Search

The use of cardiopulmonary bypass is still necessary for the repair of many congenital cardiac defects. However, exposure to cardiopulmonary bypass can still lead to major morbidity and sometimes mortality, especially in neonates and infants, despite a perfect surgical repair. Various research-based strategies have been used to minimize some of the complications related to cardiopulmonary bypass, including the systemic inflammatory response, hemodilution, and transfusion requirement. This overview provides some of the strategies that we use in our practice in applying cardiopulmonary bypass in the repair of congenital cardiac defects in neonates and infants.

Sergei S. Brukhonenko designed and constructed one of the earliest heart-lung machines. He was the first to experimentally perform a total body perfusion with the heart of the animal isolated from the circulation. His work paved the way to the first experimental operations on heart valves. Although Brukhoneko's pioneering contributions have not received the recognition they deserve, his work represents an important landmark in cardiac surgery.

Background . Excision of large right atrial masses requires bicaval cannulation and cardiopulmonary bypass. Safe venous cannulation can be accomplished only by knowing the exact intracavitary location and extension of the mass to avoid fragmentation. Transthoracic echocardiography and intraoperative transesophageal echocardiography, although helpful, cannot always define the exact intracavitary relationships of the tumor. Methods . We have used both intraoperative transesophageal and epicardial echocardiography to guide venous cannulation in 4 patients with large right atrial masses. Both echo images are used by the surgeon to select the exact site and method of cannulation to avoid fragmentation of the mass. Epicardial echocardiography complemented the images obtained by transesophageal echocardiography. Results . The technique of combined transesophageal and epicardial echocardiography allowed safe venous cannulation in all 4 patients. Each of the right atrial masses was safely excised using case-specific cannulation techniques guided by the echocardiographic images. Conclusions . We propose the routine use of both intraoperative transesophageal and epicardial echocardiography in guiding venous cannulation for safe excision of large right atrial masses.

Experience in the surgical management of congenital heart defects led to the advent of open heart surgery as it is known today. Only after 1938, when Robert Gross first ligated a patent ductus arteriosus, did congenital anomalies yield to correction. Success with these anomalies encouraged surgeons to attempt other extracardiac and intracardiac repairs. These attempts resulted in a steady flow of advances that culminated in the practical application of cardiopulmonary bypass and the procedures it made possible. Today, less than 60 years since Gross's landmark operation, surgical intervention can fully or partially correct 95% of congenital heart defects.

The concept of cardiopulmonary bypass is more than a century old. Although the first clinical application occurred in 1953, there were great deficits in knowledge and materials that had to be overcome before we could achieve the outcomes of cardiac surgery that we have today.

Recent studies suggest that patients undergoing warm heart surgical procedures have reduced postoperative bleeding. To determine if this is due to differences in platelet activation, we measured platelet membrane glycoproteins (GPIb, GPIIb/IIIa, GMP 140), platelet fragments, and platelet counts before, during, and after normothermic (37 degrees C) or hypothermic (28 degrees to 30 degrees C) cardiopulmonary bypass. Cardiopulmonary bypass was associated with a significant decrease in platelet count, platelet membrane GPIb, and platelet fragments, and an increase in GMP 140 (p0.05). Normothermic cardiopulmonary bypass induced an early significant increase in granulocytes, whereas this was delayed until after rewarming in the hypothermic group. Mean 24-hour postoperative blood loss was 786 +/- 226 mL in the cold group versus 547 +/- 56 mL in the warm group (p = not significant). We conclude that cardiopulmonary bypass affects platelet activation and integrity and that these changes are similar in direction and magnitude for hypothermic and normothermic techniques.

The present case of cardiopulmonary bypass malperfusion demonstrates the usefulness of transesophageal Doppler echocardiographic monitoring during repair of acute aortic dissection.

Retrograde coronary sinus cardioplegia is being used for myocardial protection with ever-increasing frequency during complex cardiac operations. New methods for introducing cardioplegia into the coronary sinus have been facilitated by improved balloon-tipped catheters. Moreover, various solutions are being infused under both hypothermic and normothermic conditions with good results. This report provides background into the application of this technique and illustrates several methods for its daily use in clinical cardiac surgery.

This systematic review and meta-analysis explores the clinical efficacy of biocompatible surfaces for cardiopulmonary bypass in adults. Thirty-six randomized controlled trials were retrieved for a total of 4360 patients. Patients treated with biocompatible circuits had a lower rate of packed red cells transfusions and atrial fibrillation, and shorter durations of stay in the intensive care unit. When the analysis was limited to high-quality studies, only a reduction in atrial fibrillation rate and a shorter stay in the intensive care unit remained significantly associated with the use of biocompatible surfaces. Using biocompatible surfaces without other measures to contain blood activation results in a limited clinical benefit.

Conventional neonatal cardiopulmonary bypass requires the use of large volumes of allogeneic blood to prevent unacceptable hemodilution. Evidence is accumulating to suggest that the use of blood products during cardiopulmonary bypass has a negative effect on clinical recovery through inflammatory side effects. This would suggest an advantage for eliminating blood use in infant cardiopulmonary bypass through circuit miniaturization. In this article, we review the data supporting this rationale and provide the results from studies in our laboratory that emphasize the benefits of circuit miniaturization.

Background Cardiopulmonary bypass (CPB) has been reported to increase oxygen metabolism and to influence the relation between oxygen consumption (Vo 2 ) and delivery (DO 2 ) in the early hours after cardiac surgery. To investigate the role of CPB, we studied oxygen metabolism in coronary artery bypass procedures performed on-pump (CABG) and off-pump (OPCAB). Methods Twenty-five patients were randomized to undergo CABG (n = 14) or OPCAB (n = 11). All patients received the same anesthetic management. Oxygen metabolism variables were assessed before induction of anesthesia and up to 18-hours after surgery. Results At baseline, before induction of anesthesia, there were no differences between CABG and OPCAB in oxygen consumption (VO 2 ), delivery (DO 2 ), or extraction (ExO 2 ). After surgery VO 2 and ExO 2 increased in both groups, while DO 2 decreased. No significant differences between CABG and OPCAB were detected in postoperative VO 2 , DO 2 , and ExO 2 levels. The relation between VO 2 and DO 2 was very similar in CABG and OPCAB patients throughout the study, and no significant differences were detected in slopes and intercepts of the regression lines between CABG and OPCAB at all time points. There was, however, a significant effect of time on the relation between VO 2 and DO 2 : this relation was stronger in the postoperative period, and the slope of this relation increased over time as well. Conclusions A hypermetabolic state and progressive and significant increases in the strength of the relationship between VO 2 and DO 2 and in the slope of this relationship occur after both CABG and OPCAB. Cardiopulmonary bypass is not responsible for these changes in oxygen metabolism.

Complement and fibrinolytic factors were measured in 9 infants undergoing hemofitration immediately after cardiopulmonary bypass in an attempt to reduce activation of these systems. Plasma levels of C3a, C5a, and terminal complement complexes increased during bypass by 460%, 85%, and 745%. Plasma levels were reduced after hemofiltration in 8 of the 9 infants, and C3a and C5a fractions were recovered in the ultrafiltrate. The observed activation of the fibrinolytic system seemed to be unaltered by hemofiltration. Fibrinolytic factors were not filtered. Our study shows that increased concentrations of complement factors in the plasma after bypass in infants may be reduced by hemofiltration.

was safe, effective, and suitable especially in patients with high risks for coronary artery bypass grafting.

Seven anticoagulants besides unfractionated heparin have been used for human cardiopulmonary bypass (CPB), mainly in patients with heparin-induced thrombocytopenia. The collective experience with these alternative anticoagulants provides a perspective on current efforts aimed at improving CPB anticoagulation. Unfortunately, each alternative currently lacks a standard dosing schedule and a reliable method of monitoring the adequacy of its anticoagulant effect during CPB. Most also lack proven antidotes. Thus, unfractionated heparin remains the anticoagulant of choice for standard CPB.

Cardiopulmonary bypass (CPB) induces an increased capillary permeability and tissues water content due to hemodilution and the inflammatory response, resulting in organ dysfunction. The reduction of the water accumulation and inflammatory response can be achieved by employing ultrafiltration during CPB. Recently we developed a simple CPB circuit for ultrafiltration using the aortic venting tube as an inlet line. Such a technique offers the advantages of performing a combined ultrafiltration procedure and eliminating the danger of air embolism. We employed this circuit in 12 consecutive pediatric patients undergoing open heart surgery.

To combine the advantages of conventional and modified ultrafiltration while keeping cardiopulmonary bypass technique simple, we have developed a simplified circuit of combined ultrafiltration, which is presently used in our pediatric patients. In addition to the benefits of combined ultrafiltration, this circuit allows the rewarming and prevention of heat loss in small children and neonates.

Although modified ultrafiltration after pediatric open heart operations is used by several clinical centers, the risk of complications is a matter of concern. This report describes a simple, reliable, and reproducible technique of speed-controlled venovenous modified ultrafiltration.

Despite its initial description more than 20 years ago, combined orthotopic heart and liver transplantation is still performed infrequently. We report a 53-year-old man with familial hypertrophic restrictive cardiomyopathy who presented with right heart failure and end-stage liver failure and required combined orthotopic heart and liver transplantation. Rather then using a staged approach, the surgery was performed using a technique of simultaneous implantation supported by cardiopulmonary bypass. The relative merits of using a simultaneous approach are discussed. The patient had an uneventful postoperative course and went home on postoperative day 14.

We describe transapical aortic cannulation in pediatric patients. This technique may help to establish cardiopulmonary bypass in small children in whom aortic root cannulation is undesirable or not feasible.

Continued experience with the TCI Heartmate Ventricular Assist System has led to improvements in our ability to avoid and manage right heart dysfunction during weaning from cardiopulmonary bypass. The advent of the electric device has intensified the need for these techniques because of its elevated minimal heart rate (50 beats/min) at start-up and the demands this places on the native right heart. We have developed and here describe a technique we have used successfully in our last 8 patients to assist in deairing and filling of the ventricular assist device, to partially support the right heart during the initial wean from cardiopulmonary bypass, and to avoid occasional overdistention of the right heart during early high left ventricular assist device flow.

Background . The presence of impaired phagocytic function of the reticuloendothelial system after cardiac operations using cardiopulmonary bypass remains controversial. Methods . In this study, the phagocytic function of granulocytes in 14 patients undergoing cardiac operations with cardiopulmonary bypass was examined using a chemiluminescence method. Seven patients with abdominal aortic aneurysms served as controls. Electron microscopy also was employed to evaluate morphologic changes. Results . The 14 cardiac patients showed impaired phagocytic function from immediately after operation until 12 hours after the operation. This phagocytic function recovered within 24 hours. The 7 control patients showed no change in phagocytic function during or after the operation. Scanning electron microscopic examination of the cardiac patients' granulocytes revealed the loss of villi on cell surfaces immediately after operation. However, these villi were restored within 24 hours after the operation. Conclusions . The phagocytic function of granulocytes was impaired in the early postoperative period in patients undergoing cardiopulmonary bypass, and this was probably due to the loss of villi on granulocyte surfaces.

Air embolism remains a potential hazard of cardiopulmonary bypass. We describe a simple technique for deairing the heart that is inexpensive and requires no manipulation or extra cannulation of the heart.

We describe a very simple method to minimize the systemic hemodilution associated with crystalloid cardioplegic solutions, either in an antegrade or retrograde fashion.

Attempts at cardioscopy have been hampered by the inability to see through blood. We describe a new method of intracardiac fiberscopic visualization performed in sheep using cardiopulmonary bypass, asanguineous cardjoplegic arrest, and replacement of intracardiac blood with a clear fluid. Right heart endoscopic visualization was achieved in 4 sheep using a method that could allow extrapolation to a percutaneous approach. Two of these animals were weaned successfully from cardiopulmonary bypass. Venting and flushing aspects of the procedure were of primary importance. Further development of this technique may open the way to percutaneous endoscopically guided intiacardiac operations in humans.

We have used transventricular aortic cannulation as arterial inflow from the heart-lung machine in seven consecutive operations done in 1 year for acute aortic dissection. Satisfactory cardiopulmonary bypass was achieved in all patients.

The purpose of this article is twofold: to describe our technique for performing coronary artery bypass grafting without cardiopulmonary bypass (off pump) and to demonstrate that this operation is safe, in terms of mortality and certain indices of morbidity. Very little has been published in regard to off-bypass operations. From 1985 through 1990, 220 patients underwent operation off bypass; 220 on-pump controls were retrospectively matched for number of grafts, left ventricular function, and date of operation. Groups were compared in terms of mortality and ten indicators of morbidity. The same analysis was performed for ten subgroups. We found no statistically significant difference between groups in mortality (off pump, 1.4% [3/220]; on pump, 2.4% [5/220]), which held across all subgroups. Patients undergoing operation off pump required blood far less often (not transfused: off pump, 72.7% [160/220]; on pump, 54.6% [116/220]; p = 0.005 by Fisher's exact test), and the low output state occurred statistically less frequently off pump (off pump, 5.5% [12/220]; on-pump, 12.7% [28/220]; p = 0.01 by Fisher's exact test). Further research should be directed to which subgroups can be operated on to advantage off pump and which, if any, groups of patients should be confined to on-bypass operations.

A case of successful emergency reoperation for mitral valve replacement 2 hours after a cesarean section is reported. The use of aprotinin (Trasylol; Bayer AG, Leverkusen, Germany) greatly simplified the surgical procedure and was in our opinion the most important factor in an uncomplicated outcome.

A technique for rapid transfusion after aortic decannulation is presented. This technique facilitates the repair of the aortic cannulation site in difficult circumstances.

A 46-year-old man could not be weaned from ventilatory support while receiving procainamide. When the drug was discontinued, the patient was successfully weaned shortly thereafter.

The dual-stage venous cannula is widely used but can obstruct the surgeon's view and interfere with operative procedures in the aortic root. We designed a new stainless steel sheath for a dual-stage venous cannula that enables the cannula to bend and maintain the appropriate angle for the surgical procedures. We suggest that operative procedures in the aortic root can be performed faster during safety cardiopulmonary bypass by use of a dual-stage venous cannula bent by application of this new sheath.

Inadequate venous drainage may represent a major problem in operations on the descending thoracic aorta performed with the aid of cardiopulmonary bypass. We herein describe an alternative technique of venous cannulation, which allows steady performances and high pump flows.

We present 2 cases of failed coronary angioplasty, with hemodynamic compromise, where emergency coronary artery bypass grafting was performed without cardiopulmonary bypass. The hypodynamic nature of the stunned myocardium in this circumstance allows this technique to be applied with relative ease to accessible vessels. As a consequence, reduced morbidity and hospital stay can be anticipated.

Anticoagulation for cardiopulmonary bypass in the infrequent clinical setting of thrombocytopenia associated with the use of unfractionated heparin is a very serious problem. We describe a case in which a low-molecular-weight heparin (tedelparin) was selected for this purpose based on a platelet aggregation test, permitting adequate anticoagulation during cardiopulmonary bypass for valve replacement. This case report might help establish an adequate anticoagulation protocol when faced with a patient suffering from this condition.

We present a technique of femoral cardiopulmonary bypass that allows excellent venous drainage. This is accomplished by augmenting the venous return with a centrifugal pump.

A simplified method of transatrial cannulation of the coronary sinus during cardiopulmonary bypass, with the heart completely decompressed, is described. The technique is easy to adopt and inherently safe because the catheter is guided toward the great cardiac vein visually, rather than by manual palpation.

In certain diagnostic entities temporary occlusion of the pulmonary veins during cardiopulmonary bypass essentially eliminates the left ventricular return of blood. This, in turn, improves visualization of the operative field and enhances myocardial hypothermia by preventing rewarming of the left ventricle to the perfusate temperature. Two methods of easily accomplishing pulmonary vein clamping are described.

Cardiac surgeons have become more cognizant of the syndrome of noncardiogenic pulmonary edema after cardiopulmonary bypass. Although this syndrome is rare, its occurrence can be catastrophic. This article reviews the current understanding of several factors that have been implicated in the cause of this syndrome and discusses the various options for management of the problem once it has arisen.

Intracellular sodium and calcium were measured in 30 isolated perfused rat hearts exposed to normothermic ischemic intervals varying from 0 to 40 minutes followed by 35 minutes of reperfusion. Accumulation of these elements was correlated with alterations in postischemic isovolumic contractile function. There were increases in calcium of 207%, 390%, and 681% of the nonischemic control following reperfusion after respective ischemic intervals of 30, 35, and 40 minutes. These corresponded to decrements in peak developed pressure of 23.8% after 30 minutes, 68.6% after 35 minutes, and no recovery of function after 40 minutes of ischemia. Thirty-five and 40 minutes of ischemia produced 138% and 170% increases in intracellular sodium, respectively. These data show that there is a graded accumulation of intracellular sodium and calcium that correlates with the duration of ischemia and the degree of functional impairment in the postischemic heart. Measurement of intracellular sodium and calcium may, therefore, serve as an adjunct to other biochemical and functional factors used to quantitate postischemic and postcardioplegic damage in the development of new myoprotective regimens.

The ability to predict cardiac output (CO) before termination of cardiopulmonary bypass (CPB) allows identification of potential complications once the patient is off bypass. We have previously demonstrated that CO early after CPB can be reliably predicted by a plot of venous oxygen saturation at various flow rates on CPB, based on in-line monitoring of venous oxygen saturation. In this study, we evaluated a simplified technique for predicting CO with a series of 50 patients on CPB. When CPB weaning began, patients were normothermic, anesthetized, and paralyzed. Venous oxygen saturation and arterial blood flow were recorded. At low pump flow just before termination of CPB, the final venous oxygen saturation was recorded. Assuming a proportional relationship between venous oxygen saturation and arterial blood flow, CO early after CPB was predicted. The simplified CO prediction was compared with the thermodilution CO immediately after CPB. The simplified technique reliably predicted CO early after CPB compared with the thermodilution technique. The simplicity and reliability increase the clinical value of the CO prediction.

A technique for autotransfusion of shed mediastinal blood using the cardiotomy reservoir is described that offers several advantages over currently available autotransfusion systems.

A simple technique in which the retrosternal tissues are dissected from the body of the sternum under direct vision, allowing for relatively quick and safe reentry of the sternum, is presented.

The Omni sucker was designed and made from foam silicone sheet to obtain maximum collection of blood and crystalloid solution in the pericardium and to return blood and crystalloid solution into the cardiopulmonary bypass circuit during open-heart surgery. Wall suction use was minimized so that the least amount of blood was discarded during cardiopulmonary bypass.

The value of oxygenated, aqueous, cold cardioplegic solutions is being evaluated at several centers. The theoretical advantages of such a solution are counter-balanced in part by the complexity and expense of the preparation and delivery systems that have been used. A simple method is described that effectively achieves satisfactory levels of oxygenation of the cardioplegic solution within its original vinyl container.