Objective To determine risk factors associated with postoperative hypoxemia after surgery for acute aortic dissection. Methods We retrospectively analyzed clinical data of 116 patients with acute aortic dissection who underwent endovascular stent-graft exclusion or open surgery in Qingdao Municipal Hospital from February 2007 to February 2012. All the 116 patients were diagnosed as acute aortic dissection by CT angiography （CTA），including 60 patients with Stanford type A aortic dissection and 56 patients with Stanford type B aortic dissection. According to whether they had postoperative hypoxemia，all the 116 patients with acute aortic dissection were divided into hypoxemia group［arterial partial pressure of oxygen （PaO2） /fraction of inspired oxygen （FiO2） ＜200 mm Hg］：33 patients including 28 males and 5 females with their age of 52.7±11.4 years； and non-hypoxemia group（PaO2/FiO2≥200 mm Hg）：83 patients including 66 males and 17 females with their age of 55.0±13.8 years. Perioperative clinical data were analyzed and compared between the two groups. Multivariate logistic regression was performed to identify risk factors of postoperative hypoxemia after surgery for acute aortic dissection. Results The incidence of postoperative hypoxemia after surgery for acute aortic dissection was 28.4% （33/116）. Perioperative death occurred in 13 patients（11.2%，including 8 patients in the hypoxemia group and 5 patients in the non-hypoxemia group）. Univariate analysis showed that preoperatively the percentages of patients with body mass index（BMI） ＞ 25 kg/m2，smoking history，duration from onset to operation ＜24 h，preoperative PaO2/FiO2≤300 mm Hg，and patients undergoing open surgery in the hypoxemia group were significantly higher than those in the non-hypoxemia group（P＜0.05）. Deep hypothermic circulatory arrest（DHCA） ratio，blood transfusion in 24 hours postoperatively，mechanical ventilation time，length of ICU stay and hospital stay in the hypoxemia group were significantly higher or longer than those in the non-hypoxemia group（P＜0.05）. Logistic multivariate regression identified BMI＞25 kg/m2（RR=98.861，P=0.006），DHCA（RR=22.487，P=0.007），preoperative PaO2/FiO2≤300 mm Hg（RR=9.080，P=0.037） and blood transfusion＞6 U in 24 hours postoperatively（RR=32.813，P=0.003） as independent predictors of postoperative hypoxemia for open-surgery patients，while BMI＞25 kg/m2 （RR=24.984，P=0.036） and preoperative PaO2/FiO2 ratio≤300 mm Hg （RR=21.145，P=0.042） as independent predictors of hypoxemia for endovascular stent-graft exclusion patients. Conclusion Postoperative hypoxemia is a common complication after surgery for acute aortic dissection. Early interventions for obesity and preoperative hypoxemia，and reducing perioperative blood transfusion may decrease the incidence of postoperative hypoxemia after surgery for acute aortic dissection.
Abstract: Objective To evaluate surgical strategies for the treatment of acute Stanford type A aortic dissection with involvement of the aortic root. Methods From January 2005 to December 2010, 62 consecutive patients underwent emergency surgical intervention for acute Stanford type A aortic dissection with involvement of the aortic root in Renji Hospital Affiliated to Medical School of Shanghai Jiaotong University. According to different methods for the management of proximal aortic dissection, these patients were divided into 3 groups: group A, aortic valve commissural suspension＋supracommissural replacement of the ascending aorta （SCR）,including 28 patients （20 males and 8 females，mean age 45.2±15.6 years）; group B, partial sinus remodeling+ascending aortic replacement, including 10 patients （7 males and 3 females，mean age 44.6±14.9 years）；group C, Bentall procedure,including 24 patients （17 males and 7 females，mean age 46.2±15.6 years）. Clinical outcomes were compared among the three groups. Results Six patients died peri-operatively and in-hospital mortality was 9.67% （6/62）. Fifty-four patients were followed up, and the mean follow-up time was 27.3±15.7 months. During follow up, 2 patients died, one for lung cancer and the other for unknown reason. One patient in group A underwent CT scan 6 months after surgery which showed aortic root pseudo-aneurysm. Cardiopulmonary bypass time and aortic cross-clamping time of group C were significantly longer than those of group A and group B （274±97 min vs. 194±65 min, 210±77 min, t=22.482, 30.419, P=0.002， 0.122；150±56 min vs. 97±33 min, 105±46 min, t=12.630, 17.089, P=0.000，0.034）. There was no statistical difference in mortality （t=1.352，P=0.516）, incidence of postoperative reexploration for bleeding, acute renal failure and neurological complication （t=0.855, 0.342, 2.281; P=0.652, 0.863, 0.320） among the three groups. Conclusion For patients with acute aortic dissection involving the aortic root, aortic valve commissural suspension+SCR，partial sinus remodeling＋ascending aortic replacement and Bentall procedure may be considered the surgical treatment of choice with respective advantages and disadvantages. Satisfactory clinical outcomes can be achieveed if surgical indications and procedures are properly employed.
Objective To investigate the therapeutic effects of endovascular covered stent on vertebral dissecting aneurysm and carotid-cavernous fistula (CCF). Methods From March 2006 to May 2007, Jostent coronary stent grafts were used to treat 4 patients with vertebral dissecting aneurysm and 3 patients with CCF. The patients of vertebral dissecting aneurysmwere male and 37-57 years old, the lesion was located on the left vertebral artery in 3 patients and on the right vertebral artery in 1 patient, with the primary symptoms of sudden headache and vomiting; CT scan demonstrated subarachnoid hemorrhage; and the medical history varied from 2 days to 10 years. The patients of CCF were male and 35-51 years old, the lesion was located on the left carotid artery in 2 patients and on the right carotid artery in 1 patient, with the primary symptoms of headache, lateral exophthalmos, eyeball distending pain, conjunctive hyperemia and impaired eyesight; all 3 patients got head injury 2 days to 1 month before the appearance of symptoms and 1 of them had a history of severe nosebleed; and the medical history ranged from 1 week to 2 months. Results For the patients with vertebral dissecting aneurysm, complete obl iteration of aneurysms was achieved, the circulations of the vertebral artery, the adjacent posterior inferior cerebellar artery and the adjacent anterior inferior cerebellar artery were smooth, no compl ications relative to operation occurred, and no recurrence of symptoms and intracranial rehaemorrhagia were observed during the follow-up period of 8 months-2 years. For the patients with CCF, the fistula were completely obl iterated, the circulation of carotid artery was smooth, the exophthalmus and conjunctiva hyperemia were improved obviously 3 days after operation, the eyesight of patient was improved at different levels over the follow-up period of 1-3 months. Conclusion Endovascular covered stent is a new and useful tool for the treatment of vertebral dissecting aneurysm and CCF .