Average Cardiopulmonary Bypass Time Research Articles

Neurocognitive functions after aortic arch repair with right brachial artery perfusion

Background Satisfactory neurologic outcome following aortic arch repair through right brachial artery perfusion is well established. However, how neurocognitive functions are affected following selective cerebral perfusion, still needs to be elucidated. Methods In a period between April 2002 and March 2003, 22 patients (19 male, 3 female, with a mean age of 46.8 ± 12; range: 26 to 70 years old), underwent aortic arch repair using right brachial artery low flow (8 to 10 mL · kg −1 · min −1) selective antegrade cerebral perfusion under moderate hypothermia (26°C). There were 6 Stanford type-A dissections and 16 ascending aortic aneurysms. All patients were evaluated preoperatively and postoperatively (at seventh day and second month) for neurocognitive functions. Results There was no operative mortality. The average cardiopulmonary bypass time was 115.0 ± 24.2 minutes and the average antegrade cerebral perfusion time was 29.8 ± 7.1 minutes (19 to 38 minutes). No major neurologic deficit was observed in the postoperative period. In terms of neurocognitive test results, between the preoperative and postoperative assessments for both hemispheric cognitive functions no deterioration was detected. Conclusions The low-flow selective antegrade cerebral perfusion technique through the right brachial artery may safely be used for the great majority of patients undergoing aortic arch repair without causing deteriorations in neurocognitive functions.

Supraclavicular control of patent internal thoracic artery graft flow during aortic valve replacement

Background The mortality and morbidity of aortic valve replacement (AVR) after prior coronary artery bypass surgery (CABG) with patent left internal thoracic artery (LITA) is significant. The risk of LITA injury and inadequate myocardial preservation during the cross-clamp period may cause myocardial pump failure. Methods A total of 43 patients with a patent LITA graft underwent AVR. The patients were divided into the two groups. Group 1 included 19 patients who underwent AVR with deep hypothermia (20°C) without LITA clamping. Group 2 included 24 patients in whom LITA flow was controlled through supraclavicular occlusion and AVR performed with moderate hypothermia (28°C). Results Average cardiopulmonary bypass time (CPB) time was 118.79 ± 20.36 minutes in group 1 and 102.67 ± 9.66 minutes in group 2 ( p = 0.006). Average cross-clamp time was 53.79 ± 7.26 minutes in group 1 and 49.63 ± 6.7 minutes in group 2 ( p = 0.022). Inotropic support was required in 12 patients in group 1 and 4 patients in group 2 ( p = 0.002). Average intensive care unit stay was 4.68 ± 2.24 days in group 1 and 2.29 ± 0.46 days in group 2 ( p < 0.001). Average hospital stay was 11.84 ± 2.91 days in group 1 and 8.04 ± 2.38 days in group 2 ( p < 0.001). Mortality due to myocardial failure developed in 4 patients in group 1 but in none of the patients in group 2 ( p = 0.02). Conclusions Proximal control of LITA flow by extrathoracic supraclavicular occlusion reduces the incidence of myocardial failure due to nonhomogenous cardioplegia delivery to the anterior wall of the heart, resulting in improved myocardial protection and the elimination of the need for deep hypothermia.

Repair of atrial septal defect through a right posterolateral thoracotomy: a cosmetic approach for female patients

Background. Because the operation for atrial septal defect is considered a low-risk procedure, the cosmetic result has become an important issue. Principally for cosmetic reasons, anterolateral thoracotomy is frequently used for closure of atrial septal defect in young female patients. However, in anterolateral thoracotomy, the skin incision frequently crosses the future breast line, which may cause breast and pectoral muscle maldevelopment. Methods. We review the long-term results of a consecutive series of 126 patients in whom the atrial septal defect was closed through a right posterolateral thoracotomy. The mean age at operation was 7.1 years (range, 1 to 15 years), and the mean body weight was 23.9 kg (range, 6.9 to 56 kg). Defects repaired included 121 ostium secundum (central type), 3 sinus venosus, and 2 ostium secundum without inferior margin. Results. The average cardiopulmonary bypass time was 65 minutes (range, 37 to 130 minutes), with an average fibrillation time of 41 minutes (range, 23 to 70 minutes). There was no operative or late mortality. A majority of patients were pleased with their cosmetic results. There were no other late complications. Conclusions. Atrial septal defect can be safely repaired through a right posterolateral thoracotomy approach. This approach offers the benefit of a total absence of scarring and cosmetic disfigurement of the anterior chest wall.

Long-Term Evaluation of Orthotopically Implanted Stentless Bioprosthetic Aortic Valves in Juvenile Sheep

The aim of this study was to develop a technically feasible and reproducible model for chronic evaluation of stentless bioprosthetic aortic valves implanted orthotopically using juvenile domestic sheep. This report summarizes the results of a study conducted to assess orthotopically placed 19-mm stentless aortic bioprosthetic valves. Twenty-seven juvenile sheep underwent aortic valve replacement. Standard cardiopulmonary bypass techniques were followed. The average cardiopulmonary bypass time was 73 min. No chronic anticoagulation was used. There were two deaths (7%) due to surgical complications. In the remaining 25 experiments, 11 animals (41%) died prior to the scheduled sacrifice on postoperative day 150. One early death occurred due to coccidiomycosis infection, one due to technical error, one due to pulmonary embolus, four due to prosthetic annular size disproportion, and four due to thrombi. The remaining 14 animals (52%) underwent left and right heart catheterization, angiography, echocardiography, and sacrifice after postoperative day 150. The average weight of the sheep at elective sacrifice was 60 kg (mean weight gain 12.5 kg). The average cardiac output for the sacrificed animals was 5.1 L/min. The mean velocity of blood across the aortic valve for the sacrificed animals was 317 cm/s and the mean pressure gradient was 26.2 mm Hg. Two features suggest that this model may have broad application. First, we have demonstrated that it is technically feasible to evaluate orthotopically placed stentless bioprosthetic aortic valves in growing sheep. Second, the aortic root size of the juvenile sheep allows for implantation and evaluation of a human size aortic valve (19 mm). We believe that this model is reproducible and can be used to study stentless valve designs.

Peri-operative complications following surgical closure of atrial septal defect type II in 232 patients—a baseline study

This study intends to provide a detailed overview of the types and rates of peri-operative complications after surgical correction of an isolated ASD II. The transvenous approach to the occlusion of atrial septal defects has yielded promising results during its first 5 years of clinical trials, but before it can be established as a routine measure, definite proof is needed to demonstrate that its rate of serious complications does at least not exceed that of the surgical closure. Between 1985 and 1992, 232 consecutive patients underwent surgical closure of a secundum atrial septal defect. Among the patients 118 were children (< 18 years; 79 girls and 39 boys) with a mean age of 8.9 +/- 5.2 years (4 months-17 years) and 114 adults (74 women and 40 men) with a mean age of 28.5 +/- 10.8 years (18-69 years). Pre-operatively eight children (6.8%) and eight adults (7%) were treated for right heart failure. Mean pulmonary artery pressure was 20.4 +/- 10.4 mmHg for the children and 19.3 +/- 7 mmHg for the adults. The average pulmonary artery to systemic flow ratios were 2.9:1 and 3:1 for children and adults, respectively. Thirty children (25.4%) and 15 adults (13.2%) underwent patch closure while direct suture was the method used for the remaining patients. Average cardiopulmonary bypass time was 35.7 +/- 17.9 min for the children and 41.5 +/- 19.9 min for the adults. The length of the procedure (skin to skin) was a mean of 116 min in the young group, and 141 min in the adult group.(ABSTRACT TRUNCATED AT 250 WORDS)

Giant Cerebral Aneurysm Repair: Incorporating Cardiopulmonary Bypass and Neurosurgery

Since our initial experience on April 28, 1989, a total of nine patients have received treatment for giant cerebral aneurysm using cardiopulmonary bypass with deep hypothermia and circulatory arrest. The following data summarize our findings associated with these patients. The average patient's age was 46 years (range: 16 to 59 years of age). Seven patients were female, two were male. The procedure required approximately eight hours to complete with an average cardiopulmonary bypass time of 104 minutes (range: 60 to 140 minutes). Circulatory arrest time averaged 26 minutes (range, 12 to 45 minutes) with an average of 30 minutes (range: 10 to 62 minutes) required to cool the patient to below 18 degrees C (64 degrees F). An average of 54 minutes (range: 28 to 81 minutes) was required to warm the patient to a bladder temperature of 36 degrees C (96.8 degrees F). During the cooling period, five patients went into asystole spontaneously, four patients required bolus of 20 mEq of potassium chloride, and upon rewarming, spontaneous defibrillation occurred in six patients. Three patients were defibrillated without difficulty with external shock. The average number of blood products administered in each of the nine patients was 3.6 units of packed red blood cells, 3 units of fresh frozen plasma, and 6.5 units of platelets. Six patients recovered postoperatively without complication, and the recovery of three patients was affected by the complex anatomical location of the giant aneurysm. Cardiopulmonary bypass with deep hypothermia and circulatory arrest offers an alternative approach to the treatment of giant cerebral aneurysms considered inoperable by conventional techniques. The effectiveness of each procedure depends on the collaborative efforts of every member of the perioperative nursing team, the neurosurgical team, the cardiac surgical team, the neuroanesthesiology team, and the perfusionists. Careful planning and anticipation at every stage of the surgery can reduce surgical time, cardiopulmonary bypass time, and most importantly, circulatory arrest time.

Clinical Use of a New Membrane Oxygenator

A new oxygenator, developed by Shiley Laboratories, uses microporous polypropylene membrane material in a parallel plate design. The device has an integral heat exchanger and built-in temperature ports. The M-2000 oxygenator was used for routine cardiopulmonary bypass ( CPB) during open heart surgery on sixteen consenting adult patients. Mean age of the group was 56 years and the mean body surface area was 1.77m2. One patient had an atrial septal defect repaired, nine had coronary bypass, five had valve replacement and one, a valve replacement with coronary bypass. The average CPB time was 105 minutes. The circuit was primed with 2000 ml of balanced electrolyte solution and 500 ml of 6% hydroxyethyl starch in 0.9% saline to which 1500 units of heparin had been added. Average normothermic blood gas values were; PaO2=242 mm Hg, PaCO2=32.5 mmHg. During hypothermia the temperature corrected mean values were; PaO2=155 mm Hg and PaCO2=31 mm Hg. Hematological changes observed were hematocrit and hemoglobin concentrations decreased 33% due to dilution. Platelet counts decreased 46%. Plasma hemoglobin values increase a by 19.6 mg/dl. The M-2000 presented no problems to the investigators during this study. It exchanged gases in a satisfactory manner and is gentle in its blood handling properties.

Coexistent carotid and coronary artery disease. Surgical management.

We performed simultaneous coronary artery bypass grafting (CABG) and carotid endarterectomy (CE) in 42 patients (average age, 61 years). Twenty-nine patients had preoperative transient ischemic attacks. Carotid arteriography showed stenosis (greater than 70%) in 38 subjects and extensive ulcerated lesions in two, and two emergency patients were not studied. Carotid artery dissection and sternotomy were simultaneously performed and the patients were cannulated for cardiopulmonary bypass (CPB). We undertook CE (22 left and 24 right) using EEG monitoring prior to CPB in all but one patient. The average carotid occlusion time was 25 minutes without a shunt in 23 patients and 5.5 minutes with a shunt in 19 patients. After CE, CABG was performed with an average aortic clamp time of 39 minutes and an average CPB time of 87 minutes. The operative mortality was 5% (2/42). There were no strokes or perioperative myocardial infarctions. Neurologic morbidity consisted of postoperative headache in one patient, transient upper-extremity weakness in two patients, and transient facial weakness in one patient. The average length of postoperative hospitalization was ten days. Currently, patients with symptomatic coronary artery disease and concomitant carotid bruits with positive noninvasive testing and arteriography should have simultaneous repair of these lesions.