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.
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.
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.
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.
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.
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.
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.
ObjectiveTo observe the efficacy of platelet-rich fibrin (PRF) membrane tamponade combined with air filling for giant macular hole (MH). MethodsA prospective case-control study. From January 2019 to February 2021, 56 patients (56 eyes) diagnosed with giant MH from Eye Center of Renmin Hospital of Wuhan University were enrolled. Among them, there were 17 males with 17 eyes and 39 females with 39 eyes. The average age of the patients was 64.23±9.30 years old. The average MH minimum diameter was 827.36±83.16 μm. The best corrected visual acuity (BCVA) and optical coherence tomography angiography (OCTA) examination were performed before surgery. The Chinese version of 25-item National Eye Institute visual functioning questionnaire (NEI VFQ-25) was used to investigate patient's visual-related quality of life. There were 28 eyes of 28 cases receiving PRF membrane covering, as PRF group, another 28 eyes of 28 cases receiving inverted internal limiting membrane (ILM) insertion into giant MH, as ILM group. The differences of the age (t=－1.588), sex ratio (χ2=0.760), BCVA (Z=－0.400), macular hole minimum diameter (t=－0.604), choriocapillary blood flow area (CBFA) (t=1.331) and NEI VFQ-25 score (t=0.921) were not statistically significant (P＞0.05). All eyes underwent 23G minimally invasive vitrectomy. In the PRF group, PRF membrane was used to fill the hole, and in the ILM group, the hole was filled with ILM inversion, and filled with sterile air after full gas-liquid exchange. The follow-up time after surgery was ≥6 months. The same equipment and methods as before surgery were used to conduct related examinations, and the changes of BCVA, the shape of hole closure, CBFA and the improvement of vision-related quality of life were compared between the two groups. For comparison between groups, independent samples t-test was used for data with normal distribution, and Mann-Whitney U test was used for data with non-normal distribution. For intra-group comparisons, paired-samples t-test was used for data with normal distribution, and Wilcoxon rank-sum test was used for non-normally distributed data. ResultsSix months after surgery, in the eyes of PRF group and ILM group, the hole of 27 (96.4%, 27/28) and 26 (92.6%, 26/28) eyes were closed; the median BCVA was 0.70 and 0.70, respectively; CBFA were 1.99±0.20 and 1.91±0.18 mm2; NEI VFQ-25 scores were 81.36±12.39 and 78.39±10.12, respectively. Compared with before surgery, the BCVA (Z=－4.636,－4.550) and CBFA (t=－27.115,－31.135) of the affected eyes in the PRF group and ILM group were significantly improved after surgery, and the NEI VFQ-25 scores (t=－15.557, －10.675) was significantly increased, and the difference was statistically significant (P＜0.05). There was no significant difference in BCVA (Z=－0.167), CBFA (t=1.554), and NEI VFQ-25 scores (t=0.980) between the two groups after interocular surgery (P=0.726, 0.126, 0.331). ConclusionPRF membrane insertion with air filling has the same efficacy as ILM insertion in the treatment of giant MH, which can improve the closure rate of MH, patients' vision and vision-related quality of life, and increase choroidal blood perfusion.