The assessment of patients undergoing cardiac surgery for Covid-19: Complications occurring during cardiopulmonary bypass.

The outbreak of the novel coronavirus pandemic (COVID-19) has resulted in dramatic changes to the conduct of surgery both from a patient management perspective and in protecting healthcare providers. The current study reports on the status of COVID-19 infections in patients presenting for cardiac surgery with cardiopulmonary bypass (CPB) on circuit complications. A tracking process for monitoring the presence of COVID-19 in adult cardiac surgery patients was integrated into a case documentation system across United States hospitals where out-sourced perfusion services were provided. Assessment included infection status, testing technique employed, surgery status and CPB complications. Records from 5612 adult patients who underwent cardiac surgery between November 1, 2020 and January 18, 2021 from 176 hospitals were reviewed. A sub-cohort of coronary artery bypass graft patients (3283) was compared using a mixed effect binary logistic regression analysis. 4297 patients had negative test results (76.6%) while 49 (0.9%) tested positive for COVID-19, and unknown or no results were reported in 693 (12.4%) and 573 (10.2%) respectively. Coagulation complications were reported at 0.2% in the negative test results group versus 4.1% in the positive test result group (p < 0.001). Oxygenator gas exchange complications were 0.2% in the negative test results group versus 2.0% in the positive test results group (p = 0.088). Coronary artery bypass graft patients with a positive test had significantly higher risk for any CPB complication (p = 0.003) [OR 10.38, CI 2.18-49.53] then negative test patients [OR 0.01, CI 0.00-0.20]. The present study has shown that patients undergoing cardiac surgery with CPB who test positive for COVID-19 have higher CPB complication rate than those who test negative.

Combining Heparin and a FX/Xa Aptamer to Reduce Thrombin Generation in Cardiopulmonary Bypass and COVID-19.

Known limitations of unfractionated heparin (UFH) have encouraged the evaluation of anticoagulant aptamers as alternatives to UFH in highly procoagulant settings such as cardiopulmonary bypass (CPB). Despite progress, these efforts have not been totally successful. We take a different approach and explore whether properties of an anticoagulant aptamer can complement UFH, rather than replace it, to address shortcomings with UFH use. Combining RNA aptamer 11F7t, which targets factor X/Xa, with UFH (or low molecular weight heparin) yields a significantly enhanced anticoagulant cocktail effective in normal and COVID-19 patient blood. This aptamer-UFH combination (1) supports continuous circulation of human blood through an ex vivo membrane oxygenation circuit, as is required for patients undergoing CPB and COVID-19 patients requiring extracorporeal membrane oxygenation, (2) allows for a reduced level of UFH to be employed, (3) more effectively limits thrombin generation compared to UFH alone, and (4) is rapidly reversed by the administration of protamine sulfate, the standard treatment for reversing UFH clinically following CPB. Thus, the combination of factor X/Xa aptamer and UFH has significantly improved anticoagulant properties compared to UFH alone and underscores the potential of RNA aptamers to improve medical management of acute care patients requiring potent yet rapidly reversible anticoagulation.

Bleeding Complications in Patients With Perioperative COVID-19 Infection Undergoing Cardiac Surgery: A Single-Center Matched Case-Control Study.

OBJECTIVE: Previous studies reported a poor outcome in patients with coronavirus 2019 (COVID-19) undergoing cardiac surgery. Complications most frequently described were respiratory failure, renal failure, and thromboembolic events. In their recent experience, the authors observed a very high incidence of bleeding complications. The purpose of the study was to investigate a possible significant correlation between perioperative COVID-19 infection and hemorrhagic complications compared to non-COVID-19 patients. DESIGN: Single-center, observational, retrospective, matched case-control (1:2) study involving patients who underwent open-heart cardiac surgery from February 2020 and March 2021 with positive perioperative diagnosis of COVID-19 infection, matched with patients without COVID-19 infection. SETTING: Cardiac surgery unit and intensive care unit of a university tertiary center in a metropolitan area. PARTICIPANTS: In the study period, 773 patients underwent cardiac surgery on cardiopulmonary bypass (CPB). Among them, 23 consecutive patients had perioperative diagnosis of COVID-19 infection (study group). These patients were compared with 46 corresponding controls (control group) that matched for age, sex, body mass index, and Society of Thoracic Surgeons score. INTERVENTIONS: Open-heart cardiac surgery on CPB. MEASUREMENTS AND MAIN RESULTS: In the study group, 2 patients (9%) died in the intensive care unit from severe respiratory failure, shock, and multiple organ failure. In the study group, patients showed a significantly higher incidence of bleeding complications (48% v 2%, p = 0.0001) and cases of surgical reexploration for bleeding (35% v 2%, p = 0.0001), a higher incidence of severe postoperative thrombocytopenia (39% v 6%, p = 0.0007), and a higher need of blood components transfusions (74% v 30%, p = 0.0006). Chest tubes blood loss and surgical hemostasis time were markedly prolonged (p = 0.02 and p = 0.003, respectively). CONCLUSIONS: A worrisome increased risk of early and late bleeding complications in COVID-19 patients was observed, and it should be considered when assessing the operative risk. CPB-related inflammatory reaction could exacerbate the deleterious effect of COVID-19 on the coagulation system and likely deviate it toward a hemorrhagic pattern.

Prophylactic corticosteroids for paediatric heart surgery with cardiopulmonary bypass.

BACKGROUND: Corticosteroids are routinely given to children undergoing cardiac surgery with cardiopulmonary bypass (CPB) in an attempt to ameliorate the inflammatory response. Their use is still controversial and the decision to administer the intervention can vary by centre and/or by individual doctors within that centre. OBJECTIVES: This review is designed to assess the benefits and harms of prophylactic corticosteroids in children between birth and 18 years of age undergoing cardiac surgery with CPB. SEARCH METHODS: We searched CENTRAL, MEDLINE, Embase and Conference Proceedings Citation Index-Science in June 2020. We also searched four clinical trials registers and conducted backward and forward citation searching of relevant articles. SELECTION CRITERIA: We included studies of prophylactic administration of corticosteroids, including single and multiple doses, and all types of corticosteroids administered via any route and at any time-point in the perioperative period. We excluded studies if steroids were administered therapeutically. We included individually randomised controlled trials (RCTs), with two or more groups (e.g. multi-drug or dose comparisons with a control group) but not 'head-to-head' trials without a placebo or a group that did not receive corticosteroids. We included studies in children, from birth up to 18 years of age, including preterm infants, undergoing cardiac surgery with the use of CPB. We also excluded studies in patients undergoing heart or lung transplantation, or both; studies in patients already receiving corticosteroids; in patients with abnormalities of the hypothalamic-pituitary-adrenal axis; and in patients given steroids at the time of cardiac surgery for indications other than cardiac surgery. DATA COLLECTION AND ANALYSIS: We used the Covidence systematic review manager to extract and manage data for the review. Two review authors independently assessed studies for inclusion, extracted data, and assessed risks of bias. We resolved disagreements by consensus or by consultation with a third review author. We assessed the certainty of evidence with GRADE. MAIN RESULTS: We found 3748 studies, of which 888 were duplicate records. Two studies had the same clinical trial registration number, but reported different populations and interventions. We therefore included them as separate studies. We screened titles and abstracts of 2868 records and reviewed full text reports for 84 studies to determine eligibility. We extracted data for 13 studies. Pooled analyses are based on eight studies. We reported the remaining five studies narratively due to zero events for both intervention and placebo in the outcomes of interest. Therefore, the final meta-analysis included eight studies with a combined population of 478 participants. There was a low or unclear risk of bias across the domains. There was moderate certainty of evidence that corticosteroids do not change the risk of in-hospital mortality (five RCTs; 313 participants; risk ratio (RR) 0.83, 95% confidence interval (CI) 0.33 to 2.07) for children undergoing cardiac surgery with CPB. There was high certainty of evidence that corticosteroids reduce the duration of mechanical ventilation (six RCTs; 421 participants; mean difference (MD) 11.37 hours lower, 95% CI -20.29 to -2.45) after the surgery. There was high-certainty evidence that the intervention probably made little to no difference to the length of postoperative intensive care unit (ICU) stay (six RCTs; 421 participants; MD 0.28 days lower, 95% CI -0.79 to 0.24) and moderate-certainty evidence that the intervention probably made little to no difference to the length of the postoperative hospital stay (one RCT; 176 participants; mean length of stay 22 days; MD -0.70 days, 95% CI -2.62 to 1.22). There was moderate certainty of evidence for no effect of the intervention on all-cause mortality at the longest follow-up (five RCTs; 313 participants; RR 0.83, 95% CI 0.33 to 2.07) or cardiovascular mortality at the longest follow-up (three RCTs; 109 participants; RR 0.40, 95% CI 0.07 to 2.46). There was low certainty of evidence that corticosteroids probably make little to no difference to children separating from CPB (one RCT; 40 participants; RR 0.20, 95% CI 0.01 to 3.92). We were unable to report information regarding adverse events of the intervention due to the heterogeneity of reporting of outcomes. We downgraded the certainty of evidence for several reasons, including imprecision due to small sample sizes, a single study providing data for an individual outcome, the inclusion of both appreciable benefit and harm in the confidence interval, and publication bias. AUTHORS' CONCLUSIONS: Corticosteroids  probably do not change the risk of mortality for children having heart surgery using CPB at any time point. They probably reduce the duration of postoperative ventilation in this context, but have little or no effect on the total length of postoperative ICU stay or total postoperative hospital stay. There was inconsistency in the adverse event outcomes reported which, consequently, could not be pooled. It is therefore impossible to provide any implications and policy-makers will be unable to make any recommendations for practice without evidence about adverse effects. The review highlighted the need for well-conducted RCTs powered for clinical outcomes to confirm or refute the effect of corticosteroids versus placebo in children having cardiac surgery with CPB. A core outcome set for adverse event reporting in the paediatric major surgery and intensive care setting is required.