Effects of deep hypothermic circulatory arrest on outcome after resection of ascending aortic aneurysm

BACKGROUND: Aneurysm of the ascending aorta is a common finding especially in patients with aortic valve diseases. The aim of this study was to analyze early and midterm outcome in patients operated on for aneurysm of the ascending aorta with or without the use of deep hypothermic circulatory arrest (DHCA). METHODS: Between January 1996 and December 2000, 133 of 410 patients with thoracic aortic pathology were operated on for an aortic aneurysm limited mainly to the ascending aorta. Early and midterm outcomes were assessed and quality of life (QOL) evaluated using the Short-Form 36 Health Survey Questionnaire (SF-36). RESULTS: Sixty patients (group 1) were operated on with DHCA and 73 patients (group 2) without DHCA. In-hospital mortality was identical in both groups (9.6% versus 6.7%; p = not significant) whereas postoperative transient neurologic events were significantly more frequent in group 1 (6.7% versus 0%; p < 0.05). Midterm clinical outcome was not different between groups but QOL showed significant impairment in daily functional physical and emotional activity in group 1 patients compared with group 2 and an age-matched standard population. CONCLUSIONS: The risk of transient neurologic complications is significantly increased with the use of DHCA and QOL is impaired without benefits in the long-term outcome especially among older patients.     

Temporary neurological dysfunction after surgery of the thoracic aorta: a predictor of poor outcome and impaired quality of life

BACKGROUND: Transient neurological dysfunction (TND) consists of postoperative confusion, delirium and agitation. It is underestimated after surgery on the thoracic aorta and its influence on long-term quality of life (QoL) has not yet been studied. This study aimed to assess the influence of TND on short- and long-term outcome following surgery of the ascending aorta and proximal arch. METHODS: Nine hundred and seven patients undergoing surgery of the ascending aorta and the proximal aortic arch at our institution were included. Two hundred and ninety patients (31.9%) underwent surgery because of acute aortic dissection type A (AADA) and 617 patients because of aortic aneurysm. In 547 patients (60.3%) the distal anastomosis was performed using deep hypothermic circulatory arrest (DHCA). TND was defined as a Glasgow coma scale (GCS) value <13. All surviving patients had a clinical follow up and QoL was assessed with an SF-36 questionnaire. RESULTS: Overall in-hospital mortality was 8.3%. TND occurred in 89 patients (9.8%). As compared to patients without TND, those who suffered from TND were older (66.4 vs 59.9 years, p<0.01) underwent more frequently emergent procedures (53% vs 32%, p<0.05) and surgery under DHCA (84.3% vs 57.7%, p<0.05). However, duration of DHCA and extent of surgery did not influence the incidence of TND. In-hospital mortality in the group of patients with TND compared to the group without TND was similar (12.0% vs 11.4%; p=ns). Patients with TND suffered more frequently from coronary artery disease (28% vs 20.8%, p=ns) and were more frequently admitted in a compromised haemodynamic condition (23.6% vs 9.9%, p<0.05). Postoperative course revealed more pulmonary complications such as prolonged mechanical ventilation. Additional to their transient neurological dysfunction, significantly more patients had strokes with permanent neurological loss of function (14.6% vs 4.8%, p<0.05) compared to the patients without TND. ICU and hospital stay were significantly prolonged in TND patients (18+/-13 days vs 12+/-7 days, p<0.05). Over a mean follow-up interval of 27+/-14 months, patients with TND showed a significantly impaired QoL. CONCLUSION: The neurological outcome following surgery of the ascending aorta and proximal aortic arch is of paramount importance. The impact of TND on short- and long-term outcome is underestimated and negatively affects the short- and long-term outcome.     

The incidence of transient neurologic dysfunction after ascending aortic replacement with circulatory arrest

BACKGROUND: Transient neurologic dysfunction (TND) namely postoperative confusion, delirium, and agitation after aortic operation, particularly after deep hypothermic circulatory arrest (DHCA), remains an underestimated adverse event in the early outcome of these patients. Although no influence on long-term outcome has been reported so far, this entity markedly affects the early outcome and leads to prolonged intensive care unit and hospital stay. METHODS: Between January 1997 and January 2003, 160 consecutive patients (130 type A dissections [81%] and 30 elective atherosclerotic aneurysms [19%]) had surgical repair with DHCA for a thoracic aortic aneurysm limited to the ascending aorta. From those, 40 patients (25%) underwent DHCA alone, whereas in 13 patients (8%) antegrade cerebral perfusion and in 103 patients (64%) retrograde cerebral perfusion was used for further brain protection. RESULTS: The overall incidence of TND was 18% (28 of 160) with a significant association between duration of circulatory arrest and the incidence of TND (13.8% in DHCA < 30 minutes versus 37.9% in DHCA > 40 minutes; p < 0.05). Furthermore the severity of TND was directly associated with the duration of circulatory arrest and age. In contrast, however, the use of retrograde cerebral perfusion had no influence on the incidence of TND, (p < 0.05). Intensive care unit stay as well as hospital stay were prolonged in the patients with TND (intensive care unit 14.3 +/- 14.2 days versus 10.8 +/- 13.7 days, p < 0.05; hospital stay 15.6 +/- 10.1 days versus 11.4 +/- 7.9 days, p < 0.05). CONCLUSIONS: Duration of DHCA, regardless of whether retrograde cerebral perfusion was used, was the most important predictor of the incidence of transient neurologic dysfunction in patients who had replacement of the ascending thoracic aorta. The occurrence of TND leads to impaired functional recovery as well as prolonged intensive care unit and hospital stay.     

不同脑保护方法下主动脉术后脑脊髓液S100β及IL-6的变化

目的通过对主动脉手术围手术期脑脊髓液生化指标变化的比较,评价两种不同脑保护方法的效果。方法2004年11月至2005年4月接受手术治疗的主动脉瘤患者14例,其中I型主动脉夹层11例,Ⅲ型主动脉夹层2例,假性胸腹主动脉瘤1例。在单纯深低温停循环（DHCA）下行胸降主动脉替换5例（DHCA组）;在DHCA结合选择性顺行脑灌注（ASCP）下行主动脉弓部置换9例（ASCP组）。于术前及术后0、6、12、24、48和72h检测脑脊髓液S10013蛋白（S100β）及白细胞介素6（IL-6）水平。结果ASCP组停循环时间长于DHCA组。两组脑脊髓液中S100β及IL-6的术前水平无显著差别。两组S100β于术后12h达到峰值;术后6—72h各时间点两组S100β水平差异有统计学意义（P〈0．05）。两组IL-6分别于术后12h和0h达到峰值;术后6h及12h两组IL-6水平差异有统计学意义（P〈0．05）。结论在两种脑保护方法下主动脉手术中发生的缺氧性脑损伤均属轻型。DHCA结合单侧ASCP具有比单纯DHCA更好的脑保护效果,围手术期的脑损伤较轻。     

Aortic arch replacement with proximal first technique.

BACKGROUND: Deep hypothermic circulatory arrest (DHCA) without retrograde cerebral perfusion (RCP) has a strict time limit. We modified a surgical technique for anastomosis to shorten the period of DHCA and unilateral cerebral perfusion (UCP). METHODS: Between March 1993 and August 2001, retrospective analysis was done on 23 consecutive patients, who underwent aortic arch replacement with branches. The patients were divided into two groups: DHCA group and UCP group. The DHCA group, in which DHCA alone and without additional cerebral perfusion was performed, comprised of nine patients. Proximal aortic anastomosis was performed first during systemic cooling; then both the brachiocephalic artery and left carotid artery were reconstructed with the branches of the artificial graft during circulatory arrest; thereafter, cerebral and coronary perfusions were resumed. The UCP group, in which DHCA was not used but right hemisphere perfusion during deep hypothermia was performed when the origin of brachiocephalic artery was safely clamped, consisted of 14 patients. RESULTS: Mean time of DHCA was 18.8+/-4.2 minutes and that of right hemisphere perfusion time was 11.0+/-3.8 minutes, respectively. Twenty-one patients survived the surgery (91.3%), and two (8.7%) died during hospitalization. Transient cerebral complication occurred in four patients in the DHCA group and all recovered. Logistic regression analysis revealed that DHCA was the only parameter to significantly influence temporary neurological dysfunction. There was no other significant difference between the two groups. CONCLUSION: With our modified and simple surgical technique for aortic arch repair, we were able to successfully shorten the DHCA time and right hemisphere perfusion time. However, because DHCA was the only parameter to significantly influence temporary neurological dysfunction, some form of continuous cerebral perfusion at deep hypothermia may be a safer method to preserve cerebral function.     

经上腔静脉逆行灌注脑保护在主动脉瘤手术中的应用

目的　探讨在主动脉瘤手术中应用经上腔静脉逆行灌注的脑保护效果。　方法　 65例主动脉瘤患者分 2组 ,15例采用深低温停循环 (DHCA) ,5 0例经上腔静脉逆行灌注 (RCP)进行脑保护。术中比较 2组患者不同时间颈内静脉的血乳酸含量 ,对部分RCP患者测定了灌注血和回流血的流量分布 ,以及灌注血和回流血的氧含量。　结果　DHCA组停循环时间为 10 0～ 63 0min ,平均(3 5 9± 18 8)min ;RCP组为 16 0～ 81 0min ,平均 (45 5± 17 2 )min。术后至清醒时间DHCA组为4 4～ 9 4h ,平均 (7 1± 1 6)h ;RCP组 2 0～ 9 0h ,平均 (5 4± 2 2 )h。DHCA组手术死亡 3例 ,RCP组死亡 1例 ;术后神经系统并发症DHCA组 3例 (死亡 2例 ,成活 1例 ) ,RCP组 1例 (存活 )。手术总成功率和神经系统并发症发生率RCP组分别为 96%和 2 % ,DHCA组为 67%和 2 0 % (P <0 0 5 )。RCP组再灌注期间颈内静脉血乳酸含量增高幅度低于DHCA组 [(4 4± 0 6)mmol/Lvs (6 2± 0 9)mmol/L ,P <0 0 1],经头臂和下腔静脉血流量测定显示约 2 0 %血液经头臂动脉回流 ,灌注血和回流血氧差9 0 0～ 13 67ml/L ,证实RCP期间脑组织有氧利用。　结论　在主动脉瘤手术中 ,应用RCP可以延长停循环的安全时限 ,是可行的脑保护方法     

Outcomes after ascending aorta and proximal aortic arch repair using deep hypothermic circulatory arrest with retrograde cerebral perfusion: analysis of 207 patients

OBJECTIVES Correction of ascending aorta and proximal aortic arch pathology with numerous surgical techniques having been proposed over the years remains a surgical challenge. This study was undertaken to identify risk factors influencing outcome after aortic arch operations, requiring deep hypothermic circulatory arrest (DHCA). METHODS Between 1993 and 2010, 207 consecutive patients were operated for ascending aorta and proximal arch correction with the use of deep hypothermic circulatory arrest with retrograde cerebral perfusion. All patients were followed up with regular out-patient clinics, transthoracic echocardiography and, when required, chest computed tomography. RESULTS There were 102 (49.3%) emergencies (acute type A dissection) and 105 (50.7%) elective cases. Mean age: 63.5?±?12?years. Mean circulatory arrest time was 25.4?±?13?min. Unadjusted analysis of factors associated with 30-day mortality revealed emergency status, preoperative hemodynamic instability, acute dissection, reoperation, increased circulatory arrest time, postoperative bleeding, postoperative creatinine levels and presence of neurological dysfunction. Multi-adjusted analysis revealed duration of circulatory arrest as the only and main factor related to death. Thirty-day mortality was 2.4% for the elective and 7.2% for emergencies cases. Survival during long-term follow-up was 93, 82 and 53% at 1, 5 and 10?years, respectively. CONCLUSIONS Ascending aorta and proximal aortic arch replacement with brief duration of deep hypothermic circulatory arrest combined with retrograde cerebral perfusion is a safe method with acceptable short- and long-tem results.     

Quality of life after interventions on the thoracic aorta with deep hypothermic circulatory arrest.

OBJECTIVE: Assessment of quality of life (QL) in patients undergoing major surgical procedures is of increasing interest. We focused on surgery of the thoracic aorta requiring deep hypothermic circulatory arrest (DHCA). Aim of this study was to assess QL after thoracic aortic surgery with DHCA, using the Short Form 36 Health Survey (SF-36) questionnaire. METHODS: Between 01/94 and 12/99 212 (59.1%) out of a total of 359 interventions on the thoracic aorta were performed under DHCA, with an early mortality of 13.7% (28 patients). During an average follow-up of 3.2+/-1.3 years, 27 patients died (15.2%) and five patients (2.8%) were lost. A total of 145 patients (81.9%) had a complete follow-up. RESULTS: 125 of the 145 SF-36 questionnaire handed out were answered correctly (86.2%). In relation to a standard population (z=0), the most important deficits were found in physical function (z=-0.53) and role limitations because of physical health (z=-0.42). Good results were found regarding the aspect of pain (z=0.28), social functioning (z=0.02) and vitality (z=-0.02). Overall QL in patients having been operated for aortic aneurysm was better than for patients with acute type A-dissection. CONCLUSION: Despite restrictions in physical functioning and role limitation because of physical health, QL in patients after interventions on the thoracic aorta with DHCA is fairly good and, for patients being operated for aortic aneurysm, comparable to an age-matched standard population. Patients having being operated electively for aortic aneurysm enjoyed a better QL than patients having been operated emergently for acute type A dissection.     

Hypothermic circulatory arrest is not a risk factor for neurologic morbidity in aortic surgery: a propensity score analysis

OBJECTIVE: Hypothermic circulatory arrest has been an important tool in aortic arch surgery, even though its use has recently been discussed controversially. We sought to clarify the role of hypothermic circulatory arrest as a risk factor for mortality and neurologic morbidity in aortic surgery by using a propensity score-matching analysis. METHODS: Five hundred eleven patients (60 +/- 13 years, 349 male patients) who underwent replacement of the ascending aorta with (n = 273) or without (n = 238) arch involvement were analyzed by means of multivariate analysis. Using propensity score matching, we identified comparable patient groups: HCA(+) group and HCA(-) group (n = 110 each). For aortic arch replacement, hypothermic circulatory arrest was used with a mean duration of 14 +/- 9 minutes: 12 +/- 7 minutes or 26 +/- 8 minutes for partial or total arch replacement, respectively. RESULTS: In the entire cohort multivariate analysis identified acute dissection and duration of cardiopulmonary bypass as significant predictors for hospital death. Predictors for stroke were acute dissection, diabetes mellitus, peripheral arterial disease, and concomitant mitral valve surgery, and predictors for temporary neurologic dysfunction were peripheral arterial disease and age. After propensity score matching, the incidence of death (HCA[+]: 0.9% vs HCA[-]: 2.7%), stroke (0% vs 1.8%, respectively), and temporary neurologic dysfunction (15.5% vs 13.6%, respectively) was comparable between the 2 groups. Multivariate analysis identified age, diabetes mellitus, peripheral arterial disease, and concomitant coronary artery bypass grafting as the independent risk factors for temporary neurologic dysfunction. CONCLUSIONS: In a standard clinical setting (hypothermic circulatory arrest of <30 minutes and nasopharyngeal temperature of <20 degrees C), hypothermic circulatory arrest constitutes no significant risk for mortality or neurologic morbidity and thus appears clinically safe. Patient-related risk factors primarily determine clinical outcome.     

Clinical application of retrograde cerebral perfusion for brain protection during surgery of ascending aortic aneurysm--a report of 50 cases

This study was designed to discuss the effects on the brain by different protective methods in ascending aortic aneurysm surgery retrospectively. Two hundred seventy-one surgeries of ascending aortic aneurysm have been done in the past 15 years. There were 65 patients with a dissecting aneurysm of the aortic arch or right arch. To protect the brain, deep hypothermic circulatory arrest (DHCA) combined with retrograde cerebral perfusion (RCP) through superior vena cava (N = 50) and simple DHCA (N = 15) were used during the procedure. Blood samples for lactic acid level from the jugular vein were compared in both groups. Perfusion blood distribution and oxygen content difference between the perfused blood and returned blood were measured in 5 and 10 of RCP patients, respectively. The DHCA time was 35.86 +/- 18.81 min (10 approximately 63 min) and DHCA + RCP time was 45.5 +/- 17.21 min (16 approximately 81 min). The resuscitation time was 7.11 +/- 1.59 h (4.4 - 9.4 h) in DHCA versus 5.43 +/- 2.15 h (2 approximately 9 h) in RCP patients. The operation death rate was 3/15 in DHCA group and 1/50 in RCP patients. Central nervous complication occurred in 3/12 of DHCA patients and 1/49 of RCP patients (p < .01). The overall survival rate was 96% (RCP) versus 67% (DHCA); the central nervous system dysfunction was 20% in DHCA versus 2% in RCP (p < .001). The blood lactic acid level increased significantly after reperfusion in DHCA than that in RCP. The measurement of blood distribution indicated that approximately 2Q% of the perfused blood returned from arch vessels. The difference of oxygen content between perfused and returned blood showed that the oxygen uptake was adequate in RCP group. The application of RCP can prolong the safety duration of circulation arrest. Continuous cerebral perfusion may maintain the brain at a cooler temperature and flush out particulate and air emboli while open anastomosis of the aortic arch to the prosthesis can be safely performed. Therefore, RCP is a preferable method for brain protection in our clinical practices.     

Therapeutic strategies for acute type A aortic dissection

We herein present the early and mid-term outcomes of therapeutic strategies for acute type A aortic dissection in our department. Subjects were 75 patients who were admitted to our department from January 2001 to October 2006. A total of 33 patients had thrombosed dissection: emergent surgery was indicated for cases in which the maximal ascending aortic diameter was > or =50 mm or when ulcer-like projection (ULP) was observed in the ascending aorta. Only 1 case of rupture-related death was observed, in a patient who had a maximal ascending aortic diameter of 52 mm and refused surgery. Although 8 patients were converted to surgery during the chronic phase, elective surgery was recommended in all cases. Surgery consisted of entry resection using open distal anastomosis under circulatory arrest at a bladder temperature of 25 degrees C, with antegrade cerebral perfusion into the 3 cervical branches of arch aorta based on bilateral axillary artery. In-hospital mortality of the 62 patients who underwent surgery was low (4.8%) and no dissection-related deaths were reported for the midterm outcomes. In addition, a low rate of cerebral infarction was observed among cases who had residual dissection of the brachiocephalic arteries after surgery. These findings demonstrate the validity of the therapeutic strategies in our department.     

Cannulation of the Extrathoracic Left Common Carotid Artery for Thoracic Aorta Operations Through Left Posterolateral Thoracotomy

The femoral artery is the usual site of arterial cannulation in thoracic aorta operations through left posterolateral thoracotomy that require cardiopulmonary bypass (CPB) with deep hypothermic circulatory arrest (DHCA). The advantage of this perfusion route is in limiting the duration of circulatory arrest. It is associated, however, with the risk of retrograde embolization or, in cases involving aortic dissection, malperfusion of vital organs. To prevent these risks, we have used the extrathoracic left common carotid artery as the perfusion route. From December 1999 to January 2003, we used cannulation of the left extrathoracic common carotid artery in 42 thoracic aorta operations through posterolateral thoracotomy with an open proximal anastomosis technique during DHCA. The indication for thoracic aortic repair was atherosclerotic ulcer in 7 cases, chronic aortic aneurysm in 18, acute type B dissection in 5, and chronic type B dissection in 12. Cannulation of the extrathoracic left common carotid artery was successful in all patients. Postoperative recovery was uneventful, with no cerebrovascular events in all cases. No cannulation-related complications were observed. One patient died from cardiac insufficiency on postoperative day 5. No peripheral neurological deficits (paraplegia or paraparesis) were observed. Postoperative complications included atrial fibrillation in five patients, reoperation to control hemorrhage in six, respiratory insufficiency in nine, and renal insufficiency in six. These results indicate that cannulation of the left extrathoracic common carotid artery is a useful, reliable method for proximal perfusion during CPB in patients undergoing repair of the descending thoracic aorta through left posterolateral thoracotomy. By providing effective perfusion of the brain, this technique can prolong safe DHCA time. Another advantage is the prevention of cerebral emboli, ensuring retrograde flow to the aortic arch.Presented at the Eighteenth Annual Meeting of the Société de Chirurgie Vasculaire de Langue Française, Toulouse, France, May 21-24, 2003.     

支架"象鼻"术治疗DeBakey Ⅰ型主动脉夹层动脉瘤

目的 探讨支架"象鼻"手术治疗DeBakey Ⅰ型主动脉夹层动脉瘤(AD)的方法和效果.方法 12例DeBakey Ⅰ型AD患者,平均年龄48.1岁.采用深低温停循环(DHCA),右腋动脉顺行灌注(SCP)脑保护,实施支架"象鼻"手术(即升主动脉和全弓置换及降主动脉腔内支架植入).结果 术后死亡1例,手术死亡率8.3%.术中体外循环时间(163.2±17.7)min,停循环时间(41.6±12.3)min.随访3～6个月,无死亡病例.结论 支架"象鼻"手术简单,停循环时间短,治疗DeBakey I型夹层主动脉瘤安全、有效.     

Perioperative outcome in adults undergoing elective deep hypothermic circulatory arrest with retrograde cerebral perfusion in proximal aortic arch repair: evaluation of protocol-based care

OBJECTIVE: The purpose of this study was to describe perioperative outcome in adults undergoing elective proximal aortic arch repair with protocol-based deep hypothermic circulatory arrest (DHCA) with retrograde cerebral perfusion (RCP). DESIGN: Retrospective and observational. SETTING: Cardiothoracic operating rooms and intensive care unit. PARTICIPANTS: Seventy-nine consecutive adults undergoing elective proximal aortic arch repair with DHCA (1999-2001). INTERVENTIONS: None. MAIN RESULTS: Average age of the patients was 64.9 years. Mean circulatory arrest time was 30.4 +/- 8.5 minutes. Perioperative mortality was 7.6%. Perioperative stroke incidence was 3.8%. Tracheal extubation was successful in 87.3% of patients within 24 hours of operation. Of the cohort, 80.8% were discharged from the intensive care unit within 72 hours of surgery. Median length of hospital stay was 7.4 days. Repeat mediastinal exploration because of bleeding occurred in 3.8% of patients. Although perioperative renal dysfunction (defined as >1.5-fold increase in plasma creatinine concentration) developed in 24.0% of patients, only 3.8% required dialysis. CONCLUSIONS: The above parameters establish a baseline incidence for major perioperative complications in adults undergoing elective DHCA with RCP for elective proximal aortic arch repair. In approaching the open aortic arch for short periods of circulatory arrest, deep hypothermia with adjunctive RCP is safe and effective.     

Does the technique of distal anastomosis influence clinical outcomes in acute type A aortic dissection?

The purpose of this study was to evaluate clinical outcomes of two different surgical techniques for the repair of acute type A dissection: open distal anastomosis under deep hypothermic circulatory arrest (DHCA) compared with distal aortic clamping on hypothermic cardiopulmonary bypass (ACPB). Between January 2000 and July 2008, 82 patients underwent DHCA and 42 had ACPB. Major morbidity, operative mortality and five-year actuarial survival were compared between groups. There were no significant differences in the preoperative characteristics. Operative mortality (17% in DHCA vs. 21% in ACPB, P=0.63), reoperation for bleeding (20% in DHCA vs. 34% in ACPB, P=0.16) and stroke rates (16 DHCA vs. 24% in ACPB, P=0.33) were comparable between the two groups. Actuarial five-year survival rates were 74% for DHCA vs. 73% for ACPB, P=0.99. No significant differences in operative mortality, major morbidity and actuarial five-year survival were observed between DHCA and ACPB. There are some practical technical advantages if the distal anastomosis is performed in an open manner. More studies are required to determine the fate of the false lumen between the two techniques.     

Cardiac surgery with deep hypothermic circulatory arrest produces less systemic inflammatory response than low-flow cardiopulmonary bypass in newborns

OBJECTIVE: We sought to compare low-flow cardiopulmonary bypass with deep hypothermic circulatory arrest in respect to the influence on the systemic inflammatory response. METHODS: Twenty-three infants weighing less than 10 kg and scheduled for repair of congenital malformations were enrolled in a randomized, controlled study. Eleven patients underwent cardiac surgery with deep hypothermic circulatory arrest (the DHCA group). Low-flow cardiopulmonary bypass was used in another 12 patients (the LF group). Interleukin 6 and 8 and anaphylatoxin C3a levels were measured 6 times perioperatively. Also, perioperative weight gain and a radiologic soft-tissue index were compared. RESULTS: All patients had an uneventful clinical course. Duration of deep hypothermic circulatory arrest was 40 +/- 4 minutes; the bypass time was significantly shorter in the DHCA group (85 +/- 8 vs 130 +/- 19 minutes). However, the duration of the operation was similar in both groups (245 +/- 30 vs 246 +/- 30 minutes). During cardiopulmonary bypass (rewarming), the concentration of C3a (3751 +/- 388 vs 5761 +/- 1688 ng/mL, mean +/- SEM) was significantly lower in the DHCA group than in the LF group. The interleukin 8 level was significantly lower, and the interleukin 6 level had a tendency to be lower in the DHCA group compared with levels in the LF group. There was less weight gain on the first postoperative day in the DHCA group (65 +/- 61 vs 408 +/- 118 g). The soft-tissue index suggested reduced edema formation in the DHCA group. CONCLUSION: Deep hypothermic circulatory arrest produces less systemic inflammatory response than low-flow cardiopulmonary bypass. In addition, there is an indication of less fluid accumulation postoperatively.     

Surgery for acute type a aortic dissection using retrograde cerebral perfusion

OBJECTIVE: We reviewed the surgical management of acute type A aortic dissection between 1989 and 1998. METHODS: Subjects were 28 consecutive patients (mean age: 61.8 +/- 10.7 years) with acute type A aortic dissection were studied. The mean duration between aortic dissection onset and surgery was 17.5 +/- 17.0 hours. In surgery, aortic pathology and flow patterns in dissected aortic channels were evaluated using transesophageal and epiaortic echo. Simple, safe combination of profound hypothermic circulatory arrest with retrograde cerebral perfusion and open aortic anastomosis was used for brain protection. Hypothermic circulatory arrest was 46.9 +/- 24.8 minutes. Aortic repair consisted in ascending aortic replacement in 5 patients, with hemiarch repair in 17, and total arch repair in 6. Intimal tears were resected in all but 2 patients. Concomitantly resuspension of the aortic valve was done in 9 and aortic root replacement in 2. RESULTS: No operative (30-day) deaths occurred, although 2 died from unrelated hepatic failure during hospitalization or late-stage pancreatic cancer in the late stage. In cerebral sequellae, 1 patient suffered a stroke and 2 patients developed temporary neurologic dysfunction. CONCLUSION: Our experience demonstrated that the simplified conjunction of hypothermic circulatory arrest with retrograde cerebral perfusion and open aortic anastomosis, associated with real-time assessment by transesophageal and epiaortic echo, is safe and useful during emergency aortic repair for acute type A aortic dissection.     

Cardiopulmonary bypass for thoracic aortic aneurysm: a report on 488 cases

Our objective was to investigate different cardiopulmonary bypass (CPB) techniques for thoracic aortic aneurysm retrospectively. Four hundred and eighty-eight patients with thoracic aortic aneurysm received surgical treatment. Total CPB was used routinely in 331 cases with ascending aortic aneurysm. When the aneurysm expanded to the aortic arch, brain protection was executed by adopting deep hypothermia circulatory arrest (DHCA) or DHCA combined with retrograde cerebral perfusion (RCP). Selected cerebral perfusion via carotid artery was used in three cases and separated upper and lower body perfusion in five cases. Left heart bypass was adopted for the surgeries of 157 cases with descending aortic aneurysm. In two of the cases, ventricular defibrillation could not be achieved, and then bypass was altered to separated upper and lower body perfusion to acquire satisfactory outcome. In the ascending aortic aneurysm group, DHCA time in the 17 patients was 10-63 minutes (mean 35.58 +/- 18.81 min), and DHCA +/- RCP time in 61 patients was 16-81 minutes (mean 43.43 +/- 17.91 min). Total mortality of aortic aneurysm surgery requiring full CPB was 5.4% (18/331), in which eight patients died in emergency operations. The total mortality of emergency operation was 11.9% (8/67). In the descending aortic aneurysm group, time of left heart bypass was 125.56 +/- 57.28 min, and the total mortality was 7% (11 of 157 patients). Three patients developed postoperative paraplegia. Techniques for extracorporeal circulation for surgery of the aorta are dependent on the nature of the disease and require a flexible approach to meet the specific anatomical challenge. The ability to alter the perfusion circuit to meet unexpected situations should be anticipated and planned for. In this series, we have varied our approach to perfusion techniques as required with acceptable outcome data as compared to the international literature.     

升主动脉和弓部动脉瘤的外科治疗

目的：总结升主动脉和弓部动脉瘤手术治疗经验，以期进一步提高手术疗效。方法：自2000年7月至2002年5月应用深低温停循环（DHCA）和上腔静脉逆行脑灌注（RCP）技术手术治疗升主动脉和弓部动脉瘤20例，其中急症手术5例。施行全弓置换术2例，全弓置换和象鼻手术3例，半弓置换术15例。同期行Bentall手术8例，升主动脉置换术或同时行主动脉瓣置换术12例，冠状动脉旁路移植术1例。结果：术后早期死亡1例，短时间浅昏迷1例，呼吸功能不全2例，肾功能不全2例，无晚期死亡。结论：DHCA和RCP技术是手术治疗升主动脉和弓部瘤的安全、有效方法，急性A型夹层动脉瘤的手术方式取决于内膜破裂口的位置；正确掌握DHCA和RCP技术，手术方式和手术技术、围术期处理是提高手术疗效的关键因素。     

Operation of mid-arch coarctation.

BACKGROUND: Coarctation occurring within the aortic arch is rare and may present difficulties during surgical repair. We describe the operative technique and outcome in 6 patients with this unusual anomaly. METHODS: Five patients had antegrade perfusion with circulatory arrest. Three patients with presubclavian narrowing (one presenting with type B dissection) were operated through extended left thoracotomy. Two precarotid and paracarotid lesions were approached through a median sternotomy. All patients were perfused antegradely from the ascending aorta and operated with hypothermic circulatory arrest. One patient who had a complex presubclavian coarctation after two previous repairs received an ascending aorta to abdominal aorta bypass graft without cardiopulmonary bypass. RESULTS: All patients survived operation and are well at a mean follow-up of 3.3 years after the procedure. None had cerebral problems or spinal cord injury. Renal function was unchanged. The mean (+/- standard error of the mean) resting gradient across the coarctation decreased from 42+/-4.0 mm Hg to 6+/-1.2 mm Hg (p = 0.0004). CONCLUSIONS: Hypothermic circulatory arrest using antegrade ascending aortic perfusion allows safe and effective repair of mid-arch coarctation. Complicated reoperations can be managed safely using ascending-to-abdominal aortic bypass.