The apical displacement of tricuspid valve leaflets complicated with significantly enlarged, thin and fibrotic wall of the right ventricle is prone to dysfunction of right heart. Therefore, the myocardial protection for the right ventricle is important. Based on the pathological changes, an algorithm of perioperative myocardial protection strategy is summarized. Firstly, we should clearly know that the right ventricular myocardium with severe lesions is much different from the unimpaired myocardium, because it is now on the margin of failure; secondly, right heart protection should be regarded as a systematic project, which runs through preoperative, intraoperative and postoperative periods, and requires close collaboration among surgeons, perfusionists, anesthesiologists and ICU physicians. In this article, we try to introduce the systematic project of the right heart protection, in order to improve the outcome of this population.
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.
Abstract： Objective To compare individualized protamine with protamine based on weight in terms of postoperative bleeding and blood transfusion dose, in order to reduce postoperative bleeding complications. Methods Forty adult patients scheduled to elective open heart surgery under cardiopulmonary bypass （CPB） were randomly divided into two groups. For patients in the experimental group, we gave them protamine based on heparinprotamine titration result, while patients in the control group received the same amount of protamine as the heparin administered before operation. Pleural drainage and required transfusion were recorded at 1, 2 and 24 hours after surgery. Results Protamine dose given to the experimental group was significantly higher than the control group (Plt;0.05), while pleural drainage was significantly lower at 1 h(180±83 ml vs. 285±156 ml,P=0.012), 2 h (74±31 ml vs. 114±44 ml，P=0.002), and 24 h (465±167 ml vs. 645±207 ml，P=0.004) than that in the control group after surgery, and the required red blood cell suspension was also significantly lower than the control group (0.15±0.27 U vs.0.80±0.96 U,P=0.018). Conclusion Compared with protamine dose based on heparin administered before CPB, individualized protamine based on titration can reduce postoperative pleural drainage (blood loss) and red blood cell suspension requirement.
Cardiac injury is a major complication of cardiac surgery. Surgical manipulation, systemic inflammatory response and cardiac ischemia/reperfusion injury (IRI)are main reasons of cardiac injury. Gentle and swift surgical manipulation can reduce mechanical myocardial injury, shorten myocardial ischemic time, and reduce myocardial IRI. Satisfactory myocardial protection plays a key role to improve postoperative recovery. In recent years, more and more myocardial protection strategies are employed to reduce myocardial IRI and improve myocardial protection, including modifications of temperature, composition and instillation approach of cardioplegia in order to increase myocardial oxygen supply, decrease myocardial oxygen consumption, inhibit inflammatory response and eliminate oxygen free radicals. Endogenous myocardial protection is also achieved by supplement of certain medications in cardioplegia.
There is a close relationship between inflammation and coagulation response. Inflammation and coagulation are activated simultaneously during cardiopulmonary bypass, which induce postperfusion syndrome. Leukocyte depletion filter can inhibit inflammation by reducing neutrophils in circulation. But, its effects on blood conservation are limited. Aprotinin is a serine protease inhibitor, and can prevent postoperative bleeding by anti-fibrinolysis and protection of platelet function. But its effects on anti-inflammation and protection of organs are subjected to be doubted. The combination of leukocyte depletion filter and aprotinin can inhibit inflammation as well as regulate coagulation, and may exert a good protective action during cardiopulmonary bypass.
Objective To assess the protective effects of a new type of leukocyte-depletion filter-1 (LD-1) on red blood cells during cardiopulmonary bypass(CPB). Methods Twelve Mongolian dogs, weight range 25-30kg, were divided into control group and leukocyte depletion group (LD group) with random number table, LD group (n=6) had our new type of leukocyte depletion filter-1 placed in venous line which was used within the first 5 minutes after onset of CPB. The control group (n=6) had no leukocyte depletion filter installed in the circuit. CPB was set up by cannulated with a venous cannula through the right atrium and with an aortic cannula after median sternotomy. Aorta was clamped at 10 minutes of CPB and released at 70 minutes of CPB. Dogs were observed for 2 hours after weaning from CPB. Blood samples were collected prior to, at 10, 40, 75 minutes, end of and 2 hours after CPB to determine circulating leukocytes, erythrocyte fragility and plasma levels of malondialdehyde(MDA), superoxide dismutase(SOD) and free hemoglobin(FHB). Results Leukocyte numbers were significantly reduced in LD group during CPB(Plt;0.01), and lower than those in control group (Plt;0.05). Plasma levels of SOD dropped after 75 minutes of CPB in control group, but those kept normal in LD group, and higher than those in control group at 2 hours after CPB (Plt;0.05, 0.01). Serum MDA and FHB levels increased sharply in two groups (Plt;0.01), but were lower in LD group than those in control group. The concentrations of NaCl when starting and complete hemolysis were also lower in LD group than those in control group at end of and 2 hours after CPB. Conclusion The new type of LD-1 used in venous line only 5 minutes after onset of CPB can decrease leukocyte counts, and reduce erythrocyte injury effectively.
In left heart disease, pulmonary artery pressure would increase due to the elevated left atrial pressure. This type of pulmonary hypertension (PH) is belonged to type Ⅱ as a passive PH (pPH) in its classification. The essential cause of pPH is excessive blood volume. Recently, we have identified another type of pPH, which is induced by vasopressors. Vasopressor-induced pPH shares similar pathophysiological manifestations with left heart disease-induced pPH. pPH would, therefore, be aggressive if vasopressors were applied in patients with left heart disease, which may be common after cardiac surgery, because heart undergoing surgical trauma may require support of vasopressors. Unfortunately, pPH after cardiac surgery is often ignored because of the difficulty in diagnosis. To improve the understanding of pPH and its effect on outcomes, here we highlight the mechanisms of interaction between vasopressor-induced and left heart failure-induced pPH, and provide insights into its therapeutic options.
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.