Surgery for descending thoracic aortic anastomotic aneurysms with a temporary external bypass method

(Received for publication on Oct. 7, 1997; accepted on July 7, 1998)     

Blood conservation in thoracic aortic surgery with total cardiopulmonary bypass

BACKGROUND: In thoracic aortic surgery, a large number of homologous transfusions sometimes cause systemic inflammatory response, which may lead to pulmonary dysfunction, renal dysfunction and brain edema. To predict the need for homologous blood transfusion in aortic surgery, we use blood transfusion index (preoperative Ht x body weight) to predict the magnitude of homologous transfusion. PATIENTS AND METHODS: From Dec 1997 to May 2000, 59 consecutive patients were underwent thoracic aortic graft replacement with total cardiopulmonary bypass. These patients were divided in 2 groups, who were underwent graft replacement without blood transfusions, and who needed blood transfusions. Each group was compared in age, sex, emergency, Ht, CPB time, blood transfusion index and operative mortality. RESULTS: Forty patients (67.7%) did not required blood transfusion. In elective cases (32 cases), 84.3% were underwent operation without blood transfusion. There was no significant difference between 2 groups in terms of age and mean bypass duration. Blood transfusion index was significantly higher in transfusion group (2,320 +/- 784) compared with that in not transfusion group (1,445 +/- 706). CONCLUSION: Blood transfusion index was useful preoperative parameter to predict the need for homologous transfusion.     

Surgical treatment of descending thoracic aortic aneurysm under temporary bypass with antithrombogenic tube and bio-medicus centrifugal pump

Four patients with descending thoracic aortic aneurysm were successfully operated on under temporary bypass with an antithrombogenic tube and a Bio-Medicus centrifugal pump. The bypass flow ranged from 1.0 to 2.4 l/min with the mean femoral artery pressure of 50 to 70 mmHg. No complications such as paraplegia, hepatic dysfunction or renal failure were encountered in all the patients. Temporary increment of the serum amylase level occurred in all the patients, but any apparent clinical symptoms were not present. The temporary bypass method with an antithrombogenic tube and a centrifugal pump is useful and reliable for surgical treatment of descending thoracic aortic aneurysm.     

Analysis of thoracic aortic blood flow during off-pump coronary artery bypass surgery.

OBJECTIVES: The non-invasive monitoring of thoracic aortic blood flow (TABF) during off-pump coronary artery bypass (OPCAB) surgery is becoming more commonly used and proved to be invaluable in the early detection of haemodynamic compromise due to heart displacement. The aim of this study was to analyze the changes in the TABF during OPCAB using transoesophageal Doppler and compare them with the changes observed by other monitoring methods as cardiac output, invasive pulmonary and radial pressures and mixed venous oxygen saturation. METHODS: The measurements obtained from classic haemodynamic monitoring methods including the radial artery line and the pulmonary artery catheter with continuous monitoring of the cardiac output and mixed venous blood oxygen saturation were compared to the measurements of TABF obtained from a transoesophageal Doppler probe in 15 consecutive patients who underwent OPCAB surgery. RESULTS: The TABF decreased significantly during the construction of coronary anastomoses from 3.42 +/- 0.94 l/min (baseline) to 2.2 +/- 0.8 l/min during the first coronary anastomosis and then to 2.14 +/- 1.12 l/min during the second coronary anastomosis (F=4.29, P=0.008). TABF returned to the baseline values (2.85 +/- 1.19 l/min) at chest closure. The cardiac output measurement showed no significant decrease compared to baseline. CONCLUSIONS: Low TABF occurred without significant changes in the measurements obtained from classic haemodynamic monitoring methods during OPCAB surgery. This finding could be of vital importance in helping improve the monitoring and consequently the management of patients undergoing OPCAB surgery.     

Surgical treatment of ischemic heart disease using internal thoracic artery and partial ileal bypass]

The authors recommend complex two-stage treatment of ischemic heart disease, including a reconstructive operation on the coronary arteries and an operation for correcting the disturbed plasma lipid spectrum (partial ileal bypass). The results of operative treatment of 150 patients with the use of the internal thoracic artery were studied. The authors emphasize the advantages of this operation over one using an autovein graft. Complex operative treatment was conducted in the clinic in 60 patients with a good clinical effect. The authors also recommend operation for partial ileal bypass as an independent intervention in dyslipoproteinemia and diffuse affection of the coronary arteries.     

Descending thoracic aortic aneurysm repair with the aid of partial cardiopulmonary bypass: heparin-coated circuits versus nonheparin-coated circuits

BACKGROUND: We have performed descending thoracic aortic aneurysm repairs with partial cardiopulmonary bypass, including heparin-coated circuits. The aim of this study was to evaluate (i) the impact of partial cardiopulmonary bypass on distal organ function and surgical outcomes; and (ii) the effectiveness of using heparin-coated circuits for preventing bleeding complications. METHODS: From July 1980 to June 2004, 309 patients underwent descending thoracic aortic aneurysm repairs using partial cardiopulmonary bypass. Their mean age was 61 years (range 19-81 years). One hundred of the 309 patients underwent repair of descending thoracic aortic aneurysm with heparin-coated circuits. Blood data for renal and hepatic function were collected on the day before the operation and postoperative days. RESULTS: The in-hospital mortality was 15%. Distal organ dysfunction included spinal cord dysfunction in 2 patients (0.7%) and renal failure necessitating hemodialysis in 15 patients (5%, 15/297: excluded 12 dialysis patients). Multivariate analyses showed that preoperative hemodialysis and emergency operation were risk factors for operative mortality and that emergency operation was a risk factor for requiring hemodialysis. Renal and hepatic function normalized by 2 weeks after surgery. There were no significant differences between the heparin-coated group and nonheparin-coated group in amounts of packed red cells, fresh frozen plasma, and platelets transfused during the procedures. CONCLUSIONS: Our data showed that partial cardiopulmonary bypass is a safe and effective method for distal perfusion. Using this technique, descending thoracic aortic aneurysm repair can be performed with acceptable mortality and morbidity. However, the superiority of heparin-coated circuits over nonheparin-coated ones was not proved.     

A case report of aortic wall reconstruction utilizing heparin-coated temporary bypass tube and roller pump system]

A 51-year-old man with stage IIIB (T4N2M0) adenocarcinoma of the lung underwent left pneumonectomy and aortic wall resection. In this operation a heparin-coated tube and roller pump system were used. Advantages of a heparin-coated tube and roller pump system for temporary bypass are as follows. 1) simple operative procedure. 2) controllable bypass flow. 3) no need for anticoagulants.     

Open distal anastomosis in conjunction with partial cardiopulmonary bypass and mild hypothermia for repair of descending thoracic aortic aneurysms

The duration of spinal cord ischemia is probably the most important single factor in the pathogenesis of paraplegia after repair of descending thoracic aortic aneurysms. We describe a modification of open distal anastomosis technique originally presented by Dr. Cooley, in which we use partial cardiopulmonary bypass with femoral cannulation and mild hypothermia. Cardiopulmonary bypass is interrupted after lowering patient's temperature to 32 degrees C and the aorta is clamped using one proximal clamp. During the suturing of the distal anastomosis blood is sucked to reservoire and returned oxygenated to the patient via the venous line using a shunt which is installed between the arterial and venous lines. After completion of the distal anastomosis the graft is clamped and cardiopulmonary bypass reinstituted. Rewarming is started as bleeding intercostal arteries are sutured and proximal anastomosis performed. This modification shortens the distal ischemia time, but supports the circulation of the kidneys and splanchnic area immediately after the distal anastomosis is finished. Lowering the temperature should give additional protection for the spinal cord and the blood can be returned oxygenated to the patient. In our opinion, this combination of femoro-femoral perfusion, mild hypothermia, and open distal anastomosis offers several benefits and can be used in dissections and aneurysms, which extend up to aortic hiatus.