The apical displacement of tricuspid valve lea?ets 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.
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.
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.
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.
The increased morbidity and mortality following cardiopulmonary bypass （CPB） may be due to the development of systemic inflammatory response syndrome （SIRS）. Leukocyte, especially neutrophil, plays a crucial role in SIRS during and after CPB, so the leukocyte removal by filtrations appears to be a logical anti-inflammatory strategy. Many articles reported that leukocyte depletion filter can decrease the potential adverse effects during CPB and reduce the morbidity and mortality following CPB. But the protective effects of the filter varied greatly from paper to paper. This may be due to the different design and biocompatibility of the filter at present, But, because the leukocyte plays a central role in SIRS, leukocyte depletion filter would be an important apparatus in therapy of noninfectious inflammation induced by CPB after it was improved.
Working Group on Extracorporeal Life Support, National Center for Cardiovascular Quality Improvement developed guidelines on patient blood management for adult cardiovascular surgery under cardiopulmonary bypass, aiming to standardize patient blood management in adult cardiovascular surgery under cardiopulmonary bypass, reduce blood resource consumption, and improve patients outcomes. Forty-eight domestic experts participated in the development of the guidelines. Based on prior investigation and the PICO (patient, intervention, control, outcome) principles, thirteen clinical questions from four aspects were selected, including priming and fluid management during cardiopulmonary bypass, anticoagulation and monitoring during cardiopulmonary bypass, peri-cardiopulmonary bypass blood product infusion, and autologous blood infusion. Systemic reviews to the thirteen questions were performed through literature search. Recommendations were drafted using the GRADE (Grading of Recommendations Assessment, Development and Evaluation) system. After five rounds of experts discussions between 2023 and 2024, 19 recommendations were finally formed.
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.