequate for patients at lower risk, but overestimated risk in those whose 1-year mortality was > 20%. In contrast, family doctors and HF cardiologists overestimated risk throughout the risk spectrum. In low-risk patients (1-year mortality ∼1%), physicians predicted a risk 7%-10%; in medium-risk patients (1-year mortality ∼5%), physicians predicted 15%-20%; and in high-risk patients (mortality >15%), physicians predicted >25%. Conclusion Predictive models showed higher accuracy in predicting 1-year mortality in ambulatory HF population than family doctors and HF cardiologists, both of whom consistently overestimated risk, potentially exposing patients early to more aggressive care. Incorporating predictive models in family and HF cardiology practices may improve patient management and resource use.

Purpose Early graft dysfunction (EGD) is a major cause of morbidity and mortality following heart transplantation (HT). Severe EGD often includes the use of veno-arterial extracorporeal membrane oxygenation (VA-ECMO). Studies evaluating its effectiveness are mostly single centre observations with variable outcomes. This systematic review and meta-analysis appraises the available evidence and evaluates prognosis in HT patients with EGD requiring VA-ECMO. Methods We conducted a systematic search of Ovid Medline, Embase and the Cochrane databases to 05/15/2020. Studies of adults who received VA-ECMO during their index hospitalization after HT and reported on mortality at any timepoint were included. We included observational studies published after 2009, in any language, as abstracts or full texts. Outcomes of interest were short-term mortality, 1-year mortality and VA-ECMO complications. We used QUIPS to assess risk of bias and GRADE to assess the quality of the evidence. Data was pooled using random-effects models. Results We included 50 studies of 1472 patients with 504 short-term mortality events. Most studies were retrospective (94%), single centre (88%), and at low/acceptable risk of bias overall (76%). Pooled short-term mortality was 33% (95%CI: 27-38%, I² =76%) and 1-year mortality was 46% (95%CI: 37-54%, I² =81%). Risk of bias, publication type, recruitment timeframe, and use of VA-ECMO for only primary graft dysfunction as per the ISHLT definition did not explain heterogeneity in subgroup analyses. Reported VA-ECMO complications were 38% (95%CI: 27-49%) for dialysis, 36% (95%CI: 26-47%) for bleeding, 22% (95%CI: 14-31%) for infection and 5% (95%CI: 1-10%) for limb ischemia. Conclusion One-third of HT patients with EGD supported with VA-ECMO are at risk of short-term death. An individual patient data meta-analysis is warranted to further understand the mortality risk and gain insight into risk factors associated with outcomes in this population.

Introduction: eCTAS is a real time electronic triage decision-support tool designed to improve patient safety and quality of care by standardizing the application of the Canadian Triage and Acuity Scale (CTAS). The tool dynamically calculates a recommended CTAS score based on the presenting complaint, vital signs and selected clinical modifiers. The primary objective was to assess consistency of CTAS score distributions across 35 emergency departments (EDs) by 16 presenting complaints pre and post eCTAS implementation. Methods: This retrospective cohort study used population-based administrative data from January 2016 to December 2018 from all hospital EDs in Ontario that had implemented eCTAS with at least 9 months of data. Following a 3-month stabilization period, we compared data for 6 months post-eCTAS implementation to the same 6-month period the previous year (pre-implementation) to account for potential seasonal variation, patient volume and case-mix. We included triage encounters of adult (≥18 years) patients if they had one of 16 pre-specified high-volume, presenting complaints. A paired-samples t-test was used to determine consistency by estimating the absolute difference in CTAS distribution for each presenting complaint, by each hospital, pre and post eCTAS implementation, compared to the overall average of the 35 EDs. Results: There were 183,231 triage encounters in the pre-eCTAS cohort and 179,983 in the post-eCTAS cohort from 35 EDs across the province. Triage scores were more consistent with the overall average after eCTAS implementation in 6 (37.5%) presenting complaints: chest pain (cardiac features) (p < 0.001), extremity weakness/symptoms of cerebrovascular accident (p < 0.001), fever (p < 0.001), shortness of breath (p < 0.001), syncope (p = 0.02), and hyperglycemia (p = 0.03). Triage consistency was similar pre and post eCTAS implementation for the presenting complaints of altered level of consciousness, anxiety/situational crisis, confusion, depression/suicidal/deliberate self-harm, general weakness, head injury, palpitations, seizure, substance misuse/intoxication or vertigo. Conclusion: A standardized, electronic approach to performing triage assessments increased consistency in CTAS scores across many, but not all, high-volume CEDIS complaints. This does not reflect triage accuracy, as there are no known benchmarks for triage accuracy. Improvements in consistency were greatest for sentinel presenting complaints with a minimum allowable CTAS score.