Interval Of Circulatory Arrest Research Articles

Early Outcomes After Thoracoabdominal Aortic Aneurysm Repair With Hypothermic Circulatory Arrest

A variety of intraoperative strategies are currently used for organ protection during open operations on the thoracoabdominal aorta. We report our experience with cardiopulmonary bypass and hypothermic circulatory arrest as the primary modality for organ protection, focusing on the early outcomes. During a 30-year interval, 285 patients underwent thoracoabdominal aortic aneurysm repair with the use of cardiopulmonary bypass with an interval of circulatory arrest (72 Crawford extent I, 107 extent II, 104 extent III, and 2 extent IV). Degenerative aneurysms were present in 72.6% and aortic dissections in 26.4% of patients. Emergent operations for rupture or acute dissection were required in 6.7% of the patients. Thirty-day mortality was 7.4% and was highest for the Crawford extent II and extent III patients (10.3% and 6.7%, respectively). Permanent paralysis or paraplegia occurred in 15 patients (5.3%). The rates were highest for the extent II and extent III patients (6.5% and 6.7%, respectively). Cerebrospinal fluid drainage had no impact on the development of spinal cord injury, and implantation of intercostal/lumbar arteries had a protective effect only in patients with extent II repair. Stroke occurred in 4.2% of patients and renal failure that required dialysis occurred in 6.2%. One-year actual survival was 90.4%. Our extended experience with this technique confirms its safety and effectiveness when used on a routine basis. The rates of spinal cord injury and permanent renal failure are among the lowest reported in the literature. Particularly favorable outcomes were observed in younger patients and patients undergoing elective operations.

Repair of Extensive Thoracoabdominal Aortic Aneurysm with a Tetrafurcate Graft: Midterm Results of 63 Cases

The objective is to present a method for maintaining the spinal cord blood supply and our midterm results for using a tetrafurcate graft in extensive thoracoabdominal aortic aneurysm (TAAA) repair. From August 2003 to October 2007, we used a tetrafurcate graft to perform repairs to TAAAs of Crawford extent II in 63 consecutive patients. The mean age of this group of patients was 39.98 +/- 10.62 years, and 46 (73%) of them were male. All of the procedures were performed under profound hypothermia with a short interval of circulatory arrest. T6 to T12 intercostal arteries were reconstructed as a "neo-intercostal artery" (N-IA) and were connected to an 8-mm sidearm of the graft to maintain the spinal cord blood supply. Visceral arteries were joined into a patch and were anastomosed to the end of the main graft. The left renal artery was anastomosed to an 8-mm sidearm or joined to the patch. The other 10-mm sidearms were anastomosed to iliac arteries. With 100% follow-up, the early-mortality rate was 7.94%. The incidence of cerebral complications was 9.52%. Temporary paraplegia was observed in 2 patients, and paraparesis occurred in 1 patient. Pulmonary complication was the most common morbidity in this group (25.40%). Two patients with Marfan syndrome had N-IA artery pseudoaneurysms during follow-up. The mean survival time of this group was 50.64 +/- 2.13 months, with survival rates of 92.06% after 1 year, 88.38% after 2 years, and 86.11% after 3 years. The N-IA may play an important role in spinal cord protection, and N-IA pseudoaneurysm should be avoided in Marfan syndrome patients. The use of a tetrafurcate graft is a reliable method for TAAA repair, with satisfactory midterm results.

Hypothermic circulatory arrest for repair of injuries of the thoracic aorta and great vessels

Traumatic great vessel injuries are frequently lethal events. Expedient diagnosis and prompt repair by clamping and replacing the affected segment of aorta (often with left-heart bypass) can salvage many patients. Rarely, due to the location of the injury or delayed presentation, standard techniques cannot be used and hypothermic circulatory arrest (HCA) is required for access, exposure and repair. The results of surgical reconstruction of acute and chronic traumatic thoracic vascular injuries under these circumstances are not well described. We reviewed all operations on the great vessels at our institution over a 16-year period that had a traumatic etiology and used HCA. Fourteen cases were identified (10 male, 4 female, age 46+/-4 years), arising from three acute and eleven remote traumatic events. All repairs were performed with cardiopulmonary bypass (mean CPB time was 155+/-13 min), deep hypothermia, and an interval of circulatory arrest (mean circulatory arrest interval 31+/-4 min). One patient died in the perioperative period from a stroke (7% 30-day mortality). Another patient exsanguinated from a recurrent pseudoaneurysm 3 months post-repair. No patient developed paraplegia. HCA can be a useful adjunct in managing complex post-traumatic great vessel injuries. Acute injuries of the ascending aorta and transverse arch usually require this technique, but HCA also offers a safe way to manage repair of the descending thoracic aorta when proximal aortic control is compromised.

Hypothermic cardiopulmonary bypass and circulatory arrest for operations on the descending thoracic and thoracoabdominal aorta

Background Hypothermic cardiopulmonary bypass with circulatory arrest is an important adjunct for operations on the distal aortic arch, the descending thoracic, and the thoracoabdominal aorta. The safety and efficacy of this technique when compared with other adjuncts (ie, simple aortic clamping, partial cardiopulmonary bypass, regional hypothermia) is not clearly established. Methods One hundred and ninety-two patients (age range, 20 to 83 years) with descending thoracic or thoracoabdominal aortic disease had resection and graft replacement of the involved aortic segments using hypothermic cardiopulmonary bypass and intervals of circulatory arrest (mean, 38 minutes). The technique was used when the location and severity of disease precluded placement of clamps on the proximal aorta (31 patients) or (in 161 patients) when extensive thoracic (47) or thoracoabdominal (114) aortic disease was present, and the risk for development of spinal cord ischemic injury was judged to be increased. Lower intercostal and lumbar arteries were attached separately to the aortic graft in 101 of the 161 patients (63%) who had extensive aortic replacement. No other adjuncts for spinal cord protection were used. Results The 30-day mortality was 6.8% (13 patients). It was 40% (8 of 20) for patients having emergent operations (acute aortic dissection or rupture) and 2.9% (5 of 172) for all others ( p < 0.001). The 90-day mortality was 12.5% (24 patients). Paraplegia occurred in 4 and paraparesis in 1 (full recovery) of the 186 operative survivors whose lower limb function could be assessed postoperatively (2.7%). Among the 109 survivors with thoracoabdominal aortic disease, early paraplegia occurred in 1 of 36 with Crawford extent I, 0 of 42 with extent II, and 2 of 31 with extent III disease. One patient (extent II) developed paraplegia on the 9th postoperative day after a hypotensive episode. None of the 47 patients with aortic dissection developed paralysis. Among the 186 operative survivors, renal dialysis was required in 4 patients (2.2%), prolonged inotropic support in 18 (10%), reoperation for bleeding in 9 (5%), mechanical ventilation (≥ 48 hours) in 64 (34%), and tracheostomy in 17 (9%). Four patients (2%) sustained a stroke. Conclusions Hypothermic cardiopulmonary bypass with circulatory arrest provides safe and substantial protection against paralysis and renal, cardiac, and visceral organ system failure that equals or exceeds that of other currently used techniques but without the need of other adjuncts.

Safety and efficacy of hypothermic cardiopulmonary bypass and circulatory arrest for operations on the descending thoracic and thoracoabdominal aorta

Background. Hypothermic cardiopulmonary bypass with circulatory arrest is an important adjunct for operations on the distal aortic arch and the descending thoracic and thoracoabdominal aorta. Its safety and efficacy compared with other techniques (eg, simple aortic clamping, partial cardiopulmonary bypass, and regional hypothermia) are not clearly established. Methods. One hundred sixty-one patients (ranging from 20 to 83 years old) with descending thoracic or thoracoabdominal aortic disease had resection and graft replacement of the involved aortic segments using hypothermic cardiopulmonary bypass usually with intervals of circulatory arrest (mean interval, 38 minutes). Results. The 30-day mortality rate was 6.2% (10 patients). It was 41% (7 of 17) for patients having emergent operations (rupture or acute dissection) and 2.1% (3 of 144) for all other patients ( p < 0.001). The 90-day mortality rate was 11.8% (19 patients). Paraplegia occurred in 4 and paraparesis in 1 of the 156 operative survivors whose lower limb function could be assessed postoperatively (3.2%). Among the 91 survivors with thoracoabdominal aortic disease, early paraplegia occurred in 1 of 33 patients with Crawford type I disease, 0 of 34 with type II disease, and 2 of 24 with type III disease. One patient (type II disease) had development of paraplegia on the tenth postoperative day. None of the 50 patients with aortic dissection experienced paralysis. Renal dialysis was required in 4 (2.5%) of the 157 operative survivors, prolonged inotropic support (> 48 hours) in 17 (11%), reoperation for bleeding in 8 (5%), mechanical ventilation (> 48 hours) in 31 (20%), and tracheostomy in 13 (8%). Three patients (1.9%) sustained a stroke. Conclusions. Hypothermic cardiopulmonary bypass provides safe and substantial protection against paralysis and renal, cardiac, and visceral organ system failure that equals or exceeds that of other currently used techniques but without the need of other adjuncts.

Hypothermic cardiopulmonary bypass for spinal cord protection: rationale and clinical results

Background. Hypothermic cardiopulmonary bypass with or without circulatory arrest has been used successfully for the treatment of complex aneurysms of the descending thoracic and thoracoabdominal aorta. Hypothermia has a protective effect on spinal cord function, and its use has been associated with a low incidence of paraplegia in traditionally high-risk patients. Experimentally, the protective effect of hypothermia has been related to amelioration of excitotoxic injury by reduction of neurotransmitter release and to inhibition of delayed apoptotic cell death. Methods. During a 12-year period, 114 patients with descending thoracic or thoracoabdominal aortic disease underwent replacement of the involved aortic segments using hypothermic cardiopulmonary bypass and intervals of circulatory arrest. Results. The hospital mortality was 8% (9 patients). Paraplegia occurred in 2 and paraparesis in 1 of the 108 patients whose lower limb function was assessed postoperatively (2.8%). None of 40 patients with aortic dissection and none of the last 81 patients in the series developed paralysis. Conclusions. Our experience with hypothermic cardiopulmonary bypass and circulatory arrest confirms that hypothermia provides substantial protection against paraplegia, and it allows complex operations on the descending thoracic and thoracoabdominal aorta to be performed with acceptable mortality.

Hypothermic bypass and circulatory arrest for operations on the descending thoracic and thoracoabdominal aorta

Hypothermic cardiopulmonary bypass with intervals of circulatory arrest is a useful adjunct during operations on the descending thoracic aorta and distal aortic arch when severe aortic disease precludes placement of clamps on the aorta. Hypothermia also has a marked protective effect on spinal cord function during periods of aortic occlusion. Fifty-one patients (age range, 22 to 79 years) with descending thoracic or thoracoabdominal aortic disease had resection and graft replacement of the diseased aortic segments using hypothermic cardiopulmonary bypass and intervals of circulatory arrest in situations where the location, extent, or severity of disease precluded placement of clamps on the proximal aorta (8 patients) or (in 43 patients) when extensive thoracic (11) or thoracoabdominal (32) aortic disease was present and the risk for development of spinal cord ischemic injury and renal failure was judged to be increased. Patent intercostal (below T-6) and upper lumbar arteries were attached to the graft whenever possible. Thirty-day mortality was 9.8% (5 patients). Paraplegia occurred in 2 and paraparesis in 1 of the 46 30-day survivors (6.5%). Among the 27 operative survivors with thoracoabdominal aneurysms, paraplegia occurred in 1 of 12 with Crawford type I (8%), 0 of 10 with type II, and 1 of 5 with type III aneurysms (20%). Paraplegia occurred in none of the 12 patients with aortic dissection and in 2 of the 15 patients with degenerative aneurysms. Renal failure requiring dialysis occurred in 1 (2.2%) of the 46 30-day survivors. Hypothermic circulatory arrest is a valuable adjunct for the treatment of complex aortic disease involving the aortic arch and thoracoabdominal aorta. In patients with thoracoabdominal aneurysms, its use has been associated with a low incidence of renal failure and an incidence of paraplegia/paraparesis in traditionally high-risk subsets (type I and II aneurysms, aortic dissection), which may be less than that observed with other surgical techniques.