Spinal fluid dynamics during thoracic- and thoracoabdominal aortic surgery.

AIM: The intention was to investigate cerebrospinal fluid pressure (CSFP) and volume of cerebrospinal fluid (CSF) drained during and after thoracic- and thoracoabdominal aneurysm repair. The findings were related to the occurrence of postoperative neurologic deficits. METHODS: Twenty-nine patients (12 with thoracic and 17 with thoracoabdominal aortic aneurysm) were operated without shunting or extracorporeal circulation. For monitoring of CSFP an intrathecal catheter was placed in all patients. The volume of CSF withdrawn intraoperatively, on the day of operation as well as on the 1st and 2nd postoperative day was recorded. RESULTS: Twenty-six patients had no postoperative neurologic sequelae. One patient had postoperative paraplegia while 2 had paraparesis. The three patients with neurologic sequelae had higher CSFP intraoperatively than those without neurologic symptoms (P=0.04). Median CSFP during aortic cross-clamping was 19 mmHg and 10 mmHg and the median volumes of CSF drained on the day of operation 210 and 85 mL in the two groups, respectively. There was a significant positive correlation between CSFP and central venous pressure. CONCLUSIONS: A higher intraoperative CSFP was observed in patients with neurologic sequelae following thoracic- and thoracoabdominal aneurysm repair. Further, there was a tendency of higher volumes of CSF drained in this group of patients. Although, the series is too small to allow firm conclusions, it supports the view that CSFP monitoring and drainage is beneficial during thoracic- and thoracoabdominal aneurysm repair.

Recovery following treatment of descending thoracic aortic disease. A comparison between endovascular repair and open surgery.

AIM: The aim of this study was to compare the postoperative course in patients treated by endovascular repair (endo) with patients treated by open surgery (open) for descending thoracic aortic disease. METHODS: Twenty-five patients treated with stent grafting for aneurysmal disease or type B dissection were compared with 35 historical controls treated by open surgery. Stay in the intensive care unit, need for artificial ventilation and to where the patient had been discharged, were noted. Pain medication, use of nasogastric tube, time until total oral nutrition, mobilization and the patients' mental condition in the postoperative period, were studied in the patients charts and the nursing reports. RESULTS: Time on the intensive care unit or intermediate care unit was median 45 h in the endo group compared with 192 h in the open group. Eighty percent of the patients in the endo group were discharged directly to their homes in contrast to 23% after open surgery. In the endo group 67% of the patients started oral nutrition on the 1st postoperative day compared to 10% in the open group. There was a significantly faster mobilization in the endo group. CONCLUSIONS: There was a significantly shorter recovery after stent grafting for descending thoracic aortic disease compared to patients operated with open surgical technique.

Changes in hemodynamics and acid-base balance during cross-clamping of the descending thoracic aorta. A study in patients operated on for thoracic and thoracoabdominal aortic aneurysm.

AIM OF THE STUDY: In the clinical situation there is discrepancy between various investigations regarding the cardiac response of thoracic aortic cross-clamping. The aim was therefore to investigate the hemodynamic response and blood gases during proximal aortic cross-clamping (XC) in patients operated for descending thoracic and thoracoabdominal aortic aneurysm without circulatory support. PATIENTS AND METHODS: Altogether 51 patients operated on for thoracoabdominal (n=31) or descending thoracic aortic aneurysm (n=20) were included in the investigation. All patients were operated with aortic XC, but no circulatory support was applied. Hemodynamic variables and blood gases were recorded before and during XC. RESULTS: A significant increase in cardiac output during XC from 4.7 to 6.0 liters/min was observed (p<0.01). There was a similar percentual increase in heart rate and also the proximal systolic blood pressure increased. A metabolic acidosis occurred during XC. CONCLUSION: Cardiac output was significantly increased during XC in patients operated on for thoracoabdominal or descending thoracic aneurysm using direct aortic XC without circulatory support. Simultaneously, the heart rate was increased and there was a hyperdynamic circulatory state proximal to the aortic clamp. Redistribution of the blood volume in addition to catecholamine release may be responsible for the observed changes. These observations may influence the selection of operative strategy for some of these patients.

A strategy for treatment of type III and IV thoracoabdominal aortic aneurysm.

The aim of this study was to describe the results of resection and graft replacement for type III and IV thoracoabdominal aortic aneurysm repair. In this retrospective study, 27 patients underwent resection and graft replacement for type III (10) or type IV (17) thoracoabdominal aortic aneurysms. Nine patients had rupture, 12 were symptomatic, and 6 were operated on electively. The "clamp-and-sew" technique was applied in six cases. In 12 patients with type IV aneurysm the proximal part of the vascular graft was beveled, including the orifices of the celiac, superior mesenteric, and one or both renal arteries in the proximal anastomosis. Finally, eight patients underwent surgical application of a shunt for perfusion of the celiac and superior mesenteric arteries. One patient was treated with a combination of open and endovascular surgery. There were four early deaths (14.8%), all following operations for rupture, which represents a 45% mortality rate in this subgroup of patients. Two patients with type III aneurysm had postoperative paraparesis. One was symptomatic whereas the other was operated on electively. Excluding the patients with rupture, the accumulated 5-year survival rate was 65%. These results indicate that direct cross-clamping of the aorta gives limited time for performing the necessary anastomoses without inducing mesenteric ischemia. Inclusion of the orifices of the visceral arteries in the upper anastomosis is a feasible method during surgery for type IV aneurysms. Finally, shunting of the celiac and the superior mesenteric arteries seems to be useful, especially during surgery for type III aneurysms.

Shunting of the coeliac and superior mesenteric arteries during thoracoabdominal aneurysm repair.

OBJECTIVES: To describe our experience with shunting of the coeliac and superior mesenteric arteries during thoracoabdominal aneurysm repair. DESIGN: Retrospective study. MATERIAL: Eight patients undergoing resection and graft replacement of Crawford type III (5) and type IV (3) thoracoabdominal aortic aneurysms were included in this series. One patient had rupture, four were symptomatic and three were operated on electively. METHODS: A vascular graft with a sidearm was applied for the reconstructions. A T-shunt was connected to the sidearm. Following completion of the proximal anastomosis the shunt was inserted into the coeliac and superior mesenteric arteries. The anastomoses to these arteries and the renal arteries were then completed. Finally the distal anastomosis was performed. RESULTS: There was no early mortality (30 days). One patient had postoperative paraparesis, but recovered quite well. Reoperation became necessary due to sigmoid necrosis in one patient and due to haemorrhage in another. During the follow-up period four patients died but the other patients are alive between 3 and 8 years after surgery. CONCLUSION: The application of shunting of the superior mesenteric and coeliac arteries during thoracoabdominal aortic surgery is feasible and the results have been acceptable. Further investigation of the optimal blood flow needed to avoid intestinal ischaemia in a larger series of patients is desirable.