Start Of Cardiopulmonary Bypass Research Articles

Therapeutic strategy for totally thoracoscopic repeat mitral valve surgery under moderate hypothermia-induced ventricular fibrillation

Objective: To examine the therapeutic strategy and its impacting factors by analyzing the perioperative outcomes of total thoracoscopic repeat mitral valve surgery under moderate hypothermia-induced ventricular fibrillation with cardiopulmonary bypass. Methods: This study is a retrospective case series. Totally 63 patients who underwent repeat mitral valve surgery by the same surgeon from January 2021 to December 2023 in Department of Cardiovascular Surgery, the First Medical Center of People's Liberation Army General Hospital were retrospectively enrolled. There were 28 males and 35 females with an age of (58.3±15.9) years (range: 13 to 84 years). Surgery was performed using a totally thoracoscopic approach under moderate hypothermia-induced ventricular fibrillation. Mitral valvuloplasty was completed in 32 cases and mitral valve replacement in 31 cases. Preoperative baseline data and perioperative outcomes of the patients were collected and Logistic regression was used to analyze independent influencing factors of premature ventricular contractions in the early postoperative period. Results: The intraoperative cardiopulmonary bypass time was (191.5±50.9) minutes (range: 95 to 286 minutes), and the hypothermic ventricular fibrillation time was (99.0±39.8) minutes (range: 34 to 203 minutes). The anal temperature before the start of cardiopulmonary bypass was (36.3±0.5) ℃ (range: 35.2 to 38.0 ℃), the lowest intraoperative anal temperature was (27.3±1.3) ℃(range: 23.7 to 30.1 ℃), and the anal temperature at the time of the cessation of cardiopulmonary bypass was (36.3±0.4) ℃ (range: 35.2 to 37.0 ℃), and excessive rewarming was observed in 33 cases. Six cases applied the artificial heart assist device. Seventeen cases developed premature ventricular contractions in the early postoperative period. Two cases developed neurologic complications. Five cases developed respiratory complications. One case developed urological systemic complications. Six cases were mechanically ventilated for more than 3 days, and the duration of ICU stay in 16 cases was more than 3 days and the postoperative discharge time of (M(IQR)) 8.0 (3.5) days (range: 3 to 26 days). Two cases died or were discharged voluntarily. Logistic regression results showed that persistent preoperative atrial fibrillation (OR=11.424, 95%CI: 1.477 to 144.564, P=0.033) and excessive rewarming (OR=15.249, 95%CI: 1.357 to 279.571, P=0.038) were independent risk factors for the appearance of premature ventricular contractions in the early postoperative period. Conclusions: The technique of total thoracoscopic surgery under induced moderate hypothermic ventricular fibrillation with cardiopulmonary bypass could be applied to repeated mitral valve surgeries with less trauma and faster recovery. Persistent preoperative atrial fibrillation and excessive rewarming are independent risk factors for the occurrence of premature ventricular contractions in the early postoperative period.

Platelet reactivity in young children undergoing congenital heart disease surgery: a NITRIC randomized clinical trial substudy

IntroductionThe international NITRIC trial studied the hypothesis that nitric oxide (NO) applied into the cardiopulmonary bypass (CPB) oxygenator in infants would improve recovery after heart surgery. In a substudy, we evaluated the effect of NO applied into the CPB oxygenator on the (re)activity of platelets measured as fibrinogen binding (platelet aggregation) and P-selectin expression (platelet degranulation) in young children.MethodsPlatelet activity (without agonist exposure) and reactivity (after stimulation by an agonist) was studied in a single center substudy of the NITRIC trial, a multicenter, randomized trial that studied administration of 20 parts per million (ppm) NO during CPB in children younger than 2 years. Blood was collected at 4 time points (T1- T4); before CPB, after CPB start, before and after weaning. Flow cytometry-based platelet activity and reactivity in the presence of 5 agonists was tested. Differences on P-selectin expression and fibrinogen binding (median fluorescence intensity (MFI)) were analyzed with mixed effect modelling (MEM).ResultsBlood samples were obtained in 22 patients allocated to NO and 20 controls. Platelet counts dropped after T1 due to the hemodilution of blood in all patients (p < 0.001). Beta coefficients for NO allocation derived from the MEM models on fibrinogen binding and P-selectin expression were small (standardized beta coefficients on fibrinogen binding were 0.07[0.03, 0.11] and on P-selectin expression 0.05[0.03, 0.08]) and non-significant. CPB duration did not affect platelet reactivity (standardized beta coefficients 0.09[0.02, 0.12] with p > 0.27) in any of the MEMs.Conclusion20 ppm NO administration in the sweep gas of the CPB oxygenator did not affect platelet reactivity in young children undergoing heart surgery. Interestingly, duration of CPB exposure also did not have an effect on platelet (re)activity.Trial registrationANZCTR, ACTRN12617000821392. Registered 5 June 2017, https://anzctr.org.au/

The effect of air-free administration of intravenous drugs on microemboli during cardiopulmonary bypass.

During cardiopulmonary bypass (CPB), gaseous microemboli (GME) that originate from the extracorporeal circuit are released into the arterial blood stream of the patient. Gaseous microemboli may contribute to adverse outcome after cardiac surgery with CPB. Possibly, air may be collected in the right atrium during induction of anesthesia and released during CPB start. The aim of this study was to assess if the GME load entering the venous line of the CPB circuit could be reduced by training of anesthesia personal in avoiding air introduction during administration of intravenous medication. In 94 patients undergoing coronary artery bypass grafting with CPB, GME number and volume were measured intraoperatively with a bubble counter (BCC300). The quantity and the relationship between GME number and volume in the venous and arterial line were determined in 2 periods before and after education of the anesthesiologists and nurses. In the venous line no significant differences were observed between numbers and volumes of GME between groups. Comparing patients with low versus high GME load, showed significantly more patients from the intervention group in the low GME-load group, namely 29 versus 18. Administration of medication by anesthesia was confirmed as a clear cause of GME/air-introduction into the venous circulation. Scavenging properties of the CPB circuit including the oxygenator showed a 99.9% reduction of GME. A wide spread of GME generation during perfusion was present with no difference in generation of GME between groups. Lower GME load observed in patients (intervention group) and examples of air introduction during drug administration suggest that air introduced by anesthesia contributes to the GME load during CPB. Scavenging properties of the CPB circuit contribute very much to patient safety regarding reduction of venous air. Awareness and education create the possibilities for further reduction of GME during cardiopulmonary bypass.

Effects of nitric oxide on microviscosity and polarity of erythrocyte membranes in experiment

Enhancement of methods for protecting target organs during coronary artery bypass surgery determined the development of a technology for delivering nitric oxide (NO) to the systemic blood flow using a cardiopulmonary bypass (CB) apparatus, which makes NO available to all organs and tissues.The aim of the study was to access the effect of perioperative NO conditioning on the coefficients of microviscosity and polarity of sheep etythrocyte membranes during experimental surgical intervention using CB.Material and methods. Study was carried out on 20 sheep weighing 30–34 kg. Two groups were formed. In the CB group, 10 sheep underwent the standard clinical protocol of artificial lung ventilation (ALV) and CB. In the CB + NO group, 10 sheep received NO at a dose of 80 ppm through the circuit of ALV apparatus immediately after tracheal intubation. At the start of CB, NO was delivered to the extracorporeal circulation circuit at a dose of 80 ppm for 90 min. After disconnection from CB, NO supply continued through the ALV apparatus at a dose of 80 ppm for 60 min. The coefficients of microviscosity and polarity of sheep erythrocyte membranes were determined by spectrofluorimetry using pyrene probe.Results and discussion. The implementation of CB was accompanied by a statistically significant decrease in the microviscosity coefficient in the zones of proteinlipid contact of sheep erythrocyte membranes. In the zone of total lipids, the microviscosity coefficient did not change after CB implementation. The membrane polarity coefficient at the final stage of the surgery increased significantly in the zone of annular lipids and did not change in the zone of total lipids. NO supply to the circuit of the extracorporeal circulation neutralizes the revealed increase in the microviscosity and polarity of the annular lipids.Conclusions. The introduction of NO into the extracorporeal circulation circuit at the concentration of 80 ppm prevents a decrease in the coefficients of microviscosity and polarity of annular lipids of erythrocyte membranes that occurs during cardiac surgery.

Urinary Collectrin as Promising Biomarker for Acute Kidney Injury in Patients Undergoing Cardiac Surgery.

Early detection of acute kidney injury (AKI) is crucial for timely intervention and improved patient outcomes after cardiac surgery. This study aimed to evaluate the potential of urinary collectrin as a novel biomarker for AKI in this patient population. In this prospective, observational cohort study, 63 patients undergoing elective cardiac surgery with cardiopulmonary bypass (CPB) were studied at the Medical University of Vienna between 2016 and 2018. We collected urine samples prospectively at four perioperative time points, and urinary collectrin was measured using an enzyme-linked immunosorbent assay. Patients were divided into two groups, AKI and non-AKI, defined by Kidney Disease: Improving Global Outcomes Guidelines, and differences between groups were analyzed. Postoperative AKI was found in 19 (30%) patients. Urine sample analysis revealed an inverse correlation between urinary collectrin and creatinine and AKI stages, as well as significant changes in collectrin levels during the perioperative course. Baseline collectrin levels were 5050 ± 3294 pg/mL, decreased after the start of CPB, reached their nadir at the end of surgery, and began to recover slightly on postoperative day (POD) 1. The most effective timepoint for distinguishing between AKI and non-AKI patients based on collectrin levels was POD 1, with collectrin levels of 2190 ± 3728 pg/mL in AKI patients and 3768 ± 3435 pg/mL in non-AKI patients (p = 0.01). Urinary collectrin shows promise as a novel biomarker for the early detection of AKI in patients undergoing cardiac surgery on CPB. Its dynamic changes throughout the perioperative period, especially on POD 1, provide valuable insights for timely diagnosis and intervention. Further research and validation studies are needed to confirm its clinical usefulness and potential impact on patient outcomes.

Minimal invasive extracorporeal circulation in comorbid patients

Background: As the severity of comorbid diseases increases, risks of cardiopulmonary bypass (CPB) complications significantly increase. A complex of the procedure’s damaging factors provokes a systemic inflammatory response that in some cases is accompanied by the damage to target organs, transitioning from chronic organ dysfunctions into acute ones. Some studies on the use of minimal invasive extracorporeal circulation (MiECC) systems show their advantage over conventional extracorporeal circulation (CECC); however, the diversity of MiECC systems, patients, and outcomes precludes us from confidently extrapolating these data to older comorbid patients.Objective: To compare the severity of systemic inflammation and treatment outcomes in comorbid patients who underwent cardiac surgery with CECC and MiECC.Methods: We conducted a retrospective cohort study of 760 patients who consecutively underwent elective cardiac operations in 2019-2022. Inclusion criteria: comorbid status (age-adjusted Charlson Comorbidity Index score of ≥6); CPB time ≥90 min. Exclusion criteria: emergency surgery, refusal to participate in the study. A total of 68 patients met the inclusion criteria. We formed 2 study groups based on the extracorporeal circulation method: CECC group (n = 51) and MiECC group (n = 17). Control points: before CPB and 24 hours after the surgery (lactate; creatinine; oxygenation index, hemolysis level). For systemic inflammatory response markers: 1 hour after the CPB start and 24 hours after the CPB end (interleukin 6; interleukin 10; procalcitonin; C-reactive protein; soluble Triggering Receptor Expressed on Myeloid Cells-1 [sTREM-1]). We evaluated respiratory and renal complications, drainage-related hemorrhages, hemostatic disorders, the need for sympathomimetic drugs, and the length of stay in an intensive care unit and inpatient hospital.Results: Between the groups there were no statistically significant differences in gender and anthropometric characteristics, surgery types, and main perfusion parameters. In the CECC group, we observed significantly higher doses of vasoconstrictors (norepinephrine) as well as a decrease in urine output and lung injury and an increase in lactate and hemolysis. The systemic inflammatory response markers were also significantly higher.Conclusion: Compared with CECC, MiECC does not significantly affect the frequency of organ dysfunctions; however, it reduces the severity of the systemic inflammatory response and immune suppression that are trigger mechanisms for multiple organ dysfunction syndrome. It is particularly important for patients with chronic organ dysfunctions. A range of indications for MiECC systems should be defined given its high cost and off-target effect on pleiotropic factors of systemic inflammatory response development. Received 6 April 2023. Revised 17 August 2023. Accepted 18 August 2023. Funding: The study was conducted within the framework of the research project "Development of minimally invasive and hybrid technologies for surgical treatment of heart diseases". Conflict of interest: The authors declare no conflict of interest. Contribution of the authorsConception and study design: A.Sh. Revishvili, G.P. Plotnikov, V.A. PopovData collection and analysis: R.A. Kornelyuk, L.B. Berikashvili, I.P. Komkov, E.S. Malyshenko, V.M. ZemskovStatistical analysis: L.B. BerikashviliDrafting the article: R.A. Kornelyuk, G.P. Plotnikov, L.B. Berikashvili Critical revision of the article: G.P. PlotnikovFinal approval of the version to be published: A.Sh. Revishvili, R.A. Kornelyuk, G.P. Plotnikov, L.B. Berikashvili, I.P. Komkov, E.S. Malyshenko, V.M. Zemskov, V.A. Popov

Effect of cardiopulmonary bypass on plasma and erythrocytes oxylipins

BackgroundOxylipins, the oxidative metabolites of polyunsaturated fatty acids (PUFAs), serve as key mediators of oxidative stress, inflammatory responses, and vasoactive reactions in vivo. Our previous work has established that hemodialysis affects both long chain fatty acids (LCFAs) and oxylipins in plasma and erythrocytes to varying degrees, which may be responsible for excess cardiovascular complications in end-stage renal disease. In this study, we aimed to determine changes in blood oxylipins during cardiopulmonary bypass (CPB) in patients undergoing cardiac surgery to identify novel biomarkers and potential metabolites of CPB-related complications. We tested the hypothesis that CPB would differentially affect plasma oxylipins and erythrocytes oxylipins.MethodsWe conducted a prospective observational study of 12 patients undergoing elective cardiac surgery with expected CPB procedure. We collected venous and arterial blood samples before CPB, 15 and 45 min after the start of CPB, and 60 min after the end of CPB, respectively. Oxylipins profiling in plasma and erythrocytes was achieved using targeted HPLC‐MS mass spectrometry.ResultsOur results revealed that most venous plasma diols and hydroxy- oxylipins decreased after CPB initiation, with a continuous decline until the termination of CPB. Nevertheless, no statistically significant alterations were detected in erythrocytes oxylipins at all time points.ConclusionsCPB decreases numerous diols and hydroxy oxylipins in blood plasma, whereas no changes in erythrocytes oxylipins are observed during this procedure in patients undergoing cardiac surgery. As lipid mediators primarily responsive to CPB, plasma diols and hydroxy oxylipins may serve as potential key biomarkers for CPB-related complications.

Accuracy of Cardiac Output Measured by Fourth-Generation FloTrac and LiDCOrapid, and Their Characteristics Regarding Systemic Vascular Resistance in Patients Undergoing Cardiac Surgery

The clinical use of less-invasive devices that calculate the cardiac output from arterial pressure waveform is increasing. The authors aimed to evaluate the accuracy and characteristics of the systemic vascular resistance index (SVRI) of the cardiac index measured by 2 less-invasive devices, fourth-generation FloTrac (CIFT) and LiDCOrapid (CILR), compared with the intermittent thermodilution technique, using a pulmonary artery catheter (CITD). This was a prospective observational study. This study was conducted at a single university hospital. Twenty-nine adult patients undergoing elective cardiac surgery. Elective cardiac surgery was used as an intervention. Hemodynamic parameters, CIFT, CILR, and CITD, were measured after the induction of general anesthesia, at the start of cardiopulmonary bypass, after completion of weaning from cardiopulmonary bypass, 30 minutes after weaning, and at sternal closure (135 measurements in total). The CIFT and CILR had moderate correlations with CITD (r=0.62 and 0.58, respectively). Compared with CITD, CIFT, and CILR had a bias of -0.73 and -0.61 L/min/m2, limit of agreement of -2.14-to-0.68 L/min/m2 and -2.42-to-1.20 L/min/m2, and percentage error of 39.9% and 51.2%, respectively. Subgroup analysis for evaluating SVRI characteristics showed that the percentage errors of CIFT and CILR were 33.9% and 54.5% in low SVRI (<1,200 dyne×s/cm5/m), 37.6% and 47.9% in moderate SVRI (1,200-1,800 dyne×s/cm5/m), 49.3% and 50.6% in high SVRI (>1,800 dyne·s/cm5/m2), respectively. The accuracy of CIFT or CILR was not clinically acceptable for cardiac surgery. Fourth-generation FloTrac was unreliable in high SVRI. LiDCOrapid was inaccurate across a broad range of SVRI, and minimally affected by SVRI.

Time course changes in insulin sensitivity during cardiac surgery: A retrospective study on intraoperative glycemic management using an artificial pancreas.

Glycemic control is essential for improving the prognosis of cardiac surgery, although precise recommendations have not yet been established. Under a constant blood glucose level, the insulin infusion rate correlates with insulin resistance during glycemic control using an artificial pancreas (AP). We conducted this retrospective study to elucidate changes in intraoperative insulin sensitivity as a first step to creating glycemic control guidelines. Fifty-five cardiac surgery patients at our hospital who underwent intraoperative glycemic control using an AP were enrolled. Twenty-three patients undergoing surgical procedures requiring cardiac arrest under hypothermic cardiopulmonary bypass (CPB) with minimum rectal temperatures lower than 32°C, 13 patients undergoing surgical procedures requiring cardiac arrest under hypothermic CPB with minimum rectal temperatures of 32°C, eight patients undergoing on-pump beating coronary artery bypass grafting and 11 patients undergoing off-pump coronary artery bypass were assigned to groups A, B, C and D, respectively. We analyzed the time course of changes in the data derived from glycemic control using the AP. Significant time course changes were observed in groups A and B, but not in groups C and D. Insulin resistance was induced after the start of hypothermic CPB in groups A and B, and the induced change was not resolved by the rewarming procedure, remaining sustained until the end of surgery. Hypothermia is the predominant factor of the induced insulin resistance during cardiac surgery. Thus, careful glycemic management during hypothermic CPB is important. Prospective clinical studies are required to confirm the findings of this study.

Metalloproteinases in Cardiac Surgery: A Systematic Review

The role of matrix metalloproteinases (MMPs) in routine cardiac operations including cardiopulmonary bypass (CPB) is still poorly explored. The purpose of this systematic review was to thoroughly summarize and discuss the existing knowledge of the MMP profile in cardiac surgery. All studies meeting the inclusion criteria (i.e., those reporting detailed data about MMP release during and after CPB) were selected after screening the literature published between July 1975 and August 2022. Fifteen trials that enrolled a total of 431 participants were included. MMP levels were found to be significantly correlated with CPB in all included studies. The gelatinases MMP-2 and MMP-9 were highly released in cardiac surgery with CPB. MMP-9 levels were found to be increased after CPB start and during the duration of CPB. Particularly, it is overexpressed both in the myocardial tissue and circulating in the bloodstream. Also, MMP-2 levels increased after CPB both in plasma and in myocardial tissue. MMP-7, MMP-8, and MMP-13 levels increased after CPB start and remained elevated up to 6 h later. Increased levels of MMPs were associated with adverse post-operative outcomes. Conversely, TIMP-1 decreased with CPB. Mechanical and pharmacological strategies were applied in two studies to analyze their effect on the inflammatory response to cardiac surgery and CPB and on postoperative outcomes. New targeted MMP inhibitor therapies could protect against systemic inflammatory response syndrome after CPB and should be the subject of future large prospective multicenter randomized clinical trials.

Multimodal measurement of glycocalyx degradation during coronary artery bypass grafting.

Glycocalyx shedding and subsequent endothelial dysfunction occur in many conditions, such as in sepsis, in critical illness, and during major surgery such as in coronary artery bypass grafting (CABG) where it has been shown to associate with organ dysfunction. Hitherto, there is no consensus about the golden standard in measuring glycocalyx properties in humans. The objective of this study was to compare different indices of glycocalyx shedding and dysfunction. To this end, we studied patients undergoing elective CABG surgery, which is a known cause of glycocalyx shedding. Sublingual glycocalyx thickness was measured in 23 patients by: 1) determining the perfused boundary region (PBR)-an inverse measure of glycocalyx thickness-by means of sidestream dark field imaging technique. This is stated double, 2) measuring plasma levels of the glycocalyx shedding products syndecan-1, hyaluronan, and heparan sulfate and 3) measuring plasma markers of impaired glycocalyx function and endothelial activation (Ang-2, Tie-2, E-selectin, and thrombomodulin). Measurements were performed directly after induction, directly after onset of cardiopulmonary bypass (CPB), and directly after cessation of CPB. We assessed changes over time as well as correlations between the various markers. The PBR increased from 1.81 ± 0.21 μm after induction of anesthesia to 2.27 ± 0.25 μm (p < 0.0001) directly after CPB was initiated and did not change further during CPB. A similar pattern was seen for syndecan-1, hyaluronan, heparan sulfate, Ang-2, Tie-2, and thrombomodulin. E-selectin levels also increased between induction and the start of CPB and increased further during CPB. The PBR correlated moderately with heparan sulfate, E-selectin, and thrombomodulin and weakly with Syndecan-1, hyaluronan, and Tie-2. Shedding markers syndecan-1 and hyaluronan correlated with all functional markers. Shedding marker heparan sulfate only correlated with Tie-2, thrombomodulin, and E-selectin. Thrombomodulin correlated with all shedding markers. Our results show that glycocalyx thinning, illustrated by increased sublingual PBR and increased levels of shedding markers, is paralleled with impaired glycocalyx function and increased endothelial activation in CABG surgery with CPB. As correlations between different markers were limited, no single marker could be identified to represent the glycocalyx in its full complexity.

Significant adhesion reduction and time saving in pediatric heart surgery with 4DryField PH: A retrospective, controlled study.

Adhesions formation after surgery for congenital heart defects can complicate follow-up procedures due to bleeding from detached adhesion bands, injury to cardiac structures or large vessels, all of which do prolong operation times. The problem is enhanced by the fact that detached adhesions are predilection sites for new adhesions setting off a downward spiral. 4DryField® PH gel barrier has demonstrated high efficacy in reducing postoperative adhesions in general surgical and gynecological studies. This retrospective controlled study of 22 patients evaluates whether these positive results can be confirmed in pediatric cardiac surgery. Adhesions were scored from photographs of follow-up interventions by an independent cardiac surgeon blinded to group assignment. The publication provides not only score numbers but also original photographs of all sites for better traceability and transparency. In addition, timesaving due to reduced adhesions was evaluated. Results show a significantly reduced adhesion score for the 4DryField® group. Importantly, this resulted in a significantly shorter period between skin incision and start of cardiopulmonary bypass. In addition, timesaving due reduced adhesion formation was evaluated. The use of 4DryField® was safe, although higher doses per kg were used than in adults.

A comparison of the ClotPro system with rotational thromboelastometry in cardiac surgery: a prospective observational study

Viscoelastic coagulation tests have been increasingly used for hemostasis management in cardiac surgery. The ClotPro system is a novel viscoelastic device based on principles of rotational thromboelastometry. We aimed to compare ClotPro with ROTEM and plasma coagulation assays in cardiopulmonary bypass (CPB) patients. Blood samples were collected from 25 CPB patients at (1) baseline, (2) start of CPB, (3) end of CPB, and (4) end of surgery. The EX-test, IN-test, HI-test, FIB-test parameters on ClotPro were compared with corresponding ROTEM assay (EXTEM, INTEM, HEPTEM, and FIBTEM). Standard plasma coagulation assays and endogenous thrombin generation (TG) were simultaneously evaluated. Pearson correlation analyses showed moderate correlations between clotting times (CTs) (r = 0.63–0.67; p < 0.001, respectively), and strong correlations with maximal clot firmness (MCF) (r = 0.93–0.98; p < 0.001, respectively) between ClotPro and ROTEM. EX-test and IN-test MCF parameters were interchangeable with acceptable percentage errors (EX-test MCF: 7.3%, IN-test MCF: 8.3%), but FIB-test MCF (27.0%) and CT results were not (EX-test CT: 44.7%, IN-test CT: 31.4%). The correlations of PT/INR or peak TG with EX-test CTs were higher than with EXTEM CTs (PT/INR: r = 0.80 and 0.41, peak TG: 0.43 and 0.18, respectively). FIB-test MCF has strong correlation with plasma fibrinogen and factor XIII level (r = 0.84 and 0.66, respectively). ROC analyses showed that ClotPro was capable of emulating well-established ROTEM thresholds (area under curves: 0.83–1.00). ClotPro demonstrated strong correlations in MCF parameters of ROTEM in CPB patients. It may be reasonable to modify ROTEM-based transfusion algorithm pertaining to MCF parameters to establish cut-off values for ClotPro device.

Molecular hydrogen exposure improves functional state of red blood cells in the early postoperative period: a randomized clinical study.

Molecular hydrogen (H2) has been considered a preventive and therapeutic medical gas in numerous diseases. The study aimed to investigate the potential role of molecular hydrogen as a component of anesthesia in surgical treatment with cardiopulmonary bypass (CPB) of acquired valve defects on the functional state of red blood cells (RBC) and functional indicators of cardiac activity. This clinical trial was conducted with 20 patients referring to the Specialized Cardiosurgical Clinical Hospital, Nizhny Novgorod, Russian Federation, who underwent elective surgery with CPB. Twenty-four patients were randomly assigned to two groups. First group included 12 patients (research group) who received H2 at a concentration of 1.5–2.0% through a facemask using a breathing circuit of the ventilator together with anesthesia immediately after tracheal intubation and throughout the operation. Second group (control group) included 12 patients who were not given H2. Blood samples were withdrawn from peripheral veins and radial artery at four stages: immediately after the introduction of anesthesia (stage 1), before the start of CPB (stage 2), immediately after its termination (stage 3) and 24 hours after the operation (the early postoperative period) (stage 4). An increase in electrophoretic mobility, an increase in the metabolism of red blood cells, and a decrease in the aggregation of red blood cells relative to the corresponding indicators of the control group were observed in the research group. Patients in the research group had a decrease in oxidative stress manifestations most pronounced one day after the operation. There was a statistically significant difference between the indicators of myocardial contractile function in the research and control group on the 1st and 3rd days after surgery. H2 inhalation leads to improvement of functional state of red blood cells, which is accompanied by a more favorable course of the early postoperative period. These data show the presence of protective properties of molecular hydrogen.

Alpha-2-adrenergic receptor agonists for the prevention of delirium and cognitive decline after open heart surgery (ALPHA2PREVENT): protocol for a multicentre randomised controlled trial

IntroductionPostoperative delirium is common in older cardiac surgery patients and associated with negative short-term and long-term outcomes. The alpha-2-adrenergic receptor agonist dexmedetomidine shows promise as prophylaxis and treatment for delirium...

ДИНАМИКА УРОВНЯ КОРТИЗОЛА КРОВИ ПРИ КАРДИОХИРУРГИЧЕСКИХ ВМЕШАТЕЛЬСТВАХ В УСЛОВИЯХ ОБЩЕЙ МНОГОКОМПОНЕНТНОЙ СБАЛАНСИРОВАННОЙ АНЕСТЕЗИИ

Objectives. The severity of the stress hormonal response during operations on heart valves in cardiopulmonary bypass (CPB) in multicomponent general anesthesia (GA) was evaluated by determining the level of plasma cortisol at different stages of the operation. Material and methods. Cortisol levels were studied in 24 patients who had undergone heart valve surgery in CPB. Results. At the stage 10 minutes before the start of the IC, cortisol levels were in the range of physiological values, at the end of the surgical intervention, cortisol increased by 3.3 (3.0; 5.2) times, compared with preoperative period. Conclusion. The level of plasma cortisol equal to 586.2 (410.7; 733.0) nmol/l at the patient's admission to the operating room, 426.3 (299.3; 597.0) nmol/l 10 minutes before the start of CPB, with its increase to 2170.6 (2077.0; 2427.2) nmol/l at the end of the operation, is the stress norm during operations on heart valves in GA.

The equilibrated blood sevoflurane concentrations show a rapid decrease after switching from ventilation for the human lung to cardiopulmonary bypass.

ABSTRACTVolatile anesthetics (VAs) protect myocardial cells during cardiovascular surgeries, including cardiopulmonary bypass (CPB). In CPB, blood is gradually transferred from the body to a CPB unit until the target cardiac index is achieved, following which human lung (HL) ventilation is stopped. This pilot study aimed to evaluate changes in the blood sevoflurane concentrations 5 min after the start of CPB when its delivery to the oxygenator began after HL ventilation with sevoflurane was completed. Six patients were recruited and participated in this study. For each patient, the equilibrated blood sample, collected 20 min after starting the delivery of 1.7% sevoflurane (HL group), and another blood sample, collected 5 min after starting the CPB, were analyzed using gas chromatography equipped with a flame ionization detector. The mean (± standard deviation) sevoflurane concentrations in the HL and 5 min after starting CPB groups were 58.6 ± 4.7 and 14.5 ± 5.0 μg/ml, respectively (P < 0.01). In conclusion, the equilibrated blood sevoflurane concentrations showed a rapid decrease when switching from sevoflurane ventilation for the HL to CPB unless it was introduced to the oxygenator until completion of the switch.

The effect of selective cerebral perfusion on cerebral versus somatic tissue oxygenation during aortic coarctation repair in neonates and infants

BackgroundSuboptimal tissue perfusion and oxygenation may be the root cause of certain perioperative complications in neonates and infants having complicated aortic coarctation repair. Practical, effective, and real-time monitoring of organ perfusion and/or tissue oxygenation may provide early warning of end-organ mal-perfusion.Methods Neonates/infants who were scheduled for aortic coarctation repair with cardiopulmonary bypass (CPB) and selective cerebral perfusion (SCP) from January 2015 to February 2017 in Children’s Hospital of Nanjing Medical University participated in this prospective observational study. Cerebral and somatic tissue oxygen saturation (SctO2 and SstO2) were monitored on the forehead and at the thoracolumbar paraspinal region, respectively. SctO2 and SstO2 were recorded at different time points (baseline, skin incision, CPB start, SCP start, SCP end, aortic opening, CPB end, and surgery end). SctO2 and SstO2 were correlated with mean arterial pressure (MAP) and partial pressure of arterial blood carbon dioxide (PaCO2).ResultsData of 21 patients were analyzed (age=75±67 days, body weight=4.4±1.0 kg). SstO2 was significantly lower than SctO2 before aortic opening and significantly higher than SctO2 after aortic opening. SstO2 correlated with leg MAP when the measurements during SCP were (r=0.67, p<0.0001) and were not included (r=0.46, p<0.0001); in contrast, SctO2 correlated with arm MAP only when the measurements during SCP were excluded (r=0.14, p=0.08 vs. r=0.66, p<0.0001). SCP also confounded SctO2/SstO2’s correlation with PaCO2; when the measurements during SCP were excluded, SctO2 positively correlated with PaCO2 (r=0.65, p<0.0001), while SstO2 negatively correlated with PaCO2 (r=-0.53, p<0.0001).Conclusions SctO2 and SstO2 have distinct patterns of changes before and after aortic opening during neonate/infant aortic coarctation repair. SctO2/SstO2’s correlations with MAP and PaCO2 are confounded by SCP. The outcome impact of combined SctO2/SstO2 monitoring remains to be studied.

Vancomycin concentrations during cardiopulmonary bypass in pediatric cardiac surgery: a prospective study.

Few data are available regarding intraoperative plasma concentrations of vancomycin administered as prophylaxis in pediatric cardiac surgery. The aims of this study were to investigate during pediatric cardiac surgery with cardiopulmonary bypass(CPB) the attainment of the area-under-the-curve of the vancomycin serum concentrations versus time over surgery to minimum inhibitory concentration ratio(AUCintra/MIC) of 400 (mg × h)/l and/or a target concentration of 15-20 mg/l. In a prospective study, 40 patients divided into four subgroups (neonates, infants, children <10 years-old, ⩾10 years-old) undergoing cardiac surgery with cardiopulmonary bypass (CPB) were enrolled. A slow vancomycin bolus of 20 mg/kg, up to a maximum dose of 1000 mg was administered before skin incision and a further dose of 10 mg/kg (up to 500 mg) at CPB start. Vancomycin samples were collected intraoperatively at four time points. The median (interquartile range) age was 241.5 days (47-3898) and the median weight was 7.1 kg (3.1-37). The median AUCintra/MIC was 254.73 (165.89-508.06). In 11 patients the AUCintra/MIC target was not reached. Neonates displayed the lowest AUCintra/MIC values, and these were significantly lower than those of children ⩾10 years old (p = 0.02). Vancomycin concentrations were above the maximal target of 20 mg/l in 82.5% and 80% of patients at surgery and CPB start, respectively. At CPB and surgery end, 42.5% of patients showed vancomycin concentrations above 20 mg/l and 42.5% below 15 mg/l. Patients⩾10 years old showed the highest peak values whereas neonates were those with the lowest troughs. AUCintra/MIC correlated with age(r:0.36, p = 0.02), weight(r:0.35, p = 0.03), intraoperative protein value(r:0.40, p = 0.01), CPB priming volume/kg(r:-0.33, p = 0.04), CPB duration(r:0.36, p = 0.02) and vancomycin troughs(r:0.35, p = 0.04). An AUCintra/MIC ⩾400 target was not reached in one-quarter of children undergoing heart surgery. Vancomycin peaked before the start of surgery and neonates were those with the lowest troughs. Vancomycin concentrations are affected by CPB hemodilution and by patients' age and weight.

Levosimendan Versus Milrinone and Release of Myocardial Biomarkers After Pediatric Cardiac Surgery: Post Hoc Analysis of Clinical Trial Data.

We compared the effect of two inodilators, levosimendan and milrinone, on the plasma levels of myocardial injury biomarkers, that is, high-sensitivity troponin T and heart-type fatty acid binding protein, and on N-terminal prohormone of brain natriuretic peptide as a biomarker of ventricular function. We hypothesized that levosimendan could attenuate the degree of myocardial injury when compared with milrinone. A post hoc, nonprespecified exploratory secondary analysis of the Milrinone versus Levosimendan-1 trial (ClinicalTrials.gov Identifier: NCT02232399). Two pediatric tertiary university hospitals. Infants 1-12 months old, diagnosed with ventricular septal defect, complete atrioventricular septal defect, or Tetralogy of Fallot undergoing corrective surgery with cardiopulmonary bypass. Seventy patients received a loading dose of either levosimendan or milrinone at the start of cardiopulmonary bypass followed by an infusion of the respective drug, which continued for 26 hours. Plasma levels of the three cardiac biomarkers were measured prior to the initiation of cardiopulmonary bypass and 2, 6, and 24 hours after weaning from cardiopulmonary bypass. In both groups, the levels of high-sensitivity troponin T and heart-type fatty acid binding protein were highest at 2 hours post cardiopulmonary bypass, whereas the highest level of N-terminal prohormone of brain natriuretic peptide occurred at 24 hours post cardiopulmonary bypass. There was no significant difference in the biomarkers' plasma levels between the study groups over time. Neither was there a significant difference in the postoperative peak plasma levels of the cardiac biomarkers. In this post hoc analysis of the MiLe-1 trial, there was no demonstrable difference in the postoperative cardiac biomarker profile of myocardial injury and ventricular function when comparing infants managed in the perioperative period with levosimendan versus milrinone.