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Background: The increasing complexity of congenital cardiac surgery has led to greater utilization of extracorporeal membrane oxygenation (ECMO) support for children post‐surgery. This study aims to identify risk factors for mortality and brain injury in pediatric patients requiring post‐cardiotomy ECMO and to evaluate their neurological outcomes. Methods: This retrospective study includes pediatric patients with congenital heart diseases who required ECMO after surgery. Risk factors for in‐hospital mortality and brain injury were assessed. Neurodevelopmental status was determined using the Pediatric Cerebral Performance Category (PCPC) Scale at discharge and during follow‐up. Results: Between October 2014 and May 2021, 2651 pediatric patients underwent cardiac surgery, with 90 (3.4%) requiring ECMO. The mean age was 0.6 years, ranging from 1 day to 13 years and 7 months. ECMO was implemented for 45 patients due to CPB weaning failure (NW‐CPB), 24 due to postoperative low‐cardiac output syndrome (LCOS), and 21 for extracorporeal cardiopulmonary resuscitation (E‐CPR). ECMO weaning was achieved in 73 patients (81%), with an overall mortality rate of 36%. Pre‐implant lactate levels (OR: 1.13, 95% CI: 1.03–1.25; p = 0.009) and peak bilirubin levels (OR: 1.04, 95% CI: 0.87–1.24; p = 0.69) were risk factors for in‐hospital mortality. Survival rates were 79% for LCOS, 60% for NW‐CPB, and 48% for E‐CPR. Brain injury incidence was 33%, with E‐CPR being a significant risk factor (p = 0.006) and NW‐CPB being protective (p = 0.001). Follow‐up in November 2023 showed significant improvement in neurodevelopmental status (p < 0.001). Conclusion: Elevated pre‐implant lactate and elevated bilirubin levels during ECMO are major risk factors for mortality. E‐CPR is the primary risk factor for brain injury. Follow‐up revealed significant improvements in neurodevelopmental outcomes. [ABSTRACT FROM AUTHOR]

Introduction: cardiac surgery associated acute kidney injury (CSA-AKI) has a number of preoperative and intraoperative risk factors. Cardiopulmonary bypass (CPB) factors have not yet been elucidated in a single multivariate model. The aim of this study is to develop a dynamic predictive model for CSA-AKI. Methods: retrospective study on 910 consecutive adult cardiac surgery patients. Baseline data were used to settle a preoperative CSA-AKI risk model (static risk model, SRM); CPB related data were assessed for association with CSA-AKI. CPB duration, nadir oxygen delivery, time of exposure to a low oxygen delivery, nadir mean arterial pressure, peak lactates and red blood cell transfusion were included in a multivariate dynamic perfusion risk (DPR). SRM and DPR were merged into a final logistic regression model (multifactorial dynamic perfusion index, MDPI). The three risk models were assessed for discrimination and calibration. Results: the SRM model had an AUC of 0.696 (95% CI 0.663–0.727), the DPR model of 0.723 (95% CI 0.691–0.753), and the MDPI model an AUC of 0.769 (95% CI 0.739–0.798). The difference in AUC between SRM and DPR was not significant (p = 0.495) whereas the AUC of MDPI was significantly larger than that of SRM (p = 0.004) and DPR (p = 0.015). Conclusions: inclusion of dynamic indices of the quality of CPB improves the discrimination and calibration of the preoperative risk scores. The MDPI has better predictive ability than the existing static risk models and is a promising tool to integrate different factors into an advanced concept of goal-directed perfusion. [ABSTRACT FROM AUTHOR]

Cardiac surgery-associated acute kidney injury (CSA-AKI) is a relatively common feature, leading to increased morbidity and mortality. Within this setting, cardiopulmonary bypass (CPB) plays a major role. Recently, CPB-related factors (CPB duration, nadir DO2, time of exposure to a critical DO2, nadir hematocrit [HCT], nadir mean arterial pressure [MAP], red blood cell [RBC] transfusions, and arterial blood lactate) were merged together in the Multifactorial Dynamic Perfusion Index (MDPI) that showed a very good predictive power for CSA-AKI. An additional risk factor was subsequently identified (use of norepinephrine). RBC transfusions are used to correct a low HCT, and norepinephrine to correct hypotension. This study is a post-hoc analysis of the two studies proposing and validating the MDPI, with the purpose of defining the respective role of the different risk factors. This is a post-hoc analysis of the prospective observational study PErfusion QUality ODds (PEQUOD) investigating the respective role of hemodilution, hypotension, and their corrective measures (RBC transfusions and norepinephrine) in the determinism of CSA-AKI. The CSA-AKI risk was defined by logistic regression analyses with the nadir HCT (%) and the nadir MAP (mmHg) as independent variables and CSA-AKI risk as dependent variable, separately for patients receiving or not RBC transfusions and norepinephrine. Table 1 reports the characteristics of the 200 patients enrolled in the PEQUOD trial, with or without CSA-AKI. The factors composing the MDPI are significantly different between groups and predictive of CSA-AKI (Figure 1). Figure 2 shows the relationship between nadir HCT and CSA-AKI risk in patients receiving or not RBC transfusions. Nine patients out of 200 received RBC transfusions to correct a low HCT; at any nadir HCT, the risk of CSA-AKI is higher in RBC-transfused patients, with a significant for HCT between 19% and 24%. Figure 3 reports the relationship between nadir MAP and CSA-AKI risk for patients receiving or not norepinephrine. Twenty-one patients received epinephrine to correct hypotension on CPB, and had a CSA-AKI risk constantly around 40%, independently from the nadir MAP. The risk of CSA-AKI in the other patients was dependent on the nadir MAP and lower than in patients receiving norepinephrine. The low rate of patients receiving RBC or norepinephrine results in a large 95% confidence interval. The range of nadir HCT were the CSA-AKI risk is significantly lower in patients not transfused is quite common on CPB, and this finding supports a restrictive use of RBC transfusions, conversely suggesting hemoconcentration and/or increased pump flow to preserve the DO2. The use of norepinephrine to treat hypotension episodes seems to be associated with an important increase of CSA-AKI risk. Possible alternatives include increasing pump flow, alternative vasoconstrictors (vasopressin, terlipressin), and other measures (methylene blue, cyanocobalamin). In conclusion, our study suggests that the apparently obvious and current measures to correct hemodilution and hypotension on CPB may actually be more deleterious than beneficial. [ABSTRACT FROM AUTHOR]

Background: Post-cardiotomy extracorporeal membrane oxygenation (ECMO) was associated with significant neurological complications affecting the overall outcome. The aim of the work is to determine the incidence and the predictors of neurological events during pediatric extracorporeal life support after cardiac surgery. Patients & Methods: This is a retrospective study that encompassed all neonates, infants, and children (<18 years of age) who need extracorporeal life support following cardiac surgery between January 2015 and December 2018 at San Donato Hospital, Italy. Data as regards surgical procedure of congenital heart disease, in-hospital mortality, length of ECMO, hospital stay durations, short-term neurological ECMO complications and outcome were analyzed. Results: The sixty-three patients who received post-cardiotomy ECMO, Neurological complications were evident in 31.7% in the form of ischemic stroke in 17.5% and hemorrhagic stroke in 11.1%. By multivariable analysis, the older age of cyanotic cases, the need for a venting cannula, and the rapid CO2 drop in the first 24 h were the most independent risk factors for neurological complications. Prolonged ECMO support and hospital stay duration were associated with neurological sequelae. Conclusion: Neurological complications either ischemic or hemorrhagic strokes were common during pediatric postcardiotomy ECMO and were significantly related to prolonged ECMO support and hospital stay. Predictors of these neurological sequelae are the older cyanotic cases, the need for a venting cannula, the oxygenator thrombosis, and the rapid CO2 drop in the first 24 h of ECMO. [ABSTRACT FROM AUTHOR]

Choices for monitoring of unfractionated heparin (UFH) anticoagulation in extracorporeal membrane oxygenation (ECMO) patients include activated clotting time, activated partial thromboplastin time, reaction times of viscoelastic tests, and anti-factor Xa activity (between 0.3 and 0.7 IU/mL). Recent studies propose the anti-factor Xa to be the gold standard for monitoring UFH anticoagulation in ECMO. However, many extraneous factors combined question the utility of anti-factor Xa as the sole method of monitoring of UFH effects in ECMO. Anti-factor Xa is a chromogenic assay, which may be biased by the frequently elevated values of bilirubin and free hemoglobin in ECMO patients. The test may alternatively underestimate UFH effects in cases of low antithrombin values. More importantly, the anti-factor Xa assay is a plasma-based test which does not take into account the role of platelets and fibrinogen in forming a stable clot. Thrombocytopenia and platelet dysfunction are common features in ECMO patients, and underestimating their role may lead to over-anticoagulation, should only anti-factor Xa guiding be used to adjust the UFH dose. Conversely, fibrinogen is an acute phase protein, and some patients may experience high levels of fibrinogen during the ECMO course. In this case, an UFH monitoring based on anti-factor Xa is insensitive to this condition, although it may potentially be associated with thrombotic complications. Finally, the generally suggested range of 0.3 to 0.7 IU/mL is a somewhat arbitrary estimate, based on the desired range for treating and preventing thrombotic events in non-ECMO patients. In conclusion, anti-factor Xa may offer useful information on the real effects of UFH only when combined with a whole blood test capable of assessing the relative contribution of platelets and fibrinogen to clot formation. [ABSTRACT FROM AUTHOR]

Objective: The nadir hematocrit (HCT) on cardiopulmonary bypass (CPB) is a recognized independent risk factor for major morbidity and mortality in cardiac surgery. The main interpretation is that low levels of HCT on CPB result in a poor oxygen delivery and dysoxia of end organs. Hyperlactatemia (HL) is a marker of dysoxic metabolism, and is associated with bad outcomes in cardiac surgery. This study explores the relationship between nadir HCT on CPB and early postoperative HL. Design: Retrospective study on 3,851 consecutive patients. Measurements and Main Results: Nadir HCT on CPB and other potential confounders were explored for association with blood lactate levels at the arrival in the Intensive Care Unit (ICU), and with the presence of moderate (2.1 – 6.0 mMol/L) or severe (> 6.0 mMol/L) HL. Nadir HCT on CPB demonstrated a significant negative association with blood lactate levels at the arrival in the ICU. After adjustment for the other confounders, the nadir HCT on CPB remained independently associated with moderate (odds ratio 0.96, 95% confidence interval 0.94-0.99) and severe HL (odds ratio 0.91, 95% confidence interval 0.86-0.97). Moderate and severe HL were significantly associated with increased morbidity and mortality. Conclusions: Hemodilution on CPB is an independent determinant of HL. This association, more evident for severe HL, strengthens the hypothesis that a poor oxygen delivery on CPB with consequent organ ischemia is the mechanism leading to hemodilution-associated bad outcomes. [ABSTRACT FROM AUTHOR]

Background: The aim of this study was to assess the association of the coagulation point-of-care (POC) tests activated clotting time (ACT) and thromboelastography-derived parameters reaction time (R-time) and maximum amplitude (MA) with the standard coagulation tests during postcardiotomy extracorporeal membrane oxygenation (ECMO), finding adequate values predictive for the target range of the standard coagulation tests., Methods: Thirty-one patients undergoing postcardiotomy ECMO with heparin anticoagulation were analyzed. Paired data of the POC tests and standard coagulation tests were analyzed for association and positive predictive value (PPV)., Results: The following target range values for standard coagulation test were settled: activated partial thromboplastin time (aPTT) 50-70 seconds; international normalized ratio (INR) 1.5-2.5; platelet count >50,000 cells/µL; fibrinogen >150 mg/dL. The best predictor for the desired aPTT range was an ACT of 162-185 seconds. A combination of an ACT<162 seconds with an R-time <10 minutes had an 83% PPV for a short aPTT. A combination of an ACT>185 seconds with an R-time >27 minutes had a 71% PPV for a long aPTT. No predictive ability of the POC tests was found in terms of the optimal INR range. An MA value <41 mm had a 75% PPV for a low platelet count or fibrinogen level., Conclusions: Diagnostic-therapeutic algorithms based on coagulation POC-tests may be useful to manage anticoagulation during postcardiotomy ECMO. The best PPV for prompting therapeutic decision is provided by a combination of ACT and visco-elastic tests.