Abstract： Objective To evaluate the clinical safety and neurological outcomes of right axillary artery cannulation with a side graft compared with a direct approachin aortic arch replacement for patients with acute Stanford type A aortic dissection. Methods Between July 2008 and July 2010， 280 consecutive patients with acute Stanford type A aortic dissection underwent right axillary artery cannulation for cardiopulmonary bypass （CPB） in total arch replacement and stented “elephant trunk” implantation in our hospital.These 280 patients were divided into two groups according to the method of axillary artery cannulation in operation:direct arterial cannulation was used in 215 patients（direct arterial cannulationgroup， DG group， mean age of 43.1±9.5 years）， while cannulation with a side graft was used in 65 patients（ indirect cannulation group， IG group， mean age of 44.7±8.3 years）. Clinical characteristics of both groups were similar except their axillary artery cannulation method. Patient outcomes were compared as to the prevalence of clinical complications， especially neurological deficits and postoperative morbidity. Results The overall hospital mortality was 3.6% （10/280）， 3.3% （7/215） in DG group and 4.6% （3/65） in IG group respectively.Right axillary artery cannulation was successfully performed in all cases without any occurrence of malperfusion. Postoperatively， 25 patients（8.9%）developed temporaryneurological deficits， 19 cases in DG group（8.8%）， and 6 cases in IG group （9.2%）， and all these patients were cured after treatment. The incidence of postoperative complications directly related to axillary artery cannulation was significantly lower in IG group than that in DG group（1 case vs. 19 cases， P=0.045）. There were no statistical differences in arterial perfusion peak flow， peak pressure，antegrade cerebral perfusion time， deep hypothermic circulatory arrest time， and CPB time between the two groups（P ＞ 0.05）. Conclusion Right axillary artery cannulation with a side graftcan significantly reduce the postoperative complications of axillary artery cannulation. It is a safe and effective method for patients undergoing surgery for acute Stanford type A aortic dissection.
Deep hypothermic circulatory arrest (DHCA) technology is the basic means of organ protection in complex aortic arch surgeries, congenital heart disease surgeries, pulmonary endarterectomy and other operations. The establishment of DHCA in rat model is helpful to explore the influence of DHCA and its pathophysiological pathways. However, there are some problems in this process, such as imperfect monitoring, inaccurate management and non-standard heparinization during the experimental period. It is necessary to review relevant literatures on DHCA rat model, in order to establish a DHCA rat model with standardized operation, clear standards and mature technology.
Objective To observe the influence of edaravone perfusion via the pulmonary artery on postoperative lung tissue and lung function during pulmonary ischemia in deep hypothermic circulatory arrest （DHCA）， and explore its possible mechanism. Methods A total of 24 healthy New Zealand white big-ear rabbits were randomly divided into three groups： （1） control group： DHCA model under cardiopulmonary bypass （CPB） was established； （2）low potassium dextran （LPD）group： LPD solution perfusion via the pulmonary artery after the establishment of DHCA； （3）edaravone group：LPD solution containing edaravone （5 mg/kg） perfusion via the pulmonary artery after the establishment of DHCA. Oxygenation index and lung compliance were observed at the time of baseline condition， recovery of ventilation， 1 hour and 2 hours after recovery of ventilation， and postoperative lung function of the three groups were compared. Malondialdehyde （MDA） and superoxide dismutase （SOD） in pulmonary venous blood were measured. All the rabbits were sacrificed after the operation. HE staining and immunohistochemistry were performed on the lung tissues to investigate lung structure changes and inflammatory reaction. Transmission electron microscopy was used to compare ultrastructural changes of lung.Results There were no statistical difference in oxygenation index， lung compliance， MDA and SOD among the 3 groups under the baseline condition （P＞0.05）. After recovery of ventilation， oxygenation index and lung compliance deteriorated to varying degrees in all 3 groups. Oxygenation index and lung compliance of the control group and LPD group at the time of recovery of ventilation， 1 hour and 2 hours after recovery of ventilation were significantly lower than those of edaravone group （oxygenation index：recovery of ventilation and in control group and edaravone group: 198.25±11.02 mm Hg vs. 244.87±13.05 mm Hg；lung compliance：one hour after recovery ventilation in control group and edaravone group：45.88±1.64 ml/cm H2O vs. 59.75±2.38 ml/cm H2O；P＜0.05）. After CPB removal， MDA levels were increased to varying degrees in all 3 groups. MDA levels of the control group and LPD group at the time of CPB removal， 1 hour and 2 hours after CPB removal were significantly higher than those of edaravone group （P＜0.05）. After CPB removal， SOD levels were decreased to varying degrees in all 3 groups. SOD levels of the control group and LPD group at the time of CPB removal， 1 hour and 2 hours after CPB removal were significantly lower than those of edaravone group （P＜0.05）. HE staining showed clear lung structure， less red blood cell leakage， less inflammatory cell infiltration， and less alveolar fluid accumulation in the edaravone group. Immunohistochemistry showed that integral light density of interleukin 6 （IL-6）in edaravone group was significantly lower than those of the LPD group and control group （14.44±1.75 vs. 20.18±2.22， P＜0.05）. Transmission electron microscopy showed integral basement membrane structure， clear blood gas barrier structure， significantly larger number of type II epithelial cells， abundant but not swollen mitochondria and lamellar bodies in the cytoplasm in the edaravone group， which were destroyed in varying degrees in the LPD group and control group. Conclusion Pulmonary artery perfusion of protective solution in low temperature can significantly reduce lung injury induced by DHCA and CPB. Protective solution containing edaravone in low temperature can better decrease lung injury and protect oxygenation.
ObjectiveTo investigate the impact of deep hypothermic circulatory arrest (DHCA) with antegrade cerebral perfusion (ACP) on cognitive function of patients undergoing surgical therapy for acute Stanford type A aortic dissection (AD). MethodsBetween January 2009 and March 2012, 48 patients with acute Stanford type A AD underwent Sun's procedure (aortic arch replacement combined with stented elephant trunk implantation) under DHCA with ACP in Nanjing Hospital affiliated to Nanjing Medical University. There were 40 males and 8 females with their age of 51.3±13.6 years. Circulatory arrest time and time for postoperative consciousness recovery were recorded. Preoperative and postoperative cognitive functions of each patient were evaluated by mini-mental status examination (MMSE). ResultsMean cardiopulmonary bypass time of the 48 patients was 237.3±58.5 minutes, and mean circulatory arrest time was 37.3 ±6.9 minutes. Four patients died postoperatively with the causes of death including lung infection, multiple organ dysfunction syndrome, myocardial infarction and acute respiratory distress syndrome. Forty-one patients recovered their consciousness within 24 hours postoperatively, and the mean time for postoperative consciousness recovery was 15.3±6.5 hours. Preoperative MMSE score was 28.6±1.1 points, and MMSE score at 1 week postoperatively was 23.6±4.5 points. Thirty-one patients were followed up for 6 months with the follow-up rate of 70.45%. The average MMSE score of the 31 patients at 6 months after surgery was 27.6±2.1 points which was significantly higher than postoperative average MMSE score (P < 0.05), but not statistically different from preoperative average MMSE score (P > 0.05). ConclusionsDHCA with ACP can provide satisfactory cerebral protection for patients undergoing surgical therapy for acute Stanford type A AD, but patients' cognitive function may be adversely affected in the short term. As long as cerebral infarction or hemorrhage is excluded in CT scan of the brain, such adverse impact may generally disappear automatically within 6 months after surgery.
To valuate cerebral protection by retrograde cerebral perfusion (RCP) via superior vena cava,the study results for the last ten years have been reviewed.RCP is regarded as an assistant method in deep hypothermic circulatory arrest(DHCA) in that it provides partial brain blood flow,maintains a low brain temperature,optimizes cerebral metabolic function during DHCA by supplying oxygen and some nutrient and removal of catabolic products;it also reduces the incidence of cerebral embolization by flushing out air...
Objective To summarize the efficacy of aortic arch 1 zone clamping technique in the procedure of ascending aortic aneurysm involving the proximal aortic arch. Methods The clinical data of patients with ascending aortic aneurysm involving the proximal aortic arch who underwent surgical treatment with aortic arch 1 zone clamping technique in our hospital from 2017 to 2019 were retrospectively analyzed. ResultsA total of 35 patients were enrolled, including 21 males and 14 females, with an average age of 63.9±10.8 years. According to different lesions, the proximal aorta underwent Bentall/Carbrol procedure in 8 patients, Wheat in 4 patients, David in 3 patients, and ascending aorta replacement in 20 patients. Distal lesions were completely resected under aortic arch 1 zone clamping technique, and anastomotic reconstruction was performed under hypothermic cardiopulmonary bypass. Distal anastomosis was performed with interrupted suture in 7 patients, and continuous suture with intermittent reinforcement of the posterior wall in 28 patients. All patients successfully completed the procedure. The average cardiopulmonary bypass time was 121.5±28.2 min, the aortic clamping time was 78.1±21.3 min, and the distal anastomosis time was 15.2±3.6 min. One patient underwent a second thoracotomy for hemostasis, and the remaining patients were drained 330.6±108.1 mL on the first day following the procedure. The postoperative mechanical ventilation time of 2 patients exceeded 24 hours, and the main complications were pulmonary infection in 1 patient and acute renal injury in 2 patients. Transient delirium occurred in 2 patients and no transient or permanent neurological dysfunction occurred. The average follow-up time was 2.6±1.1 years. The maximum diameter of the ascending aorta after operation was 30.4±0.9 mm, the diameter of zone 1 aortic arch was 39.8±3.1 mm, and the diameter of the distal aortic arch was 32.3±4.3 mm. There was no lesion in the artificial blood vessels of all patients, and no aneurysms occurred at the proximal or distal anastomosis. No reoperation or intervention was needed for the aorta. ConclusionThe aortic arch 1 zone clamping technique can simplify the procedure of ascending aortic aneurysm involving the proximal aortic arch, reduce or avoid the use of deep hypothermic circulatory arrest, reduce the surgical trauma, and has good short-term and medium-term efficacy.
Deep hypothermic circulatory arrest (DHCA) is an important assistant technique for complex cardiac surgery, which creates convenient operating conditions for surgery, and is also one of the measures to protect the brain during operation. However, the complications caused by this technique cannot be ignored, and it should be noticed that the occurrence of intestinal injury is relatively insidious, but brings great pain to patients and significantly reduces the quality of life after operation. Studies have shown that intestinal ischemia-reperfusion injury is induced by DHCA. It causes mast cells to activate and release many inflammatory mediators that destroy the intestinal mucosal epithelium barrier, and eventually lead to intestinal injury. This article reviewed the research progress of mast cells in the mechanism of DHCA-induced intestinal injury.
Abstract： Objective To investigate the cerebral protective effects of hyperoxia management during deep hypothermia circulatory arrest（DHCA） rabbit by the blood gas indexes, superoxide dismutase（ SOD） activity and malondialdehyde （MDA） levels of brain, and ratio of water to brain. Methods A DHCA and antegrade selective cerebral perfusion （ASCP） rabbit model was established. Twenty-four 11-13 week-old male New Zealand rabbits（ weighing 2.7 to 3.4 kg） were assigned to three groups with a random number table: a sham operation group （Sham group）, an ASCP group （S group）, and an ASCP ＋ hyperoxia management group （SH group）. There were eight rabbits in each group. We recorded the intraoperative values for arterial oxygen pressure （PaO2）, arterial oxygen saturation （SaO2）, jugular venous oxygen pressure（PjvO2）, jugular venous oxygen saturation（ SjvO2） and blood lactate level. The brain SOD activity, MDA levels, and ratio of water to brain were measured after the operation. Results Before initiating circulatory arrest, before initiating reperfusion and five minutes of reperfusion, levels of PaO2 , PjvO2 , and SjvO2 in the SH group were significantly higher than those of the S group and Sham group. SOD activity in the SH group was not significantly different from that of the S group[（213.53±33.52） U/mg. prot vs. （193.02±27.67） U/mg. prot] and Sham group[（213.53±33.52） U/mg. prot vs.（244.38±35.02）U/mg. prot], but the SOD activity in the S group was lower than that in the Sham group（ P ＜ 0.05）. MDA levels in the SH group were lower than that in the S group[（1.42±0.30） nmol/mg. prot vs. （2.37±0.55） nmol/mg. prot, P ＜ 0.05]. Conclusion Our data show that hyperoxia management during DHCA＋ASCP improves rabbits’PjvO2 and SjvO2, maintains brain SOD activity, and decreases brain MDA levels, demonstrating the neuroprotective effects of hyperoxia mangagement.
Objective To investigate different gases and hematocrits on cerebral injury during deep hypothermic circulatory arrest (DHCA) in a piglet model including monitoring by near-infrared spectroscopy (NIRS). Methods Twenty-four piglets were assigned to 4 groups with respect to different blood gas and hematocrit during DHCA. Group A: hematocrit was maintained between 0.25 to 0.30, pH-stat strategy during cooling phases and alpha stat strategy in other phases; group B: hematocrit was maintained between 0.25 to 0.30 and alpha stat strategy; group C: hematocrit was maintained between 0.20 to 0.25, pH-stat strategy during cooling phases and alpha stat strategy in other phases; group D: hematocrit was maintained between 0.20 to 0.25 and alpha stat strategy. Cerebral oxygenations of piglets were monitored continuously by NIRS. The brain was fixed in situ at 6 hours after operation and a histological score for neurological injury was assessed. Results Oxygenated hemoglobin (HbO2) and total hemoglobin (HbT) signals detected by NIRS were significantly lower in group D than those in group A and group B during cooling (Plt;0.05). Oxygenated hemoglobin nadir time was significantly shorter in group A(Plt;0.05). All piglets with oxygenated hemoglobin signal nadir time less than 25 minutes were free from histological evidence of brain injury. Conclusion Combination of pH-stat strategy and higher hematocrit reduces neurological injury after DHCA.
Abstract: Objective To observe the influence of various methods of cerebral protection during deep hypothermic circulatory arrest (DHCA ) on S-100 protein. Methods Eighteen dogs were randomly and equally divided into three groups: the deep hypothermic circulatory arrest (DHCA group ) , the DHCA with retrograde cerebral perfusion (DHCA + RCP group ) , and the DHCA with intermittent antegrade cerebral perfusion (DHCA + IACP group ). Upon interruption of cardiopulmonary bypass (CPB) , the nasopharyngeal temperature was slowly lowered to 18℃, before CPB was discontinued for 90 minutes, after 90 minutes, CPB was re-established and the body temperature was gradually restored to 36℃, then CPB was terminated. Before the circulatory arrest, 45min, 90min after the circulatory arrest and 15min, 30min after re-established of CPB, blood samples were drawn from the jugular veins fo r assay of S-100 protein. Upon completion of surgery, the dogs was sacrificed and the hippocampus was removed from the brain, properly processed for examination by transmission electron microscope for changes in the ultrastructure of the brain and nerve cells. Results There was no significant difference in the content of S-100 protein before circulatory arrest among all three groups (P gt; 0.05). After circulatory arrest, DHCA and DHCA +RCP group showed an significant increase in the content of S-100 protein (P lt; 0.01). There was no significant difference in the content of S-100 protein after circulatory arrest in DHCA + IACP group. Conclusion Cerebral ischemic injuries would occur if the period of DHCA is prolonged. RCP during DHCA would provide protection for the brain to some extent, but it is more likely to cause dropsy in the brain and nerve cells. On the other hand IACP during DHCA appears to provide better brain protection.