Objective To investigate the methods and effectiveness of multi ple surgical treatment for complex aortic arch and descending aorta disease, including cardiopulmonary bypass operation, hybrid operation, and total endovascular aneurysm repair (EVAR). Methods Between October 2006 and September 2011, 48 patients with complex aortic arch anddescending aorta disease were treated. There were 31 males and 17 females, aged from 28 to 81 years (mean, 52.4 years). The disease duration ranged from 1 to 90 days (mean, 10.2 days). There were 30 cases of type B aortic dissection involving the aortic arch, 11 cases of thoracic aortic aneurysm, 3 cases of thoracic pseudoaneurysme, 3 cases of penetrating aortic ulcer, and 1 case of aortoesophageal fistula. Cardiopulmonary bypass operation, hybrid operation, and total EVAR were performed in 15, 12, and 21 cases, respectively. Results In the patients undergoing cardiopulmonary bypass operation, the following complications occurred: 1 case of bleeding, 1 case of coma, 3 cases of psychiatric disorders, 4 cases of pneumonia, 2 cases of acute renal insufficiency, and 2 cases of multi-organ dysfunction; finally 3 patients died. In the patients undergoing hybrid operation, cerebral infarction and renal function failure occurred in 1 case. In the patients undergoing total EVAR, no complication occurred. A total of 41 patients were followed up 2 to 60 months (mean, 28.6 months). Sl ight left subclavian steal syndrome occurred in 3 cases, but self rel ieved. Other patients recovered to normal l ife. Conclusion In the surgical treatments of complex aortic arch and descending aorta disease, cardiopulmonary bypass operation will be gradually replaced by EVAR because of the surgical trauma and risk, hybrid operation is an important technique, and total EVAR will be the future progress.
摘要:目的: 評價機械通氣對胸腔內脈搏氧飽和度的影響。 方法 :以食道、氣管和降主動脈作為胸腔內脈搏氧飽和度的監測位點,將改制后的氧飽和度探頭分別固定于上述部位,并連接于同一監護儀上。純氧通氣,待上述氧飽和度容積波波形和讀數穩定,停止機械通氣30s。以錄像的方式記錄機械通氣停止前后30 s內食道、氣管和降主動脈SpO2容積波和讀數的變化。同時記錄舌SpO2。 結果 :機械通氣時,食道、氣管和降主動脈三個監測位點均可獲得異常高大的SpO2容積波;停止通氣時,異常高大的氧飽和度波形消失。食道、氣管和降主動脈脈搏容積波變異率分別為112%,74%,302%。降主動脈脈搏容積波的變異率明顯高于食道和氣管( 〖WTBX〗P ＜005)。機械通氣停止前后30s內食道、氣管和降主動脈的SpO2讀數變化無顯著差異(〖WTBX〗P ＞005)。 結論 :機械通氣對胸腔內食道、氣管和降主動脈氧飽和度讀數無影響,主要影響是脈搏容積波。且各位點間脈搏氧容積波受呼吸的影響不同。Abstract: Objective: To investigate the impact of mechanical ventilation on pulse oximetry in thoracic cavity. Methods : After dogs anesthesia induction and thoracotomy, pulse oximeters were simultaneously placed at esophagus, trachea, and descending aorta, and connected with the same monitor for SpO2 monitoring. During ventilation with 100% oxygen, the mechanical ventilator was temporarily switched off for 30 seconds after high quality PPG waveforms and SpO2 readings were obtained. SpO2 signals and readings from esophagus (SeO2), trachea (StraO2), descending aorta (SDAO2) shown on the monitoring screen were recorded by the SONY video before and after stopventilation. And StonO2 were also recorded. Results : Abnormally largeamplitude PPG waves were found in normal waves at monitoring sites of esophagus, trachea, and descending aorta in all animals during ventilation; however, they disappeared without ventilator. The variation rate in ventilationinduced PPG amplitude were 112%, 74%, 302% at esophagus, trachea and descending aorta respectively. The PPG amplitude variation rate from SDAO2 was higher than that from SeO2 and StraO2 (〖WTBX〗P ＜005). However, the SpO2 readings obtained from pulse oximetries in all sites were no significantly statistical difference within 30s before and after temporarily stopventilation (〖WTBX〗P ＞005). Conclusion : Abnormally amplitude PPG waveforms from oximetry probe placed at esophagus, trachea, and descending aorta were induced by ventilation. The Variation rate in ventilationinduced PPG amplitude was various at different monitoring sites. The SpO2 readings from esophagus, trachea, and descending aorta were not significantly contaminated by ventilation.
The mechanical properties of the aorta tissue is not only important for maintaining the cardiovascular health, but also is closely related to the development of cardiovascular diseases. There are obvious differences between the ventral and dorsal tissues of the descending aorta. However, the cause of the difference is still unclear. In this study, a biaxial tensile approach was used to determine the parameters of porcine descending aorta by analyzing the stress-strain curves. The strain energy functions Gasser-Ogden-Holzapfel was adopted to characterize the orthotropic parameters of mechanical properties. Elastic Van Gieson (EVG) and Sirius red stain were used to observe the microarchitecture of elastic and collagen fibers, respectively. Our results showed that the tissue of descending aorta had more orthotropic and higher elastic modulus in the dorsal region compared to the ventral region in the circumferential direction. No significant difference was found in hyperelastic constitutive parameters between the dorsal and ventral regions, but the angle of collagen fiber was smaller than 0.785 rad (45°) in both dorsal and ventral regions. The arrangement of fiber was inclined to be circumferential. EVG and Sirius red stain showed that in outer-middle membrane of the descending aorta, the density of elastic fibrous layer of the ventral region was higher than that of the dorsal region; the amount of collagen fibers in dorsal region was more than that of the ventral region. The results suggested that the difference of mechanical properties between the dorsal and ventral tissues in the descending aorta was related to the microstructure of the outer membrane of the aorta. In the relatively small strain range, the difference in mechanical properties between the ventral and dorsal tissues of the descending aorta can be ignored; when the strain is higher, it needs to be treated differently. The results of this study provide data for the etiology of arterial disease (such as arterial dissection) and the design of artificial blood vessel.