ObjectiveTo observe the changes in physical properties of silicone oil after intraocular tamponade. MethodsThe silicone oil was removed from 99 patients (99 eyes) of primary retinal detachment with 23G vitreous cutter system. The upper silicone oil was collected after put the vitrectomy samples at room temperature for 3 days. According to the time of intraocular tamponade, the silicone oil samples were divide into six groups including group A (1 month, 12 samples), group B (2 months, 15 samples), group C (3 months, 25 samples), group D (6 months, 22 samples), group E (1-2 years, 13 samples) and group F (above 2 years, 12 sample). Fresh unused silicone oil was set as blank control group. Then the emulsion particles, kinematic viscosity, surface tension, density, transmittance and refractive index were measured. ResultsThe difference between group A-F and the control was statistical significant (P<0.05) in emulsion particles (F=89.337), kinematic viscosity (F=10.660), surface tension (F=11.810), density (F=13.497), transmittance of wavelengths (F=455.496, 566.105, 525.102, 767.573, 622.961, 601.539), but not statistical significant at refractive index (F=2.936, P>0.05). The number of silicone oil emulsion particles has no statistical difference between group A and the control (P>0.05), but was significantly different between group B-F (P<0.05). The kinematic viscosity of silicone oil has no statistical difference between group A, B and the control (P>0.05), but was significantly different between group C-F (P<0.05). The surface tension of silicone oil has no statistical difference between group A-D and the control (P>0.05), but is significantly different between group E and F (P<0.05). The density of silicone oil has no statistical difference between group A-D and the control (P>0.05), but was significantly different between group E and F (P<0.05). The transmittance of silicone oil has statistical difference between group A-F and the control(P<0.05). The refractive index of silicone oil has no statistical difference between all the groups and the controls significantly (P>0.05). ConclusionsThe physical properties of silicone oil will change during the intraocular tamponade. The emulsion particles number will increase and the transmittance will decrease after 2 months, the kinematic viscosity of silicone oil will decrease significantly after 3 months, and the density and surface tension will change significantly after 1 year of tamponade.
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.
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.
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.
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.
From aortic declamping to weaning from cardiopulmonary bypass (CPB), myocardium needs recovery not only from surgical and ischemia/reperfusion injury, but also of its full performance of pumping function as quickly as possible. In the early period of resuming myocardial perfusion, coronary blood flow should be increased, but ventricular volume overload, large dosage of adrenaline and isoprenaline, and high-energy defibrillation should be avoided. Thenappropriate management according to cardiac function and ECG changes is needed for successful weaning from CPB.
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.