Abstract: There is a 1% - 4% incidence of cardiac disease in pregnancy, and rheumatic heart disease is the most common diagnosis. On the condition that medical treatment is inefficacious, an open heart surgery should be performed. Because of the changes in physiological functions, there is a major difference between pregnant patients and the general population in perioperative management of valve replacement. Now , the pregnancy is not an absolute contraindication for cardiopulmonary bypass, though the incidence of mortality and birth defects remains high. It is helpful in decreasing complications and increasing survival rate by improving themethods of cardiopulmonary bypass, postoperative monitoring, anticoagulation etc. In this article, the progress in t reatments of perioperative period of cardiac valve replacement during pregnancy is reviewed.
Post operational recovery from cardiac surgery can be affected by many factors, including preoperative, intraoperative, and postoperative factors. Prolonged mechanical ventilation (PMV) , one of the major complications, has been widely accepted as a measure to evaluate the performance and outcomes of cardiac surgeries. Great progress has been made in the studies of risk factors contributing to PMV following cardiac surgeries in recent years. However, no clear and effective measures and approaches are available yet to prevent PMV. In this review, the authors try to summarize the risk factors that are associated with PMV throughout the perioperative period of cardiac surgery, as well as possible interventions when applicable.
Although great progress has been achieved in the techniques and materials of cardiopulmonary bypass (CPB), cardiac surgery under CPB is still one of the surgeries with the highest complication rate. The systemic inflammatory response is an important cause of complications, mainly characterized by activation of innate immune cells and platelets, and up-regulation of inflammatory cytokines. After activation, a variety of molecules on the membrane surface are up-regulated or down-regulated, which can amplify tissue inflammatory damage by releasing cytoplasmic protease and reactive oxygen species, and activate multiple inflammatory signaling pathways in the cell, ultimately leading to organ dysfunction. Therefore, the expression of these cell membrane activation markers is not only a marker of cell activation, but also plays an important role in the process of vital organ injury after surgery. Identification of these specific activation markers is of great significance to elucidate the mechanisms related to organ injury and to find new prevention and treatment methods. This article will review the relationship between these activated biomarkers in the innate immune cells and vital organ injuries under CPB.
ObjectiveTo establish a novel animal model of deep hypothermic circulatory arrest (DHCT) in rabbits without thoracotomy, and investigate acute kidney injury (AKI) induced by DHCT and early novel biomarkers of AKI. MethodsForty-two New Zealand big ear rabbits (3.5-4.0 kg, male or female) were randomly divided into 2 groups with 21 rabbits in each group. Cardiopulmonary bypass (CPB) was established via the right carotid artery and jugular vein in both groups. In Group A, CPB continued when the rectal temperature was maintained at 28℃. In group B, DHCT started when the rectal temperature reached 16℃ to 18℃ and lasted for 60 minutes before CPB was resumed and rewarming was started. The rectal temperature was restored to 35℃ within 30 minutes, then CPB was maintained for 30 minutes. CPB time was same in both groups. Preoperatively and 6 hours, 24 hours and 48 hours after the operation, venous blood samples were taken to examine serum creatinine (Cr) and β-trace protein (β-TP), and urine samples were taken to examine neutrophil gelatinase-associated lipocalin (NGAL). Four rabbits were sacrificed at respective above time points to measure renal malondialdehyde (MDA) content. Hematoxylin-Eosin (HE) staining, TUNEL assay and transmission electron microscopy were used to examine morphological changes of renal tubular epithelial cells (TECs). ResultsFour rabbits died in group A and five rabbits died in Group B during the experiment.(1)Blood Cr:There was no statistical difference between different time points in Group A (P > 0.05). In Group B, serum Cr at 24 hours after the operation was significantly higher than other time points, and also significantly higher than that of group A (P < 0.05).(2)Blood β-TP and urinary NGAL:There was no statistical difference between different time points in Group A (P > 0.05). In Group B, blood β-TP and urinary NGAL at the time of 6 hours, 24 hours and 48 hours postoperatively were significantly higher than preoperative levels (P < 0.05). Blood β-TP and urinary NGAL at the time of 24 hours postoperatively were significantly higher than other time points (P < 0.05). Blood β-TP and urinary NGAL at the time of 6 hours, 24 hours and 48 hours postoperatively were significantly higher than those of group A (P < 0.05).(3)Renal MDA content of Group B at the time of 24 hours postoperatively was significantly higher than other time points as well as that of Group A (P < 0.05).(4) HE staining showed serious pathological injuries of renal TECs at the time of 24 hours postoperatively in Group B. There was no significant pathological injury of renal TECs at the time of 24 hours postoperatively in Group A. (5)TUNEL-positive rate of group B at the time of 24 hours postoperatively was significantly higher than other time points as well as that of group A (P < 0.05).(6)Transmission electron microscope showed serious pathological injuries of renal TECs organelles at the time of 24 hours postoperatively in Group B. There was no significant pathological injury of renal TECs organelles in Group A. ConclusionsThis DHCT rabbit model without thoracotomy is a simple, convenient, and economical animal model with long-term animal survival for the study of DHCT-induced organ injury. AKI is most serious at the time of 24 hours after DHCA. Blood β-TP and urinary NGAL can be used as early biomarkers of DHCT-induced AKI.
Objective To compare the perfusion pressure between cardiopulmonary bypass (CPB) through improved intubations of femoral artery-vein and routine identical flow on organic perfusion such as brain, lung, liver, kidney, intestines, etc.. Methods Twenty dogs with body weight from 10-15kg were randomly divided into two groups: thoracoscope group(n=10): CPB was set up by the right femoral artery-vein for completely video assisted cardiac operations; routine thoracotomy group(n=10): CPB was set up by the aorta-caval vein. The perfusion pressure of innominate artery, left common carotid artery, superior mesenteric artery, renal artery, homonymic and opposite side popliteal artery and the pressure of concomitant vein were measured at the following time points: instantly after induction of anesthesia (T1) , before aortic clamping (T2) , fifteen minutes after aortic clamping (T3) , fifteen minutes after aortic opening (T4) , twenty minutes after stop (T5) . The venous blood samples were collected at the preceding time points and venous oxygen saturation (SvO2) were measured. Results There were no significant difference between both groups in arterial perfusion pressure, besides perfusion pressure of homonymic popliteal artery in thoracoscope group was lower than that in routine thoracotomy group (Plt;0. 01) . Before aortic clamping, fifteen minutes after aortic clamping and fifteen minutes after aortic opening, venous pressure of renal vein, superior mesenteric vein, homonymic and opposite side popliteal vein in thoracoscope group were higher than those in routine thoracotomy group (Plt;0. 05) . SvO2 of renal vein, superior mesenteric vein, homonymic and opposite side popliteal vein in thoracoscope group were lower than those in routine thoracotomy group (Plt;0. 05) . Conclusion The improved femoral CPB has a similar perfusion pressure with routine CPB and a higher vein pressure than routine CPB below inferior vena cava after aortic intubations. So this experiment provides theoretical evidence for the organic protection of infants’ thoracoscopic extracorporeal circulation.
Systemic inflammatory response (SIR) evoked by cardiopulmonary bypass (CPB) is still one of the major causes of postoperative multiple organs injuries. Since the concentrations of circulating inflammatory factors are positively associated with postoperative adverse events, removal or inhibition of inflammatory factors are considered as effective treatments to improve outcomes. After more than 20 years of research, however, the results are disappointed as neither neutralization nor removal of circulating inflammatory factors could reduce adverse events. Therefore, the role of circulating inflammatory factors in CPB-related organs injuries should be reconsidered in order to find effective therapies. Here we reviewed the association between circulating inflammatory factors and the outcomes, as well as the current therapies, including antibody and hemadsorption. Most importantly, the role of circulating inflammatory factors in SIR was reviewed, which may be helpful to develop new measures to prevent and treat CPB-related organs injuries.
Objective To determine the application values of gene chip technique in cardiovascular surgical clinical and research work. Microarray for gene expression profiles was used to screen out the differentially expressed genes during cardiopulmonary bypass(CPB) in peripheral blood mononuclear cell. By doing these, it was hoped that some clues in inflammatory response during CPB could be found out. Methods The patients’ oxygenated bloods were drawn immediately before onset and termination of CPB. Peripheral blood mononuclear cell (PBMC) were obtained from heparinised blood by Ficoll gradient centrifugation. The differentially expression was measured using BD AtlasTM cDNA Expression Arrays. The candidate genes were corroborated by semiquantitative reverse transcriptionpolymerase chain reaction (RT-PCR). Results Gene chip technique was successfully used in CPB study. The gene expression profiles of cytokines of PBMC during CPB were screened out. Interleukin 6 and Wnt5a were the differentially expressed genes. But the validity using semiquantitative RT-PCR found no statistically difference(P=0.888,0.135). Conclusion Microarray technique has positive application values in the study of cytokines during CPB. cDNA microarray for gene expression profiles can primarily screen out differentially expression genes during CPB. These genes may be engaged in inflammation and other pathophysiological reactions during CPB. PBMC is not the major source of cytokines during CPB.
Objective To investigate the effect of new type ultrafiltration technique in preventing and relieving the main organ injury that may follow open heart surgery with cardiopulmonary bypass (CPB),and improve the operative effects and decrease the postoperative complications. Methods Thirty patients with congenital heart diseases were randomly divided into two groups. Modified ultrafiltration group: modified ultrafiltration was used after CPB; new type ultrafiltration group: new type ultrafiltration technique was used throughout CPB. The serum concentrations of nflammatory mediators,hematocrit,serum albumin concentrations, pulmonary function, operative duration time and main organ function parameters were measured in both groups. Results Ultrafiltration time after CPB in new type ultrafiltration group was significantly shorted as compared with modified ultrafiltration group(6.35±1.28 min vs. 12.45±4.52 min,P=0.000); serum concentrations of interleukin6(IL-6)and tumor necrosis factor α(TNF-α) after CPB were significantly decreased as compared with modified ultrafiltration group(292.84±58.23 μg/L vs. 383.79±66.24 μg/L,P=0.000; 13.32±2.31 μg/L vs. 16.41±2.65 μg/L,P=0.000); the hematocrit and serum albumin concentrations at the ten minutes after CPB were increased as compared with modified ultrafiltration group (0.39±0.04 vs. 0.35±0.03,P=0.003; 38.32±4.26 g/L vs. 34.04±2.83 g/L, P=0.003); the mechanical ventilation support time and ICU time after operation was shorted as compared with modified ultrafiltration group (Plt;0.05); main organ function was improved as compared with the modified ultrafiltration group. Conclusion The clinical application of new type ultrafiltration throughout CPB can effectively exclude some harmful inflammatory mediators, concentrate blood,short operation time,attenuate the main organ edema and injury.