Off-Pump Coronary Artery Surgery for Reducing Mortality and Morbidity Meta-Analysis of Randomized and Observational Studies

ObjectivesThe purpose of this study was to assess the effects of off-pump coronary bypass surgery (OPCAB) on mortality and morbidity.BackgroundDespite its potential for reducing morbidity and mortality, OPCAB’s role in clinical practice remains controversial.MethodsA meta-analysis of 37 randomized controlled trials (RCTs) (n=3,449) and 22 risk-adjusted (logistic regression or propensity-score) observational studies (n=293,617) was performed. Two reviewers performed literature searches (MEDLINE, EMBASE, PubMed, reference lists), quality assessment, and data extraction. Treatment effects were calculated as odds ratios (ORs) with 95% confidence intervals (CIs).ResultsIn RCTs, OPCAB was associated with reduced atrial fibrillation (OR 0.59; 95% CI 0.46 to 0.77) and trends toward reduced 30-day mortality (OR 0.91 95% CI 0.45 to 1.83), stroke (OR 0.52; 95% CI 0.25 to 1.05), and myocardial infarction (OR 0.79; 95% CI 0.50 to 1.25). Observational studies showed OPCAB to be associated with reduced 30-day mortality (OR 0.72; 95% CI 0.66 to 0.78), stroke (OR 0.62; 95% CI 0.55 to 0.69), infarction (OR 0.66; 95% CI 0.50 to 0.88), and atrial fibrillation (OR 0.78; 95% CI 0.74 to 0.82). At one to two years, OPCAB was associated with trends toward reduced mortality, but also increased repeat revascularization (RCT: OR 1.75, 95% CI 0.78 to 3.94; Observational: OR 1.35, 95% CI 0.76 to 2.39).ConclusionsRandomized controlled trials did not find, aside from atrial fibrillation, the statistically significant reductions in short-term mortality and morbidity demonstrated by observational studies. These discrepancies might be due to differing patient-selection and study methodology. Future studies must focus on improving research methodology, recruiting high-risk patients, and collecting long-term data

Biomarkers of coagulation, endothelial function, and fibrinolysis in critically ill patients with COVID-19: A single-center prospective longitudinal study

Background: Immunothrombosis and coagulopathy in the lung microvasculature may lead to lung injury and disease progression in coronavirus disease 2019 (COVID-19). We aim to identify biomarkers of coagulation, endothelial function, and fibrinolysis that are associated with disease severity and may have prognostic potential. Methods: We performed a single-center prospective study of 14 adult COVID-19(+) intensive care unit patients who were age- and sex-matched to 14 COVID-19(−) intensive care unit patients, and healthy controls. Daily blood draws, clinical data, and patient characteristics were collected. Baseline values for 10 biomarkers of interest were compared between the three groups, and visualized using Fisher\u27s linear discriminant function. Linear repeated-measures mixed models were used to screen biomarkers for associations with mortality. Selected biomarkers were further explored and entered into an unsupervised longitudinal clustering machine learning algorithm to identify trends and targets that may be used for future predictive modelling efforts. Results: Elevated D-dimer was the strongest contributor in distinguishing COVID-19 status; however, D-dimer was not associated with survival. Variable selection identified clot lysis time, and antigen levels of soluble thrombomodulin (sTM), plasminogen activator inhibitor-1 (PAI-1), and plasminogen as biomarkers associated with death. Longitudinal multivariate k-means clustering on these biomarkers alone identified two clusters of COVID-19(+) patients: low (30%) and high (100%) mortality groups. Biomarker trajectories that characterized the high mortality cluster were higher clot lysis times (inhibited fibrinolysis), higher sTM and PAI-1 levels, and lower plasminogen levels. Conclusions: Longitudinal trajectories of clot lysis time, sTM, PAI-1, and plasminogen may have predictive ability for mortality in COVID-19

Should all patients having elective first-time coronary bypass grafting surgery be crossmatched for blood?

grantor: University of TorontoCurrently blood is reserved (crossmatched) for all patients having coronary artery bypass grafting (CABG) surgery. Many patients, however, will not require any blood and are therefore unnecessarily crossmatched. This practice reduces the general pool of blood in blood banks, increases costs, and leads to wastage of blood. In this study, a clinical prediction rule was developed on 737 patients having elective first- time CABG surgery that allows physicians to predict which patients will need blood during surgery, and only crossmatch blood for these patients. The rule includes four commonly available preoperative patient variables: preoperative haemoglobin, weight, age, and sex. The rule, which was validated on another 296 patients, is accurate (sensitivity = 87.4%, specificity = 57.8%), and should perform well on other patient populations. Application of this rule will eliminate crossmatching in about 50% of patients having elective first-time CABG surgery.M.Sc

Which is the preferred blood product for fibrinogen replacement in the bleeding patient with acquired hypofibrinogenemia-cryoprecipitate or fibrinogen concentrate?

The importance of the targeted treatment of acquired hypofibrinogenemia during hemorrhage with a concentrated fibrinogen product (either cryoprecipitate or fibrinogen concentrate) cannot be underestimated. Fibrinogen concentrate is a pathogen inactivated, pooled product that offers a highly purified single factor concentrate. Cryoprecipitate is a pooled product that comes with a spectrum of other coagulation factors which may further enhance (additional procoagulant effect) or even disturb (prothrombotic risk) hemostasis. The pros and cons of each product are discussed

Fibrinogen Supplementation and Its Indications

Adequate plasma levels of fibrinogen are essential for clot formation, and in severe bleeding, fibrinogen reaches a critically low plasma concentration earlier than other coagulation factors. Although the critical minimum concentration of fibrinogen to maintain hemostasis is a matter of debate, many patients with coagulopathic bleeding require fibrinogen supplementation. Among the treatment options for fibrinogen supplementation, fibrinogen concentrate may be viewed by some as preferable to fresh frozen plasma or cryoprecipitate. The authors review major studies that have assessed fibrinogen treatment in trauma, cardiac surgery, end-stage liver disease, postpartum hemorrhage, and pediatric patients. Some but not all randomized controlled trials have shown that fibrinogen concentrate can be beneficial in these settings. The use of fibrinogen as part of coagulation factor concentrate based therapy guided by point-of-care viscoelastic coagulation monitoring (ROTEM [rotational thromboelastometry] or TEG [thromboelastography]) appears promising. In addition to reducing patients' exposure to allogeneic blood products, this strategy may reduce the risk of complications such as transfusion-associated circulatory overload, transfusion-related acute lung injury, and thromboembolic adverse events. Randomized controlled trials are challenging to perform in patients with critical bleeding, and more evidence is needed in this setting. However, current scientific rationale and clinical data support fibrinogen repletion in patients with ongoing bleeding and confirmed fibrinogen deficiency