RESUMO
Objective To modify the existing preparation instrument for medical patch material to realize its scale and automatic production.Methods The instrument had its shaking table improved and a cylindrical processing system added with comprehensive analysis on raw materials and kinds of process flows.A spreading and fixation mechanism for animal materials was placed in the cylindrical processing system,which had the holes for liquid inlet and outlet respectively on its top and bottom.The cylindrical processing system was fixed to the base of the shaking table.Results The instrument enhanced preparation efficiency significantly,and had the raw material utilization rate increased by 20％,product qualification rate raised by 35％,preparation cycle reduced by 33％ and total cost saved by 40％.Conclusion The instrument behaves well in adaptability to multi animals,preparation process,inter-assay difference,raw material utilization rate,product qualification rate and cost reduction,which is of great significance to promote the clinical application of medical biological patch.
RESUMO
Objective To report the primary experience of open placement of triple-branched stent graft for acute Stanford type A aortic dissection. Methods Between June 2008 and September 2009, 20 well-selected patients with acute Stanford type A aortic dissection underwent open placement of triple-branched stent graft for total arch reconstruction. When core cooling to a 20℃ nasophageal temperature, perfusion to the lower body was discontinued and the ascending aorta was transected at the base of the innominate artery. Through a transverse incision, the triple-branched stent graft was inserted into the true lumen of the arch and descending aorta, and each side arm of the stent graft was positioned one by one into the arch branches.The transected stump of the ascending aorta was reconstructed by inner proximal stent-free dacron tube of the main graft and outer teflon felt, and subsequently continuous anastomosis to the 1-branched dacron tube graft was made. Results Open placement of triple-branched stent graft was technically successful in all patients. The mean cardiopulmonary bypass time, aortic cross-clamp time and lower body arrest time were (163.2 ±19.2) min, (89.4 ±10.0) min and (32. 7 ±6. 6)min, respectively. Transient postoperative neurological dysfunction was observed in 1 patient and acute renal failure in 1 patient. All patients were discharged from the hospital. Their computed tomographic scans at 3 months postoperatively showed that all stent grafts were fully opened without distortion. In the vascular stent implantation site the dissected false lumen was eliminated. The false lumen of the descending aorta distal to the stent graft was closed with thrombus in 16 cases. Conclusion Open placement of triple-branched stent graft is a new effective technique for total arch reconstruction in acute type A aortic dissection. Patients have the indications of the extensive primary repair of the thoracic aorta without primary intimal tears in the arch may be the best candidates for this new technique. The size of the stent graft, the distances between two neighboring side arm grafts and the prevention of the intimal trauma during the placement are crucial for successful open placement of triple-branched stent graft.