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.

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.

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.

[Advances in the application of extracorporeal membrane oxygenation in the treatment of severe burn].

Extracorporeal membrane oxygenation (ECMO) is a kind of technique that uses extracorporeal circulation system to draw patients' blood into the circuit, and then oxygenate the blood when it passes along the membrane, followed by returning the blood into patients. At present, ECMO is mainly used in treating patients with respiratory failure and circulatory failure, for whom the conventional treatment such as mechanical ventilation and vasoactive drugs are invalid. ECMO can provide cardiopulmonary support for burn patients with respiratory failure or circulatory failure, and put the heart and lung at rest. The purpose of this paper is to review the application of ECMO in the treatment of severe burn.

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.

[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 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.

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.

Which is the better option during neonatal cardiopulmonary bypass: HTK solution or cold blood cardioplegia?

The optimal myocardial protection strategy for newborns/infants undergoing congenital heart surgery remains controversial. The purpose of this study was to compare myocardial protection using histidine-tryptophan-ketoglutarate (HTK) and cold blood cardioplegia in a neonatal piglet model. Twenty-one piglets were randomized to three groups: the control group (C group, n = 7), a single dose of HTK group (H group, n = 7), and multidose cold blood cardioplegia group (B group, n = 7). Animals in the two experimental groups were placed on hypothermic cardiopulmonary bypass, after which the ascending aorta was clamped for 2 hours. Immediately after declamping, both the difference between arterial and coronary sinus blood lactate concentrations and the oxygen extraction did not differ between the H group and the B group. At 3 hours after declamping, rise in serum troponin-T and creatine kinase isoenzyme MB levels showed no significant differences between the H group and the B group (p = 0.735 and p = 0.103, respectively). No significant differences were noted in the myocardial lactate content, ATP content, and histopathological score between the H group and the B group (p = 0.810, p = 0.158, and p = 0.399, respectively). Transfusion requirement in the B group was significantly more than that in the H group (p = 0.003). HTK solution provides equivalent myocardial protection to multidose cold blood cardioplegia for the neonatal heart with less transfusion requirement.

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.

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.

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.

Hyperoxia management during deep hypothermia for cerebral protection in circulatory arrest rabbit model.

As a brain protection strategy, antegrade selective cerebral perfusion (ASCP) is widely used in thoracic aorta surgery with deep hypothermic circulatory arrest (DHCA), yet the oxygen management for ASCP has never been standardized. The aim of this study was to investigate the possible neuroprotective effects of hyperoxia management during deep hyperthermia for ASCP combined with DHCA in a rabbit model. Rabbits were assigned into four groups: sham group, without cardiopulmonary bypass (CPB); DHCA group, DHCA for 80 minutes; ASCP group, ASCP combined with DHCA; and SH group, hyperoxia management combined with ASCP and DHCA. Hyperoxia management was performed when the nasopharyngeal temperature was below 22°C. Deep hypothermic circulatory arrest was initiated when nasopharyngeal temperature reached 16-18°C. Blood samples were withdrawn to determine blood gas indexes and neurobiochemical markers of damage, and brain tissues were stored for biochemical analysis. Cerebral oxygen balance was performed better in the SH group compared with the DHCA group and the ASCP group. Hyperoxia management did not increase lipid peroxidation with lower malondialdehyde levels in the SH group compared with the DHCA group and the ASCP group (p < 0.05). S100 calcium binding protein B in the SH group was lower compared with the DHCA group and the ASCP group (p < 0.05). There was no significant difference of neuron-specific enolase in the SH group compared with the sham group. Hyperoxia management during deep hypothermia provided substantial dissolved oxygen and demonstrated better cerebral protection over normoxia management.