Beneficial effect of the oxygen free radical scavenger amifostine (WR-2721) on spinal cord ischemia/reperfusion injury in rabbits

<p>Abstract</p> <p>Background</p> <p>Paraplegia is the most devastating complication of thoracic or thoraco-abdominal aortic surgery. During these operations, an ischemia-reperfusion process is inevitable and the produced radical oxygen species cause severe oxidative stress for the spinal cord. In this study we examined the influence of Amifostine, a triphosphate free oxygen scavenger, on oxidative stress of spinal cord ischemia-reperfusion in rabbits.</p> <p>Methods</p> <p>Eighteen male, New Zealand white rabbits were anesthetized and spinal cord ischemia was induced by temporary occlusion of the descending thoracic aorta by a coronary artery balloon catheter, advanced through the femoral artery. The animals were randomly divided in 3 groups. Group I functioned as control. In group II the descending aorta was occluded for 30 minutes and then reperfused for 75 min. In group III, 500 mg Amifostine was infused into the distal aorta during the second half-time of ischemia period. At the end of reperfusion all animals were sacrificed and spinal cord specimens were examined for superoxide radicals by an ultra sensitive fluorescent assay.</p> <p>Results</p> <p>Superoxide radical levels ranged, in group I between 1.52 and 1.76 (1.64 ± 0.10), in group II between 1.96 and 2.50 (2.10 ± 0.23), and in group III (amifostine) between 1.21 and 1.60 (1.40 ± 0.19) (p = 0.00), showing a decrease of 43% in the Group of Amifostine. A lipid peroxidation marker measurement ranged, in group I between 0.278 and 0.305 (0.296 ± 0.013), in group II between 0.427 and 0.497 (0.463 ± 0.025), and in group III (amifostine) between 0.343 and 0.357 (0.350 ± 0.007) (p < 0.00), showing a decrease of 38% after Amifostine administration.</p> <p>Conclusion</p> <p>By direct and indirect methods of measuring the oxidative stress of spinal cord after ischemia/reperfusion, it is suggested that intra-aortic Amifostine infusion during spinal cord ischemia phase, significantly attenuated the spinal cord oxidative injury in rabbits.</p

Current trends in cannulation and neuroprotection during surgery of the aortic arch in Europe†‡

OBJECTIVES To conduct a survey across European cardiac centres to evaluate the methods used for cerebral protection during aortic surgery involving the aortic arch. METHODS All European centres were contacted and surgeons were requested to fill out a short, comprehensive questionnaire on an internet-based platform. One-third of more than 400 contacted centres completed the survey correctly. RESULTS The most preferred site for arterial cannulation is the subclavian-axillary, both in acute and chronic presentation. The femoral artery is still frequently used in the acute condition, while the ascending aorta is a frequent second choice in the case of chronic presentation. Bilateral antegrade brain perfusion is chosen by the majority of centres (2/3 of cases), while retrograde perfusion or circulatory arrest is very seldom used and almost exclusively in acute clinical presentation. The same pumping system of the cardio pulmonary bypass is most of the time used for selective cerebral perfusion, and the perfusate temperature is usually maintained between 22 and 26°C. One-third of the centres use lower temperatures. Perfusate flow and pressure are fairly consistent among centres in the range of 10-15 ml/kg and 60 mmHg, respectively. In 60% of cases, barbiturates are added for cerebral protection, while visceral perfusion still receives little attention. Regarding cerebral monitoring, there is a general tendency to use near-infrared spectroscopy associated with bilateral radial pressure measurement. CONCLUSIONS These data represent a snapshot of the strategies used for cerebral protection during major aortic surgery in current practice, and may serve as a reference for standardization and refinement of different approache

A practical tool to control bleeding during sternal reentry for pseudoaneurysm of the ascending aorta

WOS: 000181431100069PubMed ID: 12645750Big pseudoaneurysms of the ascending aorta after a previous thoracic operation are rare and represent a surgical challenge. Because the rupture during sternal reentry occurs before the clamp-control of the distal ascending aorta, it is essential to control the bleeding until the adhesions are released in order to place the sternal retractor. We report the use of Foley catheter with a malleable guidewire to control the bleeding from the defect in the ascending aorta causing a pseudoaneurysm in case of a limited access. (C) 2003 by The Society of Thoracic Surgeons

Perigraft to right atrial shunt by using autologous pericardium for control of bleeding in acute type A dissections

WOS: 000178452500024PubMed ID: 12400747Background. We report our experience with creating a perigraft to right atrial fistula by using autologous pericardium to control the inaccessible bleeding after aortic root repair in patients with acute type A aortic dissection. Methods. Between 1994 and 2001, perigraft to right atrial fistula was used in 7 of 109 patients (mean age; 55 years) who underwent emergency operation for acute type A dissections. A chamber around the aortic graft was created by suturing a patch of pericardium to the right ventricular wall inferiorly, to the pulmonary artery medially, to the Teflon felt at the distal aortic anastomosis or innominate vein superiorly, and to the superior vena cava and right atrium laterally. A large stab wound was created on the medial aspect of the right atrium. The perigraft space was then closed expeditiously. Results. None of these patients required reexploration for bleeding and they were discharged from the hospital without complications. The average blood and fresh frozen plasma requirement was 3.4 +/- 0.9 and 2.7 +/- 0.7, respectively. All underwent echocardiographic examination before discharge and no perigraft to right atrial shunt was detected. Conclusions. If intractable bleeding is encountered after the administration of protamine and thrombotic agents and a discrete bleeding site can not be found, then a perigraft to right atrial fistula using autologous pericardium can be created as a last resort. It provides primary and definite sternal closure and avoids the detrimental effects of a second pump run and continued bleeding

Analysis of perioperative risk factors in mortality and morbidity after modified Bentall operation

WOS: 000175657100008PubMed ID: 12025902The objective of the present study was to determine the risk factors for operative and short-term mortality, and morbidity after a Bentall operation, Between July 1994 and February 2001, 86 consecutive patients (70 males) Underwent a modified Bentall operation at our hospital. The aortic pathology was acute aortic dissection in 12 (14%), chronic dissection in 9 (10.5%) and degenerative aneurysm in 65 (75.6%). Mean age was 48 +/- 15 years. Eleven preoperative, 8 intraoperative and 6 postoperative variables of these patients were retrospectively analyzed using univariate and multivariate logistic regression analysis. Six patients died in the hospital (6.9%) and 2 died within four months after being discharged from the hospital. Mean follow-up time was 33 23 months (2 months to 8 years). The survival rate among hospital survivors was 88% at 3 years and 77% at 6 years. Univariate predictors of in-hospital and short-term mortality were the presence of aortic valve calcification, stenotic aortic valves, renal failure, and cardiac failure after the operation. Multivariate analysis revealed no independent risk factors. Risk factors for morbidity were etiology of acute dissection, use of circulatory at-rest, transfusion of blood and fresh frozen plasma more than 2 units each, cross clamp and cardiopulmonary bypass times (exceeding 90 and 140 minutes, respectively), and performing concomitant procedures. Modified Bentall procedures are safe in general. Meticulous dissection, careful handling and positioning of the coronary buttons are of paramount importance in patients with stiff aortic root since technical errors are more likely to occur

Adverse effects of cell saver in patients undergoing ruptured abdominal aortic aneurysm repair

WOS: 000177802500008PubMed ID: 12089630A retrospective analysis of 56 patients undergoing ruptured abdominal aortic aneurysm (AAA) repair was performed to find out if cell saver had any impact on postoperative morbidity and mortality. All patients but one were male. The mean age was 68 +/- 8 years (35-85 years). Cell saver was used in 40 patients (CS group) and was not used in 16 patients (NCS group). We compared the incidences of respiratory, renal, and gastrointestinal complications; reoperation; transfusion requirement; length of hospital stay; and mortality between the groups. This study demonstrated that intraoperative cell saver usage significantly increased the incidence of respiratory complications and the need for blood and fresh frozen plasma transfusion, and prolonged the hospital stay in patients with ruptured AAA, but did not have any impact on mortality. Postoperative complications were more prominent in patients who received greater than or equal to3000 mL cell saver blood