Abstract： Arginine vasopressin （AVP） is closely related to the pathogenesis of a variety of cardiovascular diseases and kidney diseases. Currently it is often used for the treatment of severe peripheral vasodilatory shock， and particularly beneficial for patients with refractory catecholamine-resistant vasodilatory shock. For some patients who do not have adequate AVP level in plasma after cardiovascular surgery， external low-dose AVP infusion is helpful to decrease the heart rate, and the dosage and duration of catecholamine use. Early initiation of low-dose AVP infusion may be beneficial for postoperative patients’ hemodynamic recovery without adverse complications. More randomized control trials are needed to provide evidence for rational usage， dosage and duration of AVP administration.
In recent years，West China Hospital of Sichuan University actively participated in medical assistance and rescue in Wenchuan，Yushu and Lushan earthquakes. However，professional roles of cardiovascular surgeons in medical assistance and rescue in earthquakes remain unclear because of the particularity of cardiovascular surgery, which often affects the assembly of medical assistance and rescue teams. Thus，we need to explore the necessity for cardiovascular surgeons to join medical rescue teams within 72 hours after earthquake. In this article，medical rescue work of cardiovascular surgeons within 72 hours after 2008 “5•12” Wenchuan earthquake and 2013 “4•20” Lushan earthquake is analyzed and compared to identify professional roles of cardiovascular surgeons in medical rescue within 72 hours after earthquake. It is necessary for cardiovascular surgeons to join medical rescue teams within 72 hours after earthquake.
Objective To introduce a novel approach using parallel placement of another oxygenator in the recirculation line as oxygen supply for oxygenator failure without circulatory arrest in cardiopulmonary bypass （CPB），and confirm its outcomes in an animal experiment. Methods A traditional piglet CPB model was established. Oxygenator failure model was established by reducing fraction of inspired oxygen （FiO2） from 80% to 21% after aortic cross-clamp and cardiac arrest in CPB. Another oxygenator was then parallel placed in the recirculation line to supply 100% oxygen.Dynamic changes in partial pressure of oxygen （PaO2），mixed venous oxygen saturation （SvO2），arterial oxygen saturation（SaO2） and blood pH of blood samples from the arterial perfusion duct were monitored with different blood flow of400 ml/min，800 ml/min and 1 100 ml/min. Results When FiO2 was reduced to 21%，PaO2 decreased to 64-67 mm Hg（P＜0.001），SaO2 decreased significantly to 88%-90% （P＜0.001），SvO2 decreased to 69%-72% （P＜0.001），and blood pH decreased too，all indicating oxygenator failure. After parallel placement of another oxygenator in the recirculation line was performed，PaO2，SaO2 and SvO2 all significantly increased，as well as blood pH. When the blood flow in the recirculation line achieved 33% or above of overall arterial perfusion flow，clinical oxygen demand was generally satisfied. Conclusion Parallel placement of another oxygenator in the recirculation line may be utilized as a treatment strategy for oxygenator failure without circulatory arrest and changeover of failed oxygenator.
Objective To summarize treatment experience and evaluate clinical outcomes of surgical therapy for Stanford type A aortic dissection （AD）. Methods Clinical data of 48 patients with Stanford type A AD who underwent surgical treatment in General Hospital of Lanzhou Military Region from October 2006 to March 2013 were retrospectively analyzed. There were 41 males and 7 females with their age of 26-72 （47.6±9.2） years. There were 43 patients with acute Stanford type A AD （interval between symptom onset and diagnosis＜14 days） and 5 patients with chronic AD. There were 19 patients with moderate to severe aortic insufficiency and 6 patients with Marfan symdrome but good aortic valve function，who all received Bentall procedure，total arch replacement and stented elephant trunk implantation. There were 8 patients with AD involving the aortic root but good aortic valve function who underwent modified David procedure，total arch replacement and stented elephant trunk implantation. There were 10 patients with AD involving the ascending aorta who received ascending aorta replacement，total arch replacement and stented elephant trunk implantation. There were 5 patients with AD involving partial aortic arch who underwent ascending aorta and hemiarch replacement. Patients were followed up in the 3rd，6th and 12th month after discharge then once every year. Follow-up evaluation included general patient conditions，blood pressure control，chest pain recurrence，mobility and computerized tomography arteriography （CTA）. ResultsCardiopulmonary bypass time was 121-500 （191.4±50.6） minutes，aortic cross-clamp time was 58-212 （112.3±31.7） minutes，and circulatory arrest and selective cerebral perfusion time was 26-56 （34.8±8.7） minutes. Postoperative mechanicalventilation time was 32-250 （76.2±35.6） hours，and ICU stay was 3-20 （7.1±3.4） days. Thoracic drainage within 24 hours postoperatively was 680-1 600 （1 092.5±236.3） ml. Seven patients （14.5%） died perioperatively including 2 patients with multiple organ dysfunction syndrome，2 patients with low cardiac output syndrome，1 patient with renal failure，1patient with delayed refractory hemorrhage，and 1 patient with coma. Twenty patients had other postoperative complicationsand were cured or improved after treatment. A total of 38 patients ［92.7% （38/41）］ were followed up for 3-48 （13.0±8.9） months，and 3 patients were lost during follow-up. During follow-up，there were 36 patients alive and 2 patients who died of other chronic diseases. There was no AD-related death during follow-up. None of the patients required reoperation for AD or false-lumen expansion. CTA at 6th month after discharge showed no anastomotic leakage，graft distortion or obstruction.Conclusion According to aortic intimal tear locations，ascending aorta diameter and AD involving scopes，appropriate surgical strategies，timing and organ protection are the key strategies to achieve optimal surgical results for Stanford type A AD. Combined axillary and femoral artery perfusion and increased lowest intraoperative temperature are good methods for satisfactory surgical outcomes of Stanford type A AD.