Objective To evaluate whether transfusion of cell saver salvaged, stored at the bedside for up to 24 hours, would decrease the number of post-operative allogeneic RBC transfusions and donor exposures, and possibly improve clinical outcomes. Design Prospective, randomized, controlled, clinical trial. Setting Pediatric cardiac intensive care unit. Patients Infants <20kg (n = 106) presenting for cardiac surgery with cardiopulmonary bypass. Interventions Subjects were randomized to a cell saver transfusion group where cell saver blood was available for transfusion up to 24 hours post-collection, or to a control group. Cell saver subjects received cell saver blood for volume replacement and/or RBC transfusions. Control subjects received crystalloid or albumin for volume replacement and RBCs for anemia. Blood product transfusions, donor exposures, and clinical outcomes were compared between groups. Measurements and Main Results Children randomized to the cell saver group had significantly fewer RBC transfusions (cell saver: 0.19 ± 0.44 v. control: 0.75 ± 1.2; p = 0.003) and coagulant product transfusions in the first 48 hours post-op (cell saver: 0.09 ± 0.45 v. control: 0.62 ± 1.4; p = 0.013), and significantly fewer donor exposures (cell saver: 0.60 ± 1.4 v. control: 2.3 ± 4.8; p =0.019). This difference persisted over the first week post-op, but did not reach statistical significance (cell saver: 0.64 ± 1.24 v. control: 1.1 ± 1.4; p =0.07). There were no significant clinical outcome differences. Conclusion Cell saver blood can be safely stored at the bedside for immediate transfusion for 24 hours post-collection. Administration of cell saver blood significantly reduces the number of RBC and coagulant product transfusions and donor exposures in the immediate post-operative period. Reduction of blood product transfusions has the potential to reduce transfusion-associated complications and decrease post-operative morbidity. Larger studies are needed to determine whether this transfusion strategy will improve clinical outcomes.

This Boot Camp session introduced residents early in their training to aortic cannulation, principles and management of cardiopulmonary bypass, and crisis management. Based on a modular approach, technical skills and knowledge of cardiopulmonary bypass can be acquired and assessed by using simulations, but further work with more comprehensive educational modules and practice will accelerate the path to mastery of these critical skills.

BACKGROUND: Currently no ideal alternative exists for heparin for cardiopulmonary bypass (CPB). Dabigatran is a direct thrombin inhibitor for which a reversal agent exists. The primary end point of the study was to explore whether Dabigatran was an effective anticoagulant for 120 minutes of simulated CPB. METHODS: The study was designed in 2 sequential steps. Throughout, human blood from healthy donors was used for each experimental step. Initially, increasing concentrations of Dabigatran were added to aliquots of fresh whole blood, and the anticoagulant effect measured using kaolin/tissue factor–activated thromboelastography (rapidTEG). The dynamics of all thromboelastography (TEG) measurements were studied with repeated measures analysis of variance (ANOVA). Based on these data, aliquots of blood were treated with high-concentration Dabigatran and placed in a Chandler loop as a simple ex vivo bypass model to assess whether Dabigatran had sufficient anticoagulant effects to maintain blood fluidity for 2 hours of continuous contact with the artificial surface of the PVC tubing. Idarucizumab, humanized monoclonal antibody fragment, was used to verify the reversibility of Dabigatran effects. Finally, 3 doses of Dabigatran were tested in a simulated CPB setup using a heart–lung machine and a commercially available bypass circuit with an arteriovenous (A-V) loop. The primary outcome was the successful completion of 120 minutes of simulated CPB with dabigatran anticoagulation, defined as lack of visible thrombus. Thromboelastographic reaction (R) time was measured repeatedly in each bypass simulation, and the circuits were continuously observed for clot. Scanning Electron Microscopy (SEM) was used to visualize fibrin formation in the filters meshes during CPB. RESULTS: In in vitro blood samples, Dabigatran prolonged R time and reduced the dynamics of clot propagation (as measured by speed of clot formation [Angle], maximum rate of thrombus generation [MRTG], and time to maximum rate of thrombus generation [TMRTG]) in a dose-dependent manner. In the Chandler Loop, high doses of Dabigatran prevented clot formation for 120 minutes, but only at doses higher than expected. Idarucizumab decreased R time and reversed anticoagulation in both in vitro and Chandler Loops settings. In the A-V loop bypass simulation, Dabigatran prevented gross thrombus generation for 120 minutes of simulated CPB. CONCLUSIONS: Using sequential experimental approaches, we showed that direct thrombin inhibitor Dabigatran in high doses maintained anticoagulation of blood for simulated CPB. Idarucizumab reduced time for clot formation reversing the anticoagulation action of Dabigatran.

Background Antifibrinolytic medications such as epsilon-aminocaproic acid (EACA) are used in pediatric heart surgery to decrease surgical bleeding and transfusion. Dosing schemes for neonates are often based on adult regimens, or are simply empiric, in part due to the lack of neonatal pharmacokinetic information. We sought to determine the pharmacokinetics of EACA in neonates undergoing cardiac surgery and to devise a dosing regimen for this population. Methods Ten neonates undergoing cardiac surgery with cardiopulmonary bypass were given EACA according to standard practice, and blood was drawn at 10 time points to determine drug concentrations. Time-concentration profiles were analyzed using nonlinear mixed effects models. Parameter estimates (standardized to a 70 kg person) were used to develop a dosing regimen intended to maintain a target concentration shown to inhibit fibrinolysis in neonatal plasma (50 mg/L). Results Pharmacokinetics were described using a two compartment model plus an additional compartment for the cardiopulmonary bypass pump. First order elimination was described with a clearance of 5.07 L/h*(WT/70) 0.75. Simulation showed a dosing regimen with a loading dose of 40 mg/kg, and an infusion of 30 mg/kg/h, with a pump prime concentration of 100 mg/L maintained plasma concentrations above 50 mg/L in 90% of neonates during cardiopulmonary bypass surgery. Conclusions EACA clearance, expressed using allometry, is reduced in neonates compared to older children and adults. Loading dose and infusion dose are approximately half those required in children and adults.