Incidence, Risk Factors, and Outcomes of Hyperbilirubinemia in Adult Cardiac Patients Supported by Veno-Arterial ECMO.

The aims of this study were to evaluate the incidence, risk factors, and outcomes of hyperbilirubinemia in cardiac patients with veno-arterial (VA) ECMO. Data on 89 adult patients with cardiac diseases who received VA ECMO implantation in our hospital were retrospectively reviewed. All patients were divided into the following three groups: 24 in normal group (N, total bilirubin [TBIL] ≤3 mg/dL), 30 in high bilirubin group (HB, 6 mg/dL ≥ TBIL > 3 mg/dL), and 35 in severe high bilirubin group (SHB, TBIL > 6 mg/dL). lg(variables + 1) was performed for nonnormally distributed variables. The incidence of hyperbilirubinemia (>3 mg/dL) was 73%. In a multiple linear regression analysis, lg(peak TBIL + 1) was significantly associated with lg(peak AST + 1) (b-coefficient 0.188, P = 0.001), lg(peak pFHb + 1) (b-coefficient 0.201, P = 0.003), and basic TBIL (b-coefficient 0.006, P = 0.009). Repeated measurement analysis of variance revealed that the main effect for three groups in pFHb and lg(AST + 1) was significant at first 3 days during ECMO. The patients in SHB had low platelets during ECMO and low in-hospital survival rate. Hyperbilirubinemia remains common in patients with VA ECMO and is associated with low platelets and high in-hospital mortality. Hemolysis and liver dysfunction during ECMO and basic high bilirubin levels are risk factors of hyperbilirubinemia.

Predictors of Acute Renal Failure During Extracorporeal Membrane Oxygenation in Pediatric Patients After Cardiac Surgery.

Acute renal failure (ARF) is associated with increased mortality in pediatric extracorporeal membrane oxygenation (ECMO). The aim of this study was to identify predictors of ARF during ECMO in pediatric patients after cardiac surgery. A retrospective study analyzed 42 children (≤15 years) after cardiac surgery requiring venous-arterial ECMO between December 2008 and December 2014 at Fuwai Hospital. ARF was defined as ≥300% rise in serum creatinine (SCr) concentration from baseline or application of dialysis. Multivariate logistic regression was performed to identify the predictors of ARF during ECMO. A total of 42 children (age, interquartile range [IQR], 13.0 [7.2-29.8] months; weight, IQR, 8.5 [6.7-11.0] kg) after cardiac surgery requiring ECMO were included in this study. The total survival rate was 52.4%, and the incidence of ARF was 40.5%. As the result of univariate analysis, ECMO duration, cardiopulmonary resuscitation, maximum free hemoglobin (FHB) during ECMO, lactate level, and mean blood pressure before initiation of ECMO were entered in multiple logistic regression analysis. In multiple logistic regression analysis, FHB during ECMO (OR 1.136, 95% CI 1.023-1.261) and lactate level before initiation of ECMO (OR 1.602, 95% CI 1.025-2.502) were risk factors for ARF during ECMO after pediatric cardiac surgery. There was a linear correlation between maximum SCr and maximum FHB (Pearson's r = 0.535, P = 0.001). Maximum SCr during ECMO has also a linear correlation with lactate level before initiation of ECMO (Pearson's r = 0.342, P = 0.044). Increased FHB during ECMO and high lactate level before initiation of ECMO were risk factors for ARF during ECMO in pediatric patients after cardiac surgery.

Plasma Free Hemoglobin Is a Predictor of Acute Renal Failure During Adult Venous-Arterial Extracorporeal Membrane Oxygenation Support.

OBJECTIVE: Hemolysis is a common and severe complication during extracorporeal membrane oxygenation (ECMO). Increased plasma free hemoglobin (PFHb) is related to renal injury. The aim of this study was to investigate whether increased PFHb during adult venous-arterial ECMO was associated with acute renal failure (ARF). DESIGN: A retrospective, observational, single-center study. SETTING: Fuwai Hospital in Beijing, China. PARTICIPANTS: The study comprised 84 venous-arterial ECMO patients. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: A total of 84 consecutive adult patients (≥18 years) with cardiac diseases requiring venous-arterial ECMO support were studied retrospectively. Demographics of patients, clinical and ECMO characteristics, and PFHb level were collected within the first 3 days after ECMO. ARF was defined as a≥300% rise in serum creatinine from baseline or application of dialysis. Repeated measurement analysis of variance revealed that the main effect for the non-ARF group and ARF group in PFHb (p = 0.002) was significant. A significant main effect for time points (p<0.001) and time×group interaction (p = 0.014) in PFHb was obtained. In a multiple logistic regression model, peak PFHb during ECMO (odds ratio 1.052, 95% confidence interval 1.016-1.089, p = 0.005) was a risk factor for ARF during ECMO and patients who underwent heart transplantation (odds ratio 0.240, 95% confidence interval 0.060-0.964, p = 0.044) experienced less ARF. There was a linear correlation between peak serum creatinine and peak PFHb (Spearman's r = 0.223, p = 0.042). CONCLUSIONS: Increased PFHb is a predictor of ARF among adult patients on venous-arterial ECMO support.

Effects of circuit albumin coating on coagulation and inflammatory response for patients receiving aortic arch replacement: a randomized controlled trial.

OBJECTIVE: To investigate whether human serum albumin coating before cardiopulmonary bypass (CPB) could improve platelet function and hemostasis and mitigate the inflammatory response among patients receiving aortic arch replacement with deep hypothermic circulatory arrest (DHCA). METHODS: Sixty patients were included and randomized into two groups: the Control Group (CG, receiving 40 g human albumin 5 minutes after the initiation of CPB) and the Study Group (SG, circulating the prime with 40 g albumin for 5 minutes before CPB). Rapid thromboelastography, complete blood count, coagulation tests and cytokines (IL-1, IL-6, IL-10, TNF-α and PAF) were measured at two intervals: after anesthesia induction and before CPB (T1) and 10 minutes after heparin reversal before any blood product transfusion (T2). RESULTS: Compared with T1, the fibrinogen and MA levels in both groups reduced significantly after heparin reversal and fell within the normal range for most patients. The platelet count reduction (ΔPLT) in the Study Group was significantly less than in the Control Group (p=0.031). Despite the inflammatory factor levels increasing after CPB (p<0.001), no differences were found between the Control Group and the Study Group. Fewer red blood cells were given in the Study Group, but this was not significant (p=0.05). CONCLUSION: Most patients receiving aortic arch replacement with DHCA have normal platelet function and fibrinogen levels after heparin reversal. Albumin coating before CPB may mitigate the platelet count reduction, but not platelet dysfunction. There is a trend that the patients treated with albumin coating received less red blood cell transfusions.

Histidine-tryptophan-ketoglutarate solution with added ebselen augments myocardial protection in neonatal porcine hearts undergoing ischemia/reperfusion.

Whether modified histidine-tryptophan-ketoglutarate (HTK) solution offers myocardial protection to newborn heart has not been documented. The purpose of this study was to compare myocardial protection using HTK added by ebselen with HTK in a piglet model of cardiopulmonary bypass (CPB). Fifteen piglets were randomly assigned to three groups: the control group (C group, n = 5), HTK solution group (HTK group, n = 5), and HTK added by 10 nM ebselen group (HTK+E group, n = 5). Animals in the two experimental groups were placed on hypothermic CPB, after which the ascending aorta had been clamped for 2 h. The control animals underwent normothermic CPB without cardiac arrest. Myocardial antioxidant activities, myocytes apoptosis and mitochondrial structures, as well as the release of cytochrome c and the expression of Bax, Bcl-2, and HSP72 protein in myocardium were measured. Increased myocardial superoxide dismutase (SOD) and Mn-SOD activities, decreased TUNEL-positive cells, and reduced release of cytochrome c were noted in the HTK+E group compared with those in the HTK group (P = 0.021, P = 0.020, P = 0.045, and P = 0.010, respectively). The Bax/Bcl-2 ratio in the HTK group was significantly higher than that in the C group (P = 0.024). The expression of HSP72 protein and mRNA in the HTK+E group was higher than that in the HTK group (P = 0.039 and P = 0.035, respectively). Mitochondrial score under electron microscope in the HTK+E group was lower than that in the HTK group (P = 0.047). Improved antioxidant defense, reduced myocytes apoptosis, and better preserved mitochondrial structure were observed in the HTK+E group. Ebselen added to HTK provides better myocardioprotection to HTK solution for the neonatal heart.

The influence of cardiopulmonary bypass priming without FFP on postoperative coagulation and recovery in pediatric patients with cyanotic congenital heart disease.

UNLABELLED: Transfusion guidelines have been produced for the evidence-based use of fresh frozen plasma (FFP). However, the inappropriate use of FFP is still a worldwide problem, especially in the prophylactic settings. In the present study, 100 cyanotic pediatric patients (age 6 months to 3 years) undergoing cardiac surgery with cardiopulmonary bypass (CPB) were randomized to receive either 10-20 ml/kg FFP (FFP group, n = 50) or 10-20 ml/kg 4 % succinylated gelatin (Gelofusine, GEL group, n = 50) in the priming solution. Rapid thromboelastography (r-TEG) was measured before skin incision and 15 min after heparin neutralization. Postoperative renal and hepatic function, mediastinal chest tube drainage, transfusion requirements, and recovery time were observed. The relationships between hematologic and demographic data and postoperative bleeding volume were also analyzed. The results showed that there were significantly elevated levels of fibrinogen (r-TEG parameters: fibrinogen contribution to maximal amplitude (MAf) and fibrinogen level (FLEV)) in the FFP group compared to the GEL group. The postoperative blood loss, total transfusion requirements, and recovery time were not significantly different between the two groups, indicating that there were no obvious clinical benefits of using FFP in the priming. The maximal amplitude (MA) of r-TEG measured after heparin neutralization was correlated with the 6-h postoperative bleeding volume. In addition, preoperative fibrinogen level rather than FFP priming was an independent predictor of postoperative blood loss. CONCLUSION: Prophylactic use of FFP in the priming solution does not have obvious clinical benefits in cyanotic congenital heart disease (CCHD) patients. Gelofusine, an artificial colloid, is a safe and effective substitute of FFP in the priming solution. Furthermore, r-TEG can be used as a "real-time" assessment tool to evaluate postoperative bleeding and guide transfusion after cardiac surgery in pediatric patients.

The dynamic observation of plasma concentration of antimicrobial agents during balanced ultrafiltration in vitro.

Routine perioperative intravenous antimicrobial agents are administered as surgical prophylaxis. However, whether balanced ultrafiltration during extracorporeal circulation has substantial effect on the concentration of antimicrobial agents remains unclear. The concentrations of antimicrobial agents in plasma and ultrafiltrate samples were measured in this pseudo-extracorporeal circulation model. Extracorporeal circulation consisted of cardiotomy reservoir, membrane oxygenator, and pediatric arterial line filter. A hemoconcentrator was placed between the arterial purge line and oxygenator venous reservoir. Fresh donor human whole blood was added into the circuit and mixed with Ringer's solution to obtain a final hematocrit of 24-28%. Two kinds of antimicrobial agents, cefotiam (320 mg) and cefmetazole (160 mg), were bolus added into the circuit. After 30 min of extracorporeal circulation, zero-balanced ultrafiltration was initiated and arterial line pressure was maintained at approximately 100 mm Hg with a Hoffman clamp. The rate of ultrafiltration (12 mL/min) was controlled by ultrafiltrate outlet pressure. An identical volume of Plasmalyte A was dripped into the circuit to maintain stable hematocrit during 45 min of experiment. Plasma and ultrafiltrate samples were drawn every 5 min, and concentrations of antimicrobial agents (including cefotiam and cefmetazole) were measured with high performance liquid chromatography. Both antimicrobial agents were detected in ultrafiltrate, demonstrating hemoconcentration may remove antimicrobial agents. The concentrations of plasma antimicrobial agents decreased linearly with the increase of ultrafiltrate volume. At end of balanced ultrafiltration, the concentration of plasma cefotiam was 104.96 ± 44.36 mg/L, which is about 44.38% ± 7.42% of the initial concentration (238.95 ± 101.12 mg/L) (P < 0.001); the concentration of plasma cefmetazole decreased linearly to 25.76 ± 14.78 mg/L, which is about 49.69% ± 10.49% of the initial concentration (51.49 ± 28.03 mg/L) (P < 0.001). The total amount of cefotiam in ultrafiltrate is 27.16% ± 12.17% of the total dose administered, whereas cefmetazole in ultrafiltrate is 7.74% ± 4.17%. Balanced ultrafiltration may remove antimicrobial agents from plasma and has a prominent influence on plasma concentration of antimicrobial agent. The strategy of surgical prophylaxis should consider this unique technique during extracorporeal circulation.

[Effects of multidisciplinary blood management strategy on transfusion and outcomes in patients undergoing valvular heart surgery].

UNLABELLED: To evaluate the effect of multidisciplinary blood management strategy in adults patients undergoing valvular heart surgery. METHODS: A multidisciplinary patient blood management (PBM) strategy was instituted in Fuwai Hospital since January 2009. It includes Establishment of a multidisciplinary blood transfusion management team and designation of a coordinator; Enactment perioperative transfusion triggers (Hb < 80 g/L) for adults patients undergoing cardiac surgery; recommendation of antifibrinolytics, cell salvage, reduced cardiopulmonary bypass circuit; setting up Blood Consumption Announcement and Scoring System, which regularly publishes notifications of blood volume consumed per case, per single procedure and per surgeon. Clinical date before and after multidisciplinary patient blood management strategy will be presented. RESULTS: A total of 3 951 consecutive patients underwent Valvular Heart Surgery were analyzed. 1 713 cases were in pre-PBM group, and 2 238 cases were in post-PBM group. Both incidence and average units of allogeneic red blood cell transfusion perioperatively in post-PBM group were decreased (28.5% vs 75.3%, P = 0.000, and 1.2 U vs 4.0 U, P = 0.000). The postoperative length of stay in hospital and incidence of pneumonia were reduced in post-PBM group (8.2 d vs 10.5 d, P = 0.02, and 2.7% vs 3.5%, P = 0.04). The post-PBM group had lower in-hospital mortality (0.6% vs 1.2%, P = 0.000). CONCLUSION: Multidisciplinary patient blood management strategy significantly reduced blood transfusion, morbidity and mortality in patients underwent valvular heart surgery. It save plenty of blood resources.

The protective effect of St. Thomas cardioplegia enriched with zacopride on the isolated rat heart.

The activation of the heart inward rectifier potassium channel (I(K1) ) can reduce the injury of myocardial cells by shortening the action potential duration and reducing intracellular calcium overload. Zacopride is a selective I(K1) agonist and suppresses triggered arrhythmias in rat hearts. This investigation studied the effects of St. Thomas (ST) cardioplegia enriched with Zacopride on the isolated rat heart model. Sprague-Dawley rat hearts were harvested and perfused for 20 minutes with 37°C Krebs-Henseleit (KH) buffer followed by 15 minute perfusion with 4°C calcium-free KH buffer in the Control group (Con, n = 8), ST cardioplegia in the ST group (ST, n = 8) and ST cardioplegia with Zacopride in the STZ group (STZ, n = 8). After 45 minutes of arresting, all hearts were reperfused with 37°C KH buffer for 60 minutes. Hearts in the STZ group arrested faster than the Con and ST groups (9.25 ± 2.38 s vs. 72.25 ± 8.1 s, 12.75 ± 2.87 s). The recovery of the left ventricular developed pressure, ± dP/dtmax, heart rate, and coronary flow in the STZ group is significantly better than the other two groups during reperfusion. Compared with the Con and ST groups, the STZ group showed significant decreases in the maximum carciac troponin I level (P < 0.05) and the infarct size (P < 0.05). The superoxide dismutase level in the STZ group increased during the first 20 minutes of reperfusion (P < 0.05). ST cardioplegia enriched with Zacopride has beneficial effects against ischemia-reperfusion injury in this isolated rat heart model.

Expression of microRNA-1 and microRNA-21 in different protocols of ischemic conditioning in an isolated rat heart model.

BACKGROUND: 'Conditioning' [ischemic preconditioning (IPC), ischemic postconditioning (IPO) and remote ischemic preconditioning (RIPC)] the heart to render it more resistant to an episode of acute myocardial ischemia-reperfusion (I/R) injury is an endogenous cardioprotective strategy. There are several mechanisms proposed for 'conditioning', such as endogenous mediators or cytoprotective proteins. In recent reports, microRNAs (miRNAs) were involved in controlling the expression of myocardial ischemia-related genes. Some studies have demonstrated that cardiac miRNA-1 and miRNA-21 were significantly increased by late IPC with an increase in their target proteins [endothelial nitric oxide synthase and heat shock protein 70 (HSP70)], but their expression levels in 'conditioning' strategies are currently unknown. METHODS: In the current study, Langendorff-perfused Sprague-Dawley rat hearts were randomly assigned to one of four groups [control group (CON group, n = 12), IPC group (n = 12), IPO group (n = 12) and RIPC group (n = 12)]. Cardiac function was digitalized and analyzed. The expression of miRNA-1 and miRNA-21 was detected by real-time reverse transcription polymerase chain reaction. The expression of HSP70, programmed cell death protein 4 (PDCD4), B-cell lymphoma/leukemia-2 (Bcl-2) and Bcl-2-associated X protein (Bax) was detected by Western blot. Cardiac infarct size and myocardial apoptosis were determined using the 2,3,5-triphenyltetrazolium chloride assay and terminal deoxynucleotidyl transferase dUTP nick end labeling assay, respectively. RESULTS: The results revealed that miRNA-1 (233 ± 45%) and miRNA-21 (356 ± 33%) expression was up-regulated in the IPC group, but the expression of miRNA-1 was down-regulated in the RIPC (61 ± 16%) group and IPO group (61 ± 13%). The expression of PDCD4 [IPC (74 ± 11%), RIPC (81 ± 16%), IPO (83 ± 12%)], HSP70 [IPC (74 ± 5%), RIPC (81 ± 6%), IPO (67 ± 11%)] and Bax [IPC (27 ± 6%), RIPC (21 ± 3%), IPO (27 ± 4%)] was down-regulated in the conditioning groups compared with the CON group [PDCD4 (130 ± 11%), HSP70 (121 ± 11%) and Bax (63 ± 8%)]. In the conditioning hearts, infarct size [IPC (31.7 ± 4.1%), RIPC (29.6 ± 6.19%) and IPO (32.8 ± 4.71%)] and myocardial apoptosis [IPC (15.2 ± 4.21%), RIPC (17.2 ± 1.92%) and IPO (15.6 ± 4.04%)] were significantly decreased compared with the CON group (infarct size: 51.77 ± 4.3%, myocardial apoptosis: 32.8 ± 3.96%). CONCLUSION: We concluded that miRNA-1 and miRNA-21 expression differed in IPC, RIPC and IPO groups, and their target proteins were not inversely correlated with the miRNAs in all the conditioning groups, which revealed that the miRNAs were regulated but complicated by the different conditioning protocols.

Balanced ultrafiltration: inflammatory mediator removal capacity.

Ultrafiltration with a hemoconcentrator may remove excess fluid load and alleviate tissue edema and has been universally adopted in extracorporeal circulation protocols during pediatric cardiac surgery. Balanced ultrafiltration is advocated to remove inflammatory mediators generated during surgery. However, whether balanced ultrafiltration can remove all or a portion of the inflammatory mediator load remains unclear. The inflammatory mediator removal capacity of zero-balanced ultrafiltration was measured during pediatric extracorporeal circulation in vitro. Extracorporeal circulation was composed of cardiotomy reservoir, D902 Lilliput 2 membrane oxygenator, and Capiox AF02 pediatric arterial line filter. The Hemoconcentrator BC 20 plus was placed between arterial purge line and oxygenator venous reservoir. Fresh donor human whole blood was added into the circuit and mixed with Ringer's solution to obtain a final hematocrit of 24-28%. After 2 h of extracorporeal circulation, zero-balanced ultrafiltration was initiated and arterial line pressure was maintained at approximately 100 mmHg with Hoffman clamp. The rate of ultrafiltration (12 mL/min) was controlled by ultrafiltrate outlet pressure. Identical volume of plasmaslyte A was dripped into the circuit to maintain stable hematocrit during the 45 min of the experiment. Plasma and ultrafiltrate samples were drawn every 5 min, and concentrations of inflammatory mediators including interleukin-1ß (IL-1ß), IL-6, IL-10, neutrophil elastase (NE), and tumor necrosis factor-α (TNF-α) were measured. All assayed inflammatory mediators were detected in the ultrafiltrate, demonstrating that the ultrafiltrator may remove inflammatory mediators. However, dynamic observations suggested that the concentration of NE was highest among the five inflammatory mediators in both plasma and ultrafiltrate (P < 0.001). IL-1ß had the lowest concentration in plasma, whereas the concentration of TNF-α was the lowest in ultrafiltrate (P < 0.001). Concentrations of all inflammatory mediators in the ultrafiltrate did not increase linearly compared with those in plasma. The respective ultrafiltrate to plasma concentration and amount ratios indicated that the total removal effect of hemoconcentrator on the inflammatory mediators was 4.17 ± 2.68% for IL-1ß, 0.64 ± 0.69% for IL-6, 0.24 ± 0.18% for IL-10, 2.84 ± 1.65% for NE, and 0.51 ± 0.81% for TNF-α, respectively. Balanced ultrafiltration may selectively remove inflammatory mediators from serum. Respective ratios of inflammatory mediators in ultrafiltrate compared with plasma, as well as total amount of inflammatory mediators in the ultrafiltrate suggest that balanced ultrafiltration removes a limited portion of the total inflammatory mediator load.

Comparison of the effects of three cell saver devices on erythrocyte function during cardiopulmonary bypass procedure--a pilot study.

Cell salvage devices are routinely used to process red blood cells (RBCs) shed during cardiac surgery. The purpose of this study was to evaluate three commercially available cell saver (CS) devices in terms of erythrocyte function and the quality of washed RBCs during cardiopulmonary bypass (CPB). Thirty patients undergoing CPB were randomly allocated to three CS devices: Group C (Cell Saver 5+; Haemonetics, n = 10), Group M (autolog; Medtronic, n = 10), and Group F (CATS; Fresenius HemoCare, n = 10). Blood samples were collected from reservoirs and transfusion bags. Reservoirs and washed RBCs were analyzed for erythrocyte aggregation index, deformation index (DI) and hematocrit viscosity, 2,3-diphosphoglycerate (2,3-DPG), hematocrit (Hct), hemoglobin (Hb), free Hb removal (ΔfHb), glucose (Glu), lactate (Lac), and blood urea nitrogen. After processing, Groups C (P = 0.026) and M (P = 0.032) had relatively higher erythrocyte DI compared with Group F. Group C had lower Δ2,3-DPG compared with Groups M (P = 0.001) and F (P = 0.001). Group F provided the maximum concentration of Hct (P = 0.021; 0.046) and Hb (P = 0.008; 0.013). In addition, Groups C (P = 0.035) and M (P = 0.038) had a higher removal of fHb (ΔfHb), differing significantly with Group F. In conclusion, CS devices use the same theory of centrifugation; however, based on different designs, the function of the washed erythrocyte and undesirable content removal efficiency differs widely from one device to another.

The optimal flow rate for antegrade cerebral perfusion during deep hypothermic circulatory arrest.

The aim of this study is to compare cerebral protection using antegrade cerebral perfusion (ACP) with various flow rates during deep hypothermic circulatory arrest (DHCA) in a piglet model. Twenty-three piglets were randomized to five groups: the control group (n = 3), DHCA group (n = 5), ACP25 group (n = 5), ACP50 group (n = 5), and ACP80 group (n = 5). Three control piglets did not undergo operations. Twenty piglets underwent cardiopulmonary bypass (CPB) and DHCA for 60 min at 20°C. ACP was conducted at 0, 25, 50, and 80 mL/kg/min in the DHCA, ACP25, ACP50, and ACP80 group, respectively. Serum S-100B protein and neuron-specific enolase were monitored, and brain tissues were assayed for the activities of caspase-3 and stained for the evidence of apoptotic cellular injury. Rise in serum S-100B level (post-CPB-pre-CPB) in the ACP50 group was significantly lower than that in the ACP80 group (P = 0.001). Caspase-3 levels were significantly elevated in the ACP80 group compared with the ACP25 (P = 0.041) and ACP50 group (P = 0.01), while positive terminal deoxyneucleotidyl transferase-mediated biotin-dUTP nick end labeling reaction scores in the ACP80 group were significantly higher than those in the ACP25 (P = 0.043) and ACP50 group (P = 0.023). Cerebral protection effects of ACP at 25 and 50 mL/kg/min were superior to that of ACP at 80 mL/kg/min as determined by cerebral markers, immunology, and histology.

Effects of pulsatile and nonpulsatile perfusion on cerebral regional oxygen saturation and endothelin-1 in tetralogy of fallot infants.

Although benefits of pulsatile flow during cardiopulmonary bypass (CPB) in pediatric heart surgery remain controversial and nonpulsatile CPB is still widely used in clinical cardiac surgery, pulsatile CPB must be reconsidered due to its physiologic features. In this study, we aimed to evaluate the effects of pulsatile perfusion (PP) and nonpulsatile perfusion (NP) on cerebral regional oxygen saturation (rSO2) and endothelin-1 (ET-1) in pediatric tetralogy of Fallot (TOF) patients undergoing open heart surgery with CPB. Forty pediatric patients were randomly divided into the PP group (n = 20) and the NP group (n = 20). Pulsatile patients used a modified roller pump during the cross-clamp period in CPB, while NP patients used a roller pump with continuous flat flow perfusion. The subjects were monitored for rSO2 from the beginning of the operation until 6 h after returning to the intensive care unit (ICU). We also monitored the hemodynamic status and ET-1 concentration and plasma free hemoglobin (PFH) in blood samples of all patients over time. Effective PP was monitored in PP patients, and pulse pressure was significantly higher in the PP group than in the NP group (P < 0.01). rSO2 of the PP group was higher than that of the NP group (P < 0.01) during the cross-clamp period, and this advantage of PP would be maintained until 2 h after patients returned to the ICU (P < 0.05). ET-1 level in blood samples was lower at clamping off and CPB weaning and early ICU period in the PP group than in the NP group (P < 0.01), and ET-1 concentration remained at a normal level after patients were transferred to the ICU 24 h in all patients. PFH levels in the PP group at pre-clamp off and CPB weaned off were higher than those of the NP group (P < 0.05) in these cyanotic patients. PP can increase rSO2 and improve microcirculation during cross-clamping period in TOF pediatric patients, while PP resulted in more severe hemolysis in these cyanotic patients than NP.

Clinical evaluation of two different extracorporeal membrane oxygenation systems: a single center report.

Refinements in extracorporeal membrane oxygenation (ECMO) equipment, including heparin-coated surfaces, centrifugal pump, membrane oxygenator, and more biocompatible pump-oxygenator circuits, have reduced procedure-related complications and have made ECMO a safe and effective therapy for critical patients. The aim of this study was to evaluate the performance of two different ECMO circuit systems in a clinical setting and compare their outcomes. From December 2004 to December 2009, 121 patients required ECMO for primary or postcardiotomy cardiogenic shock at our heart center. We used the Medtronic circuit system in our earlier series (Group M, n = 64), and from July 2007, ECMO was carried out mainly with the Quadrox D PLS circuit system (Group Q, n = 56). We retrospectively summarized and analyzed the data of these patients. The evaluation was based on the comparison between properties of the membrane oxygenators and pumps, anticoagulation therapy, circuit-related complications, and clinical outcomes. Support pump flow rates, platelet counts, and trans-membrane pressure drops (TMPDs) of preoxygenator and postoxygenator pressures were compared between two groups at the time of support established (T1) and support established for 24 h (T2). There were no significant differences between the two groups with regard to patient characteristics and pre-ECMO data. The support pump flow rates and platelet counts at different times were comparable in the two groups. The cannulation technique, ECMO duration, and mean heparin dosage were similar in both groups. There were also no significant differences between the groups in mortality or complications related to bleeding and organ dysfunction. Compared with the M group, the Q group experienced less mechanical failure of the ECMO circuit. The Quadrox PLS circuit system showed less circuit thrombus formation (P < 0.045), less plasma leakage (P < 0.001), and less need for replacement of oxygenators (P < 0.001). Furthermore, frequency of hemolysis during ECMO was significantly lower (P < 0.045). In addition, at T1 and T2, TMPDs were significantly lower in the Q group. Our results suggest that both ECMO circuit systems provide similar effects for safe clinical application, but the Quadrox PLS ECMO circuit system demonstrated partially improved biocompatibility in terms of improved cell preservation, lower TMPDs, less plasma leakage, and thrombus formation.

Five-year results of 121 consecutive patients treated with extracorporeal membrane oxygenation at Fu Wai Hospital.

Since 2004, our institution has adopted venoarterial (VA) extracorporeal membrane oxygenation (ECMO) for patients who otherwise could not be weaned from cardiopulmonary bypass and patients experiencing cardiogenic shock and/or pulmonary dysfunction unresponsive to conventional treatments. In this study, we reviewed our experience with ECMO support and tried to identify predictors of in-hospital mortality. We retrospectively analyzed the clinical records of 121 consecutive patients receiving ECMO. Patients were divided into adult and pediatric groups and analyzed separately. Demographics, clinical characteristics at the time of ECMO implantation, ECMO-related complications, and in-hospital mortality were collected. Logistic regression analyses were performed to investigate predictors of mortality. A P value ≤ 0.05 was accepted as significant. Sixty-eight adult patients and 53 pediatric patients were included in this study. In adult patients, 52 were weaned from ECMO and 43 survived upon discharge. After univariate analysis, ECMO setup location, receiving cardiopulmonary resuscitation before ECMO, leg ischemia, hemolysis, acute renal failure (ARF), neurological dysfunction, and multiple organ dysfunction syndrome were associated with in-hospital death. In multiple logistic regression analyses, leg ischemia (OR 14.68, 95% CI 1.67-129.1), ARF (OR 12.14, 95% CI 2.5-58.8), and neurological dysfunction (OR 49.0, 95% CI 2.28-1051.96) were risk factors associated with in-hospital mortality. Patients put on ECMO in the operating room had a better chance of survival (OR 0.078, 95% CI 0.013-0.417). In pediatric patients, 30 were weaned from ECMO and 26 survived upon discharge. After univariate analysis, age, weight, and eight ECMO complications were associated with in-hospital death. In multiple logistic regression analyses, ARF (OR 24.0, 95% CI 4.2-137.3) was a risk factor associated with in-hospital mortality. A P value of 0.921 and >0.99 was obtained by the Hosmer-Lemeshow test, and the area under the curve was 0.863 and 0.867 for adult and pediatric patients, respectively. The overall survival rate was 57%. ECMO is a justifiable alternative treatment for refractory cardiac and/or pulmonary dysfunction which could rescue more than 50% of carefully selected patients. Higher survival rates could be achieved by preventing ECMO complications.

Acidic buffer or plus cyclosporine a postconditioning protects isolated rat hearts against ischemia-reperfusion injury.

BACKGROUND: It is well documented that transient acidosis during reperfusion is protective. The aim of this study was to evaluate the cardioprotection of acidic buffer or plus cyclosporine A in isolated rat hearts after cardioplegic arrest. METHODS: Langendorff-perfused Sprague-Dawley rat hearts were perfused for 20 min with Krebs-Henseleit (K-H) buffer followed by 30 min of crystalloid cardioplegia and 60 min of reperfusion. Control hearts were perfused with Krebs-Henseleit buffer. Acidic buffer post-conditioning hearts were perfused with acidic K-H buffer (pH 6.8) for the first 3 min of reperfusion. Acidic buffer plus cyclosporine A hearts were perfused with K-H acidic buffer (pH 6.8) containing cyclosporine A (0.2 µmol/L) for the first 3 min of reperfusion. RESULTS: Compared with the control group, acidic buffer or plus cyclosporine A post-conditioning significantly improved myocardial performance, decreased cytochrome C release into the cytosol, increased Bcl-2 expression and decreased Bax expression, decreased sensitivity of mPTP-opening to [Ca2+] and the rate of apoptosis after reperfusion. CONCLUSION: These findings suggested that acidic buffer or plus cyclosporine A post-conditioning prevented apoptosis-related mitochondrial permeabilization and provided the myocardial protection after cardioplegic arrest.

Acidic buffer or plus cyclosporine A post-conditioning protects isolated rat hearts against ischemia-reperfusion injury.

BACKGROUND: It is well documented that transient acidosis during reperfusion is protective. The aim of this study was to evaluate the cardioprotection of acidic buffer or plus cyclosporine A in isolated rat hearts after cardioplegic arrest. METHODS: Langendorff-perfused Sprague-Dawley rat hearts were perfused for 20 min with Krebs-Henseleit (K-H) buffer followed by 30 min of crystalloid cardioplegia and 60 min of reperfusion. Control hearts were perfused with Krebs-Henseleit buffer. Acidic buffer post-conditioning hearts were perfused with acidic K-H buffer (pH 6.8) for the first 3 min of reperfusion. Acidic buffer plus cyclosporine A hearts were perfused with K-H acidic buffer (pH 6.8) containing cyclosporine A (0.2 µmol/L) for the first 3 min of reperfusion. RESULTS: Compared with the control group, acidic buffer or plus cyclosporine A post-conditioning significantly improved myocardial performance, decreased cytochrome C release into the cytosol, increased Bcl-2 expression and decreased Bax expression, decreased sensitivity of mPTP-opening to [Ca2+] and the rate of apoptosis after reperfusion. CONCLUSION: These findings suggested that acidic buffer or plus cyclosporine A post-conditioning prevented apoptosis-related mitochondrial permeabilization and provided the myocardial protection after cardioplegic arrest.

Evaluation of shunting flow differences in varied conditions in a simulated adult CPB model during normothermia.

BACKGROUND: It is well documented that lower pump flow during clinical cardiopulmonary bypass (CPB) procedures may be significantly detrimental to tissues and organs. The major cause of hypoperfusion is due to shunting flow existing in the closed CPB circuits. The purpose of this investigation was to evaluate various shunting flow conditions in a simulated adult CPB model under normothermia. MATERIALS AND METHODS: The pseudo adult patient undergoing CPB was established with an extracorporeal circuit. The pre-oxygenator flow, post-filter flow and purge line pressure were recorded. The temperature of the circuit was kept around 36°C using a heat-cooler. The pseudo patient was subjected to five pump flow rates ranging from 3000 to 5000 ml/min (500 ml/min increments), and post-filter pressure was varied from 120-220 mmHg (20 mmHg increments) using a single, static roller pump. Four different shunting states were measured with two flowmeters. RESULTS: When the pump flow was constant, the percentage of shunting flow increased as the post-filter pressure increased in State 1. However, when the post-filter pressure was constant, the trend of the shunting flow was the opposite. Purge line pressure increased with the increase of the post-filter pressure at a constant pump flow rate in State 1. The shunting flow for State 2 was the largest of the four states. The shunting flow for State 3 was similar to State 4. CONCLUSION: During different states of shunt opening, varying degrees of blood flow were diverted away from the arterial line. Shunting of blood flow may, therefore, result in hypoperfusion in the patient.

Perioperative monitoring of thromboelastograph on blood protection and recovery for severely cyanotic patients undergoing complex cardiac surgery.

In this study, we assessed the clinical effect of a new transfusion therapy guided by thromboelastograph (TEG) on blood protection. Thirty-one children with severe cyanosis (hematocrit ≥54%), who were diagnosed as having transposition of the great arteries or double outlet right ventricle with or without pulmonary valve stenosis, and underwent arterial switch operation or double roots transplantation, were involved and were divided into two groups. In group F (n=17), the transfusion therapy after cardiopulmonary bypass was performed with fibrinogen administration combined with traditional transfusion, guided by TEG. In group C (n=14), traditional transfusion guided by clinical experiences only was performed. We observed the blood protection effects and recovery conditions of these patients. In surgery, compared with group C, the chest closure time, fresh-frozen plasma (FFP), and platelet (PLT) volume used at closure time had no significant reductions in group F (P>0.05, respectively), and the patients in group F had no significant reductions in the amount of chest drainage (P>0.05). The total PLT and total red blood cells usage were also the same (P>0.05). But during the first 24h, FFP usage in the intensive care unit (ICU) and total perioperative FFP usage had significantly dropped in group F (P<0.05); the mechanical ventilator time, ICU stay, and hospitalization time in group F were much shorter than those in group C (P<0.05). So, TEG was effective in perioperative blood protection. Fibrinogen could be a substitute for FFP to restore hemostasis and improve the prognosis for these patients.