Anesthesiology: Problem-Oriented Patient Management

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CASE 10: Transposition of the Great Arteries

Serle K. Levin

John S. Whittington

Quick Links to Sections in this Chapter

–A. Medical Disease and Differential Diagnosis

–B. Preoperative Evaluation and Preparation

–C. Intraoperative Management

–D. Postoperative Management

A 6-day-old, full-term, 3.4-kg male infant was scheduled for an arterial switch operation (ASO). At birth, he was severely cyanotic and underwent an atrial septostomy during cardiac catheterization with improvement in his oxygenation. Prostaglandin E1 had been administered initially but was discontinued after the septostomy. His arterial oxygen saturation was 70%, blood pressure 63/37 mm Hg, pulse 145 beats/minute, and respiration 46 breaths/minute.

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  1. Medical Disease and Differential Diagnosis
    1. What is transposition of the great arteries (TGA)?

    2. What is the embryologic development leading to TGA?

    3. What is the anatomy and physiology of TGA?

    4. What is congenitally corrected TGA?

    5. What are the preoperative issues pertaining to the coronary arteries?

    6. What are the clinical variations of d-TGA?

    7. What is the differential diagnosis of TGA and how is the diagnosis made?

    8. What preoperative interventions can help stabilize the patient?

    9. What determines the oxygen saturation in patients with TGA and why?

    10. Discuss the development of pulmonary vascular occlusive disease (PVOD) in patients with d-TGA.

    11. What are the surgical options for repair? Why is one chosen over the others?



  2. Preoperative Evaluation and Preparation
    1. What information is important to prepare for this case?

    2. What will we do as anesthesiologists to make things better or worse?

    3. How would you prepare your operating room?



  3. Intraoperative Management
    1. How would you monitor this baby?

    2. What would be the best method of induction?

    3. What are the pre-coronary pulmonary bypass (pre-CPB) issues?

    4. Is CPB in pediatrics different from adults?

    5. How does the surgeon correct this lesion?

    6. What is hypothermia and how is it classified? Circulatory arrest? Low-flow CPB?

    7. What are the physiologic changes and potential complications associated with hypothermia?

    8. What parameters are measured on CPB?

    9. What are the major issues when separating from CPB?

    10. What are the immediate post-CPB issues following arterial switch operation (ASO)?



  4. Postoperative Management
    1. What are the management issues in the intensive care unit?

    2. What is JET?

    3. What are the surgical problems seen after correction of d-TGA?

    4. What are the long-term outcomes after repair of d-TGA?



A. Medical Disease and Differential Diagnosis

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A.1. What is transposition of the great arteries (TGA)?

TGA is a form of cyanotic congenital heart disease. As the name suggests, the great arteries are transposed as they relate to the heart. The aorta arises from the right ventricle (RV) and the pulmonary artery arises from the left ventricle, opposite of the normal ventriculoarterial relationship. The discordance between the ventricle and great vessels creates two parallel circulations.

A relatively uncommon disease, TGA accounts for only 5% to 7% of all congenital heart disease and has an incidence of 0.2 cases per 1,000 live births. If uncorrected, TGA has a 30% mortality rate in the first week of life, 45% in the first month, and 90% in the first year. Overall survival has improved dramatically over the last 30 years because of improvements in surgical and medical therapies.

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Casteñada AR. Jonas RA. Mayer JE, et al.Cardiac surgery of the neonate and infant Philadelphia: WB Saunders, 1994:409–438.

Kaplan JA, Reich DL, Konstadt SN, Cardiac anesthesia4th ed. Philadelphia: WB Saunders, 1999:801–813.

A.2. What is the embryologic development leading to TGA?

Normal embryologic development begins with the formation of a simple cardiac tube at 3 to 4 weeks gestation (Fig. 10.1A). As the tube grows, it differentiates into the sinoatrium (SA), primitive ventricle (V), bulbus cordis (BC), and truncus arteriosus (TA) (Fig. 10.1B). All four of these structures are connected in series. The sinoatrium ultimately evolves into the right and left atrium. The primitive ventricle becomes the left ventricle, and the bulbus cordis becomes the RV. The truncus arteriosus divides into the pulmonary artery and the aorta (Fig. 10.1A).

Figure 10.1. Embryologic transition of the straight cardiac tube to the four-chambered heart. (From Rudolph AM, ed. Rudolph's pediatrics, 20th ed. Stamford, CT: Appleton & Lange, 1996:1414, with permission.).


To have a single tube become a four-chambered structure, the cardiac tube has to bend and rotate to align all of these structures (Fig. 10.1C). This rotation occurs during the second month of embryologic development. The sinoatrium bends on itself to position the right and left atria adjacent to each other. The atrioventricular (AV) canal connects them to the ventricle and bulbus cordis. The early right and left ventricles bend and rotate so that the RV is positioned beneath the right atrium and the left ventricle is beneath the left atrium. Differential tissue growth forces the RV to move anteriorly and to the right of the left ventricle (Fig. 10.1D). This is referred to as a D-loop. In the event that the RV moves to the left, an L-loop is created and the RV ends up on the left side of the heart, below the left atrium.

The four chambers and the two circulations are finally separated when the endocardial cushions divide the AV canal (Fig. 10.1E). The endocardial cushions provide an anchoring point for the atrial septum, the posterior portion of the ventricular septum, and the tissue that becomes the tricuspid and mitral valves.

The outflow of the ventricles into the great vessels—the conotruncal segment of the cardiac tube—undergoes septation to separate the right and left ventricular outflow tracts, pulmonic and aortic valves, and the two great arteries. At the conclusion of this septation, a ridge of muscle (the subpulmonic conus or infundibulum) extends below the pulmonic valve, separating the annulus of the pulmonic and tricuspid valves and contributing to the right ventricular outflow tract. The aortic valve and the left ventricular outflow tract have no ridge of muscle, thereby, allowing the mitral and aortic valve annulus to be in continuity.

Hypoplasia of the conotruncal swellings responsible for this septation has been proposed as the cause of TGA. Hypoplastic truncal swellings and the development of additional abnormal truncal swellings were observed in a mouse model of d-TGA. The explanation behind these findings suggests that abnormal development of the conotruncal swellings leads to incorrect division of the conotruncus resulting in TGA.

An alternate theory attributes TGA to an abnormality in conal differentiation below the semilunar valves. Instead of having resorption of the subaortic conus and the development of the subpulmonic conus, the opposite occurs. This leads to the aorta arising from the RV and the pulmonary artery arising from the left ventricle. In addition, the pulmonic and mitral valve annuluses are in continuity.

Figure 10.2. Pattern of blood flow in normal (series) and in transposition (parallel) circulations. Dashed lines represent potential sites of intercirculatory mixing.


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Grifka RG. Cyanotic congenital heart disease with increased pulmonary blood flow. Pediatr Clin North Am 1999:46:405–425.

Kirby ML. Cardiac morphogenesis—recent research advances. Pediatr Res 1987:21:219–224.

Sadler TW, Langeman's medical embryology8th ed. Philadelphia: Lippincott Williams & Wilkins, 2000:208–259.

Yasui H. Nakazawa M. Morishima M, et al.Morphological observations on the pathogenetic process of transposition of the great arteries induced by retinoic acid in mice. Circulation 1995:91:2478–2486.

A.3. What are the anatomy and physiology of TGA?

In d-transposition, the aorta arises from the RV and the pulmonary artery arises from the left ventricle. The looping of the ventricles is normal (D loop), but the great vessels align incorrectly. The positioning of the great vessels in relationship to each other is variable. Blood flow is broken into two parallel but separate circulations—a systemic circuit recirculating deoxygenated blood and a pulmonary circuit recirculating oxygenated blood (Fig. 10.2).

Areas of mixing are vital to the survival of the baby. The possible locations for mixing are via a patent foramen ovale (PFO), atrial septal defect (ASD), ventricular septal defect (VSD), patent ductus arteriosus (PDA), or through bronchopulmonary collaterals. Without mixing, the two circuits remain separate, leading to death from systemic hypoxemia and acidosis. ASDs or VSDs permit mixing between the two circulations and, subsequently, early survival. Twenty-five percent to 45% of children born with d-TGA have an accompanying VSD. The larger the size of the communications between chambers or the greater the number of them, the more mixing of oxygenated and deoxygenated blood. The result is higher oxygen saturation and better hemodynamic stability.

A PDA can improve oxygen saturation by increasing pulmonary blood flow (PBF).

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Casteñada AR. Jonas RA. Mayer JE, et al.Cardiac surgery of the neonate and infant Philadelphia: WB Saunders, 1994:409–438.

Gregory GA, Pediatric anesthesia4th ed. New York: Churchill Livingstone, 2002:522–524.

Kaplan JA, Reich DL, Konstadt SN, Cardiac anesthesia4th ed. Philadelphia: WB Saunders, 1999:801–813.

A.4. What is congenitally corrected TGA?

Congenitally corrected TGA is a type of congenital heart disease in which discordance exists between the atria and the ventricles as well as between the ventricles and great arteries. The two errors in alignment of the chambers and arteries ultimately leads to normal physiologic circulation. The atria and the ventricles align incorrectly as do the great vessels and the ventricles. Deoxygenated blood travels from the right atrium into the left ventricle and out into the pulmonary arteries. Similarly, oxygenated blood returns from the lungs into the left atrium into the RV and then is pumped into the aorta.

Associated findings include VSD, subpulmonic stenosis, AV valve regurgitation, and complete heart block.

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Casteñada AR. Jonas RA. Mayer JE, et al.Cardiac surgery of the neonate and infant Philadelphia: WB Saunders, 1994:443.

Friedman WF. Silverman N. Congenital heart disease in infancy and childhood. Braunwald E, Zipes D, Libby P, Heart disease: a textbook of cardiovascular medicine6th ed. Philadelphia: WB Saunders, 2001:1571.

Van Praagh R. Papagiannis J. Grunenfelder J, et al.Pathologic anatomy of corrected transposition of the great arteries: medical and surgical implications. Am Heart J 1998:135:772–785.

A.5. What are the preoperative issues pertaining to the coronary arteries?

In the normal pattern of coronary anatomy, the ostia arise from the sinuses of Valsalva, facing anteriorly toward the pulmonary artery.

In TGA, the coronary ostia continue to face the pulmonary artery, but the pulmonary artery is located posterior to the aorta. The coronary anatomy can be highly variable, both in how the coronary arteries are positioned on the aorta and how they branch. In almost all cases, the two coronary ostia face each other across the aorta—one ostium anterior and the other posterior. When the great vessels are side by side, the ostia are shifted so they are leftward/anterior and rightward/posterior facing.

In 20% of cases, the circumflex artery arises from the right coronary artery. A single coronary artery can occur in 6% of patients. Occasionally, the arteries can be inverted or intramural, making the surgical correction of this disease more complex.

The significance of these coronary artery patterns is their effect on surgical correction of d-TGA. A successful repair of transposition using the arterial switch procedure depends on a coronary artery pattern that can be easily translocated. Technical modifications in coronary reimplantation have minimized coronary artery pattern-related risks.

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Blume ED. Evolution of risk factors influencing early mortality of the arterial switch operation. J Am Coll Cardiol 1999:33:1702–1709.

Brown JW. Arterial switch operation: factors impacting survival in the current era. Ann Thorac Surg 2001:71:1978–1984.

Casteñada AR. Jonas RA. Mayer JE, et al.Cardiac surgery of the neonate and infant Philadelphia: WB Saunders, 1994:409–438.

Hutter PA. Influence of coronary anatomy and reimplantation on the long-term outcome of the arterial switch. Eur J Cardiothorac Surg 2000:18:207–213.

A.6. What are the clinical variations of d-TGA?

The most common variety of transposition as discussed previously is simple transposition or d-transposition. The right atrium is connected to the RV, which is in turn connected to the aorta. The left atrium is connected to the left ventricle, which is connected to the pulmonary artery. The term "d" relates to the position of the aortic and pulmonic valves. In more than 80% of cases the aortic valve is spatially to the right of the pulmonary valve hence the use of the d (dextro).

d-TGA can be divided into four categories:

  • TGA with VSD

  • TGA with intact ventricular septum (IVS)

  • TGA with left ventricular outflow tract obstruction (LVOTO)

  • TGA with PVOD

Half of the patients with simple d-TGA have no additional cardiac abnormality with the exception of a PFO or PDA. Less commonly associated findings are tricuspid and mitral valve abnormalities and coarctation or hypoplasia of the aorta.

Double-outlet RV may also be seen with TGA—Taussig-Bing anomaly.

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Snider AR. General echocardiographic approach to the adult with suspected congenital heart disease. Otto CM, The practice of clinical echocardiography Philadelphia: WB Saunders, 1997:675.

A.7. What is the differential diagnosis of TGA and how is the diagnosis made?

Children with TGA and IVS present with cyanosis at birth. Patients with d-TGA and VSD or a large PDA can be missed initially and present in congestive failure at 2 to 3 weeks of age.

Cyanotic congenital heart disease presenting at birth falls into the classification of 5 Ts:

  • Tetralogy of Fallot

  • TGA

  • Tricuspid atresia

  • Truncus arteriosus

  • Total anomalous pulmonary venous return

Other cyanotic lesions included in the differential diagnosis are

  • Single ventricle

  • Hypoplastic left heart syndrome

  • Double-outlet RV

  • Single atrium

  • Pulmonic stenosis or atresia

Chest x-ray findings may suggest the abnormal pattern of the great arteries.

Findings include an egg-shaped heart, narrow superior mediastinum with small thymic shadow, and increased pulmonary vascular markings. Electrocardiogram (ECG) shows a right axis deviation and right ventricular hypertrophy. Unfortunately, both sets of ECG findings can be viewed as normal in the newborn.

The "gold standard" for diagnosis is two-dimensional and Doppler echocar-diography. With this, the anatomy is clearly visible. Echocardiography shows the aorta arising from the RV and the pulmonary artery from the left ventricle. Size, location, and degree of mixing can also be visualized. The coronary anatomy can frequently be adequately defined. The size, thickness, and mass of the left ventricle can be assessed as well as position of the ventricular septum—all important in the decision of how and when to approach the surgical repair.

Cardiac catheterization provides similar information but is more invasive than echocardiography. Additional information about the coronary anatomy and pulmonary vascular resistance (PVR) can be learned but is not always necessary for surgery. Most notably, catheterization can provide both the diagnosis and the opportunity to intervene to stabilize the patient.

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Frommelt MA. Advances in echocardiographic diagnostic modalities for the pediatrician. Pediatr Clin North Am 1999:46:427–439.

Hornung TS. Should we standardize the pre-operative management of babies with complete transposition?. Cardiol Young 2000:10:458–460.

Tonkin IL. Kelley MJ. Bream PR, et al.The frontal chest film as a method of suspecting transposition complexes. Circulation 1976:53:1016–1025.

A.8. What preoperative interventions can help stabilize the patient?

Patients with d-TGA are dependent on mixing between the systemic and pulmonary circulation for survival. In the absence of an ASD or VSD, measures need to be taken to maintain the ductus arteriosus. Prostaglandin E1 (PGE1) will both increase PBF and enhance mixing of blood. PGE1 may cause apnea and low-grade fever; thus, cardiac and respiratory monitoring are needed. If the prostaglandin infusion does not provide adequate mixing, a balloon atrial septostomy procedure can be performed.

Rashkind and Miller first described balloon atrial septostomy in 1966 as a palliative procedure for TGA. This procedure removes the atrial septum. Obstruction to flow across the atrial septum is alleviated and bidirectional mixing of the pulmonary and systemic venous blood occurs freely. This improves oxygen saturation and leads to dramatic improvement in the infant's hemodynamic and symptomatic status. The efficacy and safety of this procedure have been repeatedly demonstrated. Conventionally, the procedure is performed in the catheterization laboratory under fluoroscopic guidance. Several studies have demonstrated the safety of bedside septostomy under echocardiographic guidance. The indications for blade septostomy are the same as for balloon septostomy.

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Beitzke A. Balloon atrial septostomy under two-dimensional echocardiographic control. Int J Cardiol 1991:30:33–42.

Komai H. The benefits of surgical atrial septostomy guided by transesophageal echocardiography in pediatric patients. J Thorac Cardiovasc Surg 1999:118:758–759.

Pihkala J. Interventional cardiac catheterization. Pediatr Clin North Am 1999:46:441–464.

Rashkind WJ. Transposition of the great arteries. Results of palliation by balloon atrioseptostomy in thirty-one infants. Circulation 1968:38:453–462.

Ward CJ. Minimally invasive management of transposition of the great arteries in the newborn period. Am J Cardiol 1992:69:1321–1323.

A.9. What determines the oxygen saturation in patients with TGA and why?

Hemodynamic stability and oxygen saturation are determined primarily by the amount of circulatory mixing. The greater the quantity of shunted blood in relation to recirculated blood, the higher the oxygen saturation. Number, size, and position of mixing sites affect the degree of circulatory crossover. A single unrestricted communication allows more mixing than multiple restrictive communications.

Mixing must be bidirectional with shunts going right to left and left to right. Changes in PVR or systemic vascular resistance (SVR), ventricular compliance, or cardiac output can affect the degree of crossover.

Patients who have a decreased amount of PBF resulting from outflow obstruction can also have severe hypoxemia. Patients who have a large VSD may have a large amount of PBF, early pulmonary hypertension, and evidence of congestive heart failure (CHF).

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Casteñada AR. Jonas RA. Mayer JE, et al.Cardiac surgery of the neonate and infant Philadelphia: WB Saunders, 1994:409–438.

Kaplan JA, Reich DL, Konstadt SN, Cardiac anesthesia4th ed. Philadelphia: WB Saunders, 1999:801–813.

Lake CL, Pediatric cardiac anesthesia3rd ed. Stamford, CT: Appleton & Lange, 1998:315–335.

A.10. Discuss the development of pulmonary vascular occlusive disease (PVOD) in patients with d-TGA.

Patients with uncorrected d-TGA rapidly develop PVOD. Although it is not well understood, the causes are thought to be the increase in PBF, pulmonary hypertension, and high pulmonary arterial PO2. Systemic hypoxemia, bronchopulmonary collaterals, and reduced saturation of bronchial arterial blood are thought to be additional contributing factors. The rapidity with which this develops can be seen in patients who have d-TGA and VSD.

PVOD is important because pulmonary hypertension limits the available methods for surgical correction. The ASO must be performed before the development of PVOD.

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Casteñada AR. Jonas RA. Mayer JE, et al.Cardiac surgery of the neonate and infant Philadelphia: WB Saunders, 1994:409–438.

A.11. What are the surgical options for repair? Why is one chosen over the others?

The current repair of choice for d-TGA is the ASO. An atrial level repair with either a Senning or a Mustard procedure is an older surgical technique. The atrial level repair is no longer preferred because of associated atrial arrhythmias, baffle obstruction, and late deterioration of the morphologic RV facing the pressure work of the systemic circuit.

Arterial Switch Operation (ASO)

The major advantage of the arterial switch procedure, when compared with the atrial switch procedure, is restoration of the left ventricle as the systemic pump.

Normal cardiac muscle development after birth includes a 25% reduction in right ventricular muscle mass and a 30% increase in LV muscle mass as soon as a baby is born. In d-TGA, the RV faces the systemic circulation and the left ventricle faces the lower resistance pulmonary vascular bed. The expected increase in LV mass does not occur because the volume and pressure stimuli for growth are not present for the left ventricle. Because it faces the lower resistance of the pulmonary circulation, the left ventricle is unable to support the systemic circulation after several weeks. In contrast, the RV increases its mass in response to the needs of the systemic circuit.

The importance of these changes or lack of changes is seen in the response of the heart to the arterial switch procedure.

Timing of surgical intervention depends on the age of the patient and the presenting variant of d-TGA. TGA with IVS undergoes an arterial switch procedure within the first 2 weeks of life before the left ventricle loses the necessary mass to tolerate the procedure. In the event that the surgery is delayed for other neonatal disease states that require intervention first, a two-staged repair can be performed. The first stage is to band the pulmonary artery and place a modified Blalock-Taussig (B-T) shunt to sustain adequate PBF. This subjects the left ventricle to the necessary pressure load to activate the regulatory genes responsible for production of myocardial actin, myosin, and tropomyosin. After several days to a week of preparation, the ASO is performed.

Patients with d-TGA and VSD face the same time pressure to undergo a complete repair. Instead of concerns regarding the ventricular strength and muscle mass, the race is against the development of PVOD. The pressure load that the left ventricle faces from exposure to the RV across the VSD keeps the left ventricle from undergoing the changes seen in TGA with IVS.

Atrial Inversion Operations

Historically, early operations for d-TGA consisted of some form of atrial switch procedure (Mustard or Senning operation). Although these procedures produced excellent early survival (about 85% to 90% survival) they ultimately resulted in significant long-term morbidity. The atrial switch procedures involve significant atrial surgery and may result in the late development of atrial conduction disturbances, sick-sinus syndrome with bradyarrhythmias and tachyarrhythmias, atrial flutter, sudden death, superior or inferior vena cava syndrome, edema, ascites, and protein-losing enteropathy.

Given the excellent short- and long-term results following the ASO, the Senning or Mustard procedures are only used in those patients that have unswitchable anatomy because of abnormal coronary artery location or branching.

Rastelli Operation

A third surgical option for correction of transposition is the Rastelli operation. The anatomic requirements for a Rastelli operation are d-TGA, a large VSD, and LVOTO.

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Berstein D. Cyanotic cogenital heart disease: lesions associated with increased pulmonary blood flow. Behrman RE, Kliegman R, Jenson HB, eds, Nelson textbook of pediatrics16th ed. Philadelphia: WB Saunders, 2000:1397.

Friedman WF. Silverman N. Congenital heart disease in infancy and childhood. Braunwald E, Zipes D, Libby P, Heart disease: a textbook of cardiovascular medicine6th ed. Philadelphia: WB Saunders, 2001:1570.

Mee RB. Drummond-Webb JJ. Congenital heart disease. Townsend CM, Sabiston textbook of surgery6th ed. Philadelphia: WB Saunders, 2001:1253.

Peterson KL. Reitz BA. Yuh DD. Pediatric cardiovascular surgery. Jaffe RA, Samuels SI, Anesthesiologist's manual of surgical procedures2nd ed. Philadelphia: Lippincott Williams & Wilkins, 1999:911.

B. Preoperative Evaluation and Preparation

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B.1. What information is important to prepare for this case?

The preoperative evaluation should begin with a careful history and physical examination. Gestational age, birth complications, family history, and any other medical problems should be noted. An evaluation of the airway is critical. Arterial and intravenous access should be noted as well.

The patient's course including hemodynamic data, oxygen saturations, vasoactive infusions, and medical or surgical interventions are needed. If a cardiac catheterization was performed, data noting ventricular function, the anatomy of the coronary arteries, and any areas of mixing should be available.

Laboratory data should include a complete blood count, electrolytes, platelet count, arterial blood gas, calcium, blood urea nitrogen (BUN), creatinine, and glucose. An ECG and chest x-ray film should be performed. A type and cross must be sent to the blood bank to ensure that adequate blood and blood products are available in the operating room.

Frequently, an extensive neurologic examination is undertaken after balloon septostomy because of the possibility of emboli during the procedure.

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Boyer KM. RSV and the timing of surgery for congenital heart disease. Crit Care Med 1999:27:2065–2066.

Casteñada AR. Jonas RA. Mayer JE, et al.Cardiac surgery of the neonate and infant Philadelphia: WB Saunders, 1994:409–438.

Kaplan JA, Reich DL, Konstadt SN, Cardiac anesthesia4th ed. Philadelphia: WB Saunders, 1999:801–813.

Khongphatthanayothin A. Impact of respiratory syncytial virus infection on surgery for congenital heart disease: postoperative course and outcome. Crit Care Med 1999:27:1974–1981.

B.2. What will we do as anesthesiologists to make things better or worse?

Ensuring that the patient is appropriately prepared before surgery can make the intraoperative management less stressful and much smoother. Adequate volume and metabolic states contribute to hemodynamic stability. Necessary inotropic or PGE1 infusions should be started and maintained into the operating room.

Much of what anesthesiologists routinely do in the pre-CPB period can destabilize the patient. Alterations in the relationship of SVR to PVR can alter the degree of mixing and subsequently the oxygen saturation. Increases in PVR can diminish PBF from bronchopulmonary collateral vessels or the PDA.

Induction techniques should aim for hemodynamic stability with minimal myocardial depression. Right ventricular function is a concern throughout the prebypass period.

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Lake CL, Pediatric cardiac anesthesia3rd ed. Stamford, CT: Appleton & Lange, 1998:315–335.

B.3. How would you prepare your operating room?

Preparing the operating room is similar to that of most cases. The anesthesia machine should be checked and set with a neonatal or pediatric circuit. Pediatric laryngoscopes and endotracheal tubes should be ready. A heat/moisture exchanger or humidifier should be included in the circuit.

Suction must be readily available.

Two intravenous lines should be carefully prepared to eliminate all air bubbles from the tubing.

The room should be warmed and a warming blanket available.

Blood must be in the operating room before commencement of surgery.

Emergency drugs should be prepared in unit doses so they can be administered without having to calculate dose.

Epinephrine 10 g/kg

Calcium chloride 10 mg/kg

Atropine 20 g/kg

Heparin 300 to 400 units/kg

Lidocaine 1 mg/kg

Phenylephrine 1 to 2 g/kg

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Lake CL, Pediatric cardiac anesthesia3rd ed. Stamford, CT: Appleton & Lange, 1998:315–335.

C. Intraoperative Management

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C.1. How would you monitor this baby?

Standard monitors include blood pressure, capnography, ECG with ST analysis, temperature, and pulse oximetry. Monitoring of urine output is important in all patients requiring CPB.

All cardiac patients need to have an arterial line placed. The location of this line can be institution dependent. The line must be reliable because it will be required for several days postoperatively. An umbilical, radial, femoral, or axillary arterial approach may be taken.

A central line may be placed preoperatively. An alternative to percutaneous placement preoperatively is to have the surgeon place a transthoracic line before separation from CPB. Transesophageal echocardiography (TEE) can also be useful to evaluate ventricular function and volume status, and to detect any residual shunts after the repair. It can also be used to detect ischemia with the presence of new wall motion abnormalities.

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Kaplan JA, Reich DL, Konstadt SN, Cardiac anesthesia4th ed. Philadelphia: WB Saunders, 1999:801–813.

Lake CL, Pediatric cardiac anesthesia3rd ed. Stamford, CT: Appleton & Lange, 1998:315–335.

C.2. What would be the best method of induction?

Almost all patients with TGA come to the operating room with intravenous access. They often require infusions of inotropes and/or PGE1. Frequently, they are intubated.

An intravenous narcotic technique with fentanyl (50 to 100 g/kg) or sufentanil (10 to 15 g/kg) is safe. Neither narcotic causes myocardial depression. Both are hemodynamically stable and blunt pulmonary reactivity.

Cardiac output in neonates is heart rate dependent. Pancuronium (0.1 mg/kg) is used as the muscle relaxant to increase heart rate. It offsets the bradycardia seen with narcotic inductions.

Midazolam (0.1 to 0.3 mg/kg) can be used for amnesia; however, it can cause a decrease in vascular resistance when combined with narcotics.

Inhalational anesthetics can also be used.

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Kaplan JA, Reich DL, Konstadt SN, Cardiac anesthesia4th ed. Philadelphia: WB Saunders, 1999:801–813.

Lake CL, Pediatric cardiac anesthesia3rd ed. Stamford, CT: Appleton & Lange, 1998:315–335.

C.3. What are the pre-cardiopulmonary bypass (pre-CPB) issues?

The goals of prebypass management are

  • Maintain preload, cardiac output, and heart rate

  • Avoid myocardial depression

  • Maintain or decrease PVR

  • Avoid reductions in SVR

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Casteñada AR. Jonas RA. Mayer JE, et al.Cardiac surgery of the neonate and infant Philadelphia: WB Saunders, 1994:409–438.

Lake CL, Pediatric cardiac anesthesia3rd ed. Stamford, CT: Appleton & Lange, 1998:315–335.

C.4. Is CPB in pediatrics different from adults?

The general principles of CPB are the same for children and adults. The differences are seen in flow rates, perfusion pressures, anatomic considerations, and equipment. Because of their small size, infants and neonates undergo significant hemodilution by the priming volume of the CPB circuit. Hemodilution affects red cell mass, coagulation factors, and drug levels.

CPB requires aortic and bicaval cannulation. In the rare instance of an interrupted aortic arch, two aortic cannulae are necessary. A persistent left superior vena cava may be present and must be adequately drained on CPB.

Pump flow rates vary with the size of the patient ranging from 200 mL/kg/minute in the neonate to 100 mL/kg/minute in older infants and children.

Perfusion pressure is lower than in adults with mean arterial pressure ranging from 30 to 50 mm Hg.

Infants and children have a high ratio of surface area to body weight. Warming and cooling on bypass occur much more rapidly.

Increased noncoronary collateral flow can cause problems with myocardial protection. This may cause cardioplegia washout and early rewarming of the myocardium.

Deep hypothermia (with or without circulatory arrest) and profound hemodilution are fairly standard practice in pediatric perfusion. Systemic hypothermia allows reduced flow rates, and myocardial collateral flow is decreased.

Other approaches to try to minimize transfusion requirements have focused on preservation of platelet function and prevention of fibrinolysis, using drugs such as -aminocaproic acid and aprotinin. Although the data are fairly convincing in support of decreased transfusion requirements in reoperations in adults, the data are not as clear in infants.

The process of weaning from CPB is no different in children than in adults. The infant myocardium is much more dependent on ionized calcium for adequate function.

Decreasing PVR is important for a successful wean from CPB.

Left ventricular dysfunction can also be a problem. Unfortunately, the options for mechanical assist devices are not as varied for children as for adults. Other options for failure to wean from CPB include extracorporeal membrane oxygenation (ECMO) or placement of a ventricular assist device.

In 1993, Naik and Elliott described a technique of modified ultrafiltration (MUF) that is performed in the immediate postbypass period. Blood is siphoned from the aorta, pumped through a hemoconcentrator, and returned to the right atrium. Multiple studies have documented the effectiveness of MUF in ameliorating many of the adverse effects of CPB. MUF improves hemodynamics, reduces total-body water, and decreases the need for blood transfusions compared with nonfiltered controls.

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Davies LK. Cardiopulmonary bypass in infants and children: how is it different?. J Cardiothorac Vasc Anesth 1999:13:330–345.

Davies MJ. Modified ultrafiltration improves left ventricular systolic function in infants after cardiopulmonary bypass. J Thorac Cardiovasc Surg 1998:15:361–369. discussion

Elliott MJ. Ultrafiltration and modified ultrafiltration in pediatric open-heart operations. Ann Thorac Surg 1993:56:1518–1522.

Greeley WJ. Steven JM. Nicolson SC, et al.Anesthesia for pediatric cardiac surgery. Miller RD, Anesthesia5th ed. New York: Churchill Livingstone, 2000:1821–1834.

Weinhaus L. Extracorporeal membrane oxygenation for circulatory support after repair of congenital heart defects. Ann Thorac Surg 1989:48:206–212.

C.5. How does the surgeon correct this lesion?

The heart is exposed through a standard median sternotomy and CPB is instituted with the patient being cooled to 18°C. After administration of cardioplegia, the corrective surgery commences.

Atrial Baffle Procedure (Mustard and Senning)

The atrial inversion surgery partitions the atria, forcing oxygenated venous return from the pulmonary veins to empty into the RV across the tricuspid valve. At the same time, redirection of deoxygenated blood to the left ventricle occurs by baffling systemic venous return across to the mitral valve. Because the aorta arises from the RV and the pulmonary artery from the left ventricle, switching the venous return results in a physiologic but nonanatomic correction of d-TGA. The Mustard procedure uses pericardium to baffle flow in the atrium. The Senning operation uses all native atrial tissue to accomplish the same hemodynamic effects.

The atrial inversion operation leaves the RV as the dominant chamber to power the systemic circulation.

Figure 10.3. The arterial switch procedure. A: First, the pulmonary artery and aorta are transected just above their respective valves. The coronaries are excised and mobilized from the ascending aorta with a button of surrounding tissue and then reimplanted into the proximal pulmonary artery (neoaorta) (A and B). C: The great arteries are then switched: the distal pulmonary artery is brought anterior to the ascending aorta (right ventricular outflow) and the distal aorta is moved posteriorly where it is anastomosed to the proximal pulmonary artery (left ventricular outflow) just above the reimplanted coronary arteries. D: The donor sites of the excised coronary arteries in the proximal aorta are repaired with either pericardium or synthetic material. Finally, anastomosis of the proximal aorta and distal pulmonary artery is completed. (From Castaned AR, Norwood WI, Jonas RI, et al. Transposition of the great arteries and intact interventricular septum: anatomical repair in the neonate. Ann Thorac Surg 38:440, 1984, with permission.)


Arterial Switch Operation (ASO)

Also known as the Jatene procedure, the ASO solves the circulatory problems both anatomically and physiologically. The ascending aorta is transected at its midportion and the pulmonary trunk is transected just proximal to its bifurcation. Two buttons of tissue containing the origins of the left and right coronary arteries are transposed from the former aortic root and anastomosed to the former main pulmonary trunk. The distal aortic segment is swung beneath the pulmonary artery bifurcation (LeCompte maneuver). Pericardial patches are used to repair the defects resulting from excision of the coronary artery buttons. Any associated ASDs and/or VSDs are repaired. The distal aortic segment is anastomosed to the former proximal pulmonary artery and the distal bifurcated pulmonary artery segment is anastomosed to the former proximal aorta (Fig. 10.3).

Success of the ASO depends on the age of the patient and the preparation the left ventricle has undergone in anticipation of the pressure load it will face as the systemic ventricle.

Rastelli Procedure

The Rastelli procedure is a ventricular inversion procedure that can only be performed in patients with d-TGA and a large VSD. The outflow from the left ventricle is directed across the VSD and out the aortic valve into the aorta. The pulmonary valve on the left ventricle is oversewn and a conduit connects the RV to the pulmonary artery.

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Casteñada AR. Jonas RA. Mayer JE, et al.Cardiac surgery of the neonate and infant Philadelphia: WB Saunders, 1994:409–438.

C.6. What is hypothermia and how is it classified? Circulatory arrest? Low-flow CPB?

Hypothermia is a routine part of CPB. To accomplish significant hypothermia, a CPB circuit is usually used. A cooling blanket, cold ambient temperatures, and ice packs (placed around the head) are also used to prevent heat from seeping into the patient. Cooling is a nonuniform process. As such, multiple sites are used to measure temperature to ensure as little variability in body temperature as possible. Duration of cooling is significant in limiting temperature variability.

Three types of hypothermia are used in cardiac surgery:

  • Mild hypothermia: more than 32°C

  • Moderate hypothermia: 25°C to 32°C

  • Deep hypothermia: 15°C to 20°C

The degree of hypothermia used depends on the complexity of the surgery, the requirements of a bloodless field, and the patient's size. Mild and moderate hypothermia are used routinely for most pediatric and adult cardiac surgical procedures.

Deep hypothermia is reserved for cases that involve the aortic arch or its branches that provide blood flow to the brain. It is generally used for neonates and infants requiring complex cardiac repair. Hypothermia has been shown to be protective to ischemic organs—specifically the brain. For the most part, deep hypothermia is selected to allow the surgeon to operate under conditions of low-flow CPB or total circulatory arrest.

Circulatory arrest is achieved when the patient is cooled to 18°C and CPB is terminated for a period. Blood is drained from the patient into the bypass circuit and recirculated within the pump. The cannulae are removed from the patient and the surgical field is bloodless. When the critical portions of the surgery are completed, bypass is reinstituted and the patient is rewarmed.

Low-flow CPB is defined by flow rates of 30 to 40 cc/kg/minute. It is an alternative to total circulatory arrest when the cannulae or blood in the field are tolerable for the surgeon. Low-flow CPB is thought to be better for patients because it preserves high-energy phosphates and intracellular pH.

The neurologic risk associated with circulatory arrest is related to cerebral hypoxic and ischemic insults. Adding to that initial injury is the effect of reperfusion on ischemic tissue. Compared with low-flow bypass, circulatory arrest patients have longer electroencephalographic (EEG) recovery times, greater levels of brain-specific creatine kinase (CK) enzyme release, and a higher incidence of seizures postoperatively. In addition, there seems to be a higher prevalence of neurologic abnormalities, poor motor development, and expressive language difficulties in patients undergoing circulatory arrest as compared to low-flow bypass patients.

A comparison of both hemodynamic data and non-neurologic postoperative course between patients undergoing circulatory arrest and low-flow bypass show similar results.

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Bellinger DC. Wypij D. Kuban KCK, et al.Developmental and neurological status of children at 4 years of age after heart surgery with hypothermic circulatory arrest or low-flow cardiopulmonary bypass. Circulation 1999:100:526–532.

Greeley WJ. Steven JM. Nicolson SC, et al.Anesthesia for pediatric cardiac surgery. Miller RD, Anesthesia5th ed. New York: Churchill Livingstone, 2000:1823.

Kaplan JA, Reich DL, Konstadt SN, Cardiac anesthesia4th ed. Philadelphia: WB Saunders, 1999:801–813.

Wernovsky G. Wypij D. Jonas RA, et al.Postoperative course and hemodynamic profile after the arterial switch operation in neonates and infants. A comparison of low-flow cardiopulmonary bypass and circulatory arrest. Circulation 1995:92:2226–2235.

C.7. What are the physiologic changes and potential complications associated with hypothermia?

The goal of hypothermia is to afford organ protection by reducing cellular metabolism and thereby preserving high-energy phosphate (ATP) stores. Hypothermia decreases metabolism as long as shivering is prevented. Shivering can increase whole-body metabolic demand by severalfold. It can be prevented by the use of muscle relaxants and sedatives. Hypothermia induces the following physiologic changes:

  • Oxygen delivery and acid-base status. The oxygen-hemoglobin dissociation curve is shifted to the left, which reduces the release of oxygen from hemoglobin. There is an increase in the solubility of oxygen, carbon dioxide, and anesthetic gases in the blood. If perfusion, and therefore cooling, is not uniform then metabolic acidosis may occur.

  • Hematologic. Increase in blood viscosity (offset by the hemodilution of bypass), prolongation of prothrombin time and bleeding time, and decrease in fibrinogen activity.

  • Cardiovascular. Initial cooling results in vasoconstriction and increase in SVR. Heart rate progressively slows as cooling continues. Electrocardiographic changes include prolongation of the PR, QRS, and QT intervals. Nonspecific ST- and T-wave changes may be observed. The J-wave is a characteristic electrocardiographic change associated with hypothermia (at about 30°C) and consists of a small positive wave on the downstroke of the R-wave. Cardiac output decreases as the heart rate slows; stroke volume is not significantly changed above a temperature of 25°C.

  • Hepatic and renal. Hepatic function decreases as hypothermia ensues and drug metabolism is significantly reduced. Glucose and citrate are not metabolized. As temperature and cardiac output fall, renal blood flow decreases. This is in part due to the release of renin, angiotensin, and antidiuretic hormone. Tubule reabsorption decreases because of cold-induced inhibition of transport mechanisms. Urinary output may be maintained down to 20°C, however, below this temperature, urine production stops.

  • Endocrine. Epinephrine, adrenal cortical steroids, and adrenocorticotropic hormone (ACTH) levels increase with hypothermia, indicating that it induces a stress response.

Potential complications include tissue ischemia and irreversible damage to peripheral tissues such as the nose, fingers, toes, external genitalia, and ears.

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Gravlee GP, Davis RF, Krursz M, et al., Cardiopulmonary bypass: principles and practice2nd ed. Philadelphia: Lippincott, Williams & Wilkins, 2000:197–214.

C.8. What parameters are measured on CPB?

  • Perfusion pressure is usually maintained between 30 to 50 mm Hg.

  • Blood gases are monitored every 20 to 30 minutes while on CPB to ensure adequate gas exchange and perfusion. Hematocrit can be assessed at this time and corrected if it falls below acceptable levels (25% to 30%). Respiratory acidosis is corrected by increasing the gas sweep through the oxygenator, and metabolic acidosis is corrected with sodium bicarbonate.

  • Mixed venous oxygen saturation (MVO2) can be used to determine adequate tissue perfusion. A decrease in MVO2 can reveal poor perfusion, light anesthesia, or increased oxygen consumption.

  • Urine output should be 1 to 2 mL/kg/hour.

  • Temperature is monitored with a rectal, tympanic, and nasopharyngeal probe. Patients are cooled to 18°C while on bypass.

  • Activated clotting time (ACT) indicates the level of anticoagulation. An ACT is repeated every 20 to 30 minutes after heparin administration to ensure an adequate degree of anticoagulation (ACT greater than 480 seconds) for CPB. If necessary, additional heparin is administered.

  • Glucose, potassium, and calcium are measured throughout the bypass period. Glucose is measured to prevent inadvertent hypoglycemia and to allow treatment of hyperglycemia as well. Hyperglycemia at the time of neurologic injury can worsen outcome. Cardioplegia relies on potassium to abolish the electrical gradient across the myocardial membrane. The potassium in cardioplegia can raise serum potassium levels above normal and affect myocardial conduction and contractility. The infant myocardium is particularly sensitive to ionized calcium levels. Low ionized calcium levels can impair contractility and separation from CPB.

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Hensley FA Jr, Martin DE, A practical approach to cardiac anesthesia2nd ed. Philadelphia: Little, Brown and Company, 1995:345–346.

Lake CL, Pediatric cardiac anesthesia3rd ed. Stamford, CT: Appleton & Lange, 1998:315–335.

Miller RD, Anesthesia5th ed. Philadelphia: Churchill Livingstone, 2000:1821–1825.

C.9. What are the major issues when separating from CPB?

The major issues when separating from CPB concern cardiac and respiratory function.

Cardiac Function

During rewarming of the patient, the cross clamp is removed, normal coronary blood flow resumes, and a cardiac rhythm is restored. Sinus rhythm at a rate normal for the patient's age is optimal. In the event that this cannot be accomplished, atrial or atrial/ventricular pacing should be used.

Contractility, preload and afterload are other components that need to be optimized before and during separation from bypass. Because of the alterations in loading conditions of the ventricles, inotropic support is used when separating from CPB. Milrinone or dobutamine infusions are frequently chosen to improve contractility of the left ventricle and reduce SVR and PVR. Nitroglycerin is used as a coronary artery dilator and for reduction of left ventricular preload.

Preload is assessed by direct visualization of the heart and monitoring right atrial or left atrial filling pressures. Slow infusion of blood from the pump can be used to optimize filling pressures.

Inadequate cardiac function following the ASO can result from inadequate myocardial protection, an inappropriately prepared left ventricle, myocardial ischemia from inadequate coronary perfusion, or excessively long periods of aortic cross clamp. Ischemia can result from kinking of the coronary arteries or coronary air emboli.

Residual shunt and pulmonary hypertension can contribute to poor cardiac function. TEE is used to provide image of the postoperative cardiac repair and function of the left ventricle.

Pulmonary Function

Adequate ventilation is critical to a successful separation from bypass. Inspiratory pressures are frequently higher after bypass than during the prebypass period because of a decrease in pulmonary compliance associated with CPB. Hyperventilation can assist in lowering PVR.

Poor pulmonary function can result from inadequate ventilation, atelectasis, pneumothorax, or inadequate PBF.

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Greeley WJ. Steven JM. Nicolson SC, et al.Anesthesia for pediatric cardiac surgery. Miller RD, Anesthesia5th ed. New York: Churchill Livingstone, 2000:1829.

Lake CL, Pediatric cardiac anesthesia3rd ed. Stamford, CT: Appleton & Lange, 1998:315–335.

C.10. What are the immediate post-CPB issues following ASO?

Myocardial ischemia is a major concern following separation from CPB. Coronary air embolism, difficulties with coronary implantation, or coronary artery spasm are the primary causes of immediate myocardial ischemia. ST segment analysis and detection of new wall motion abnormalities on TEE allow for its rapid detection. Ischemia can lead to ventricular dysfunction, mitral regurgitation, or a variety of arrhythmias.

LV dysfunction is also possible if the left ventricle has not been adequately prepared to support the systemic circulation. Inotropic support and afterload reduction may be necessary in the immediate postoperative period to support the struggling left ventricle.

Surgical closure of a VSD can result in transient or complete heart block.

Hypertension should be avoided after the surgical repair is complete to minimize hemodynamic causes of bleeding. Phosphodiesterase inhibitors or sodium nitroprusside infusions can help control systemic blood pressure. Hyperventilation and oxygenation can be used to lower PVR and pulmonary artery pressures.

Hypoxemia can persist when residual atrial or ventricular level shunting remains.

Bleeding after CPB can be a particular problem with some children. Dilutional coagulopathy from exposure to the pump prime is significant enough to warrant correction with platelet and fresh frozen plasma transfusions. A normal hematocrit for the patient's age is necessary to maintain oxygen carrying capacity and delivery to the body.

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Casteñada AR. Jonas RA. Mayer JE, et al.Cardiac surgery of the neonate and infant Philadelphia: WB Saunders, 1994:409–438.

Lake CL, Pediatric cardiac anesthesia3rd ed. Stamford, CT: Appleton & Lange, 1998:315–335.

D. Postoperative Management

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D.1. What are the management issues in the intensive care unit?

The issues surrounding myocardial ischemia and arrhythmias discussed previously remain for much of the postoperative period. Bleeding is an immediate concern that resolves within the first 12 hours after completion of surgery.

Seizures after CPB in neonates are much more common than in adults and occur clinically in approximately 20% of this population after CPB. The seizures are generally self-limited and can occur regardless of whether circulatory arrest is used. Postoperative seizures are associated with worsened neurologic outcomes and may be early manifestations of neurologic and developmental problems to come.

Adequate ventilation must be maintained to control PVR. Mechanical ventilation should be continued until the patient has shown stable hemodynamic parameters, absence of rhythm abnormalities, and normal coagulation.

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Lake CL, Pediatric cardiac anesthesia3rd ed. Stamford, CT: Appleton & Lange, 1998:315–335.

D.2. What is JET?

JET is junctional ectopic tachycardia, which is an uncommon tachycardia that is observed in the postoperative period following CPB in infants and toddlers with congenital heart disease. The classic electrocardiographic findings are a tachycardia with normal QRS complex and a rate of 180 to 240 beats/minute with AV dissociation. The etiology remains unknown but it is believed to be due to enhanced automaticity of tissues in or near the AV node as a result of surgical trauma.

The arrhythmia is usually transient in nature and is unusually resistant to most antiarrhythmic therapy. The hemodynamic instability associated with JET warrants aggressive intervention to slow the heart rate and, if possible, to restore sinus rhythm. Procainamide and propafenone have been used effectively but, because of their negative inotropic effects, may not be appropriate agents if the patient is hemodynamically unstable. Because of the lack of response and risks of other therapies, induced hypothermia has become the treatment of choice in treating postoperative JET. Cooling to a temperature of 31°C to 34°C has been shown to decrease the heart to below 180 beats/minute but may result in peripheral vasoconstriction, metabolic acidosis, and agitation. Postoperative JET is usually transient. The heart rate usually returns to normal sinus rhythm within 24 to 72 hours regardless of the intervention used. Refractory or prolonged JET in the postoperative period conveys poor prognosis.

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Emmanouilides GC, Riemenschneider TA, Allen HD, et al., Moss and Adams' heart disease in infants, children, and adolescents5th ed. Baltimore: Williams & Wilkins, 1995:1585–1587.

D.3. What are the surgical problems seen after correction of d-TGA?

Atrial Inversion

The atrial inversion operation has some unique postoperative complications. Stenosis of the atrial baffles can lead to obstruction of systemic and pulmonary venous return. This can result in pulmonary hypertension or superior vena cava syndrome. Reduction in venous return results in a low cardiac output.

Switching flow in the atrium corrects the abnormal physiology, but the discordance between the ventricles and great vessels remains. The RV, anatomically designed to pump large volumes into a low-pressure system, is now responsible for pumping its cardiac output into the high-pressure and high-resistance circuit of the systemic circulation. After many years of facing this pressure load, the RV can fail.

Tricuspid regurgitation is a concern because of the geometry of the RV. The RV is crescent shaped with multiple small papillary muscles that are not designed to withstand pressure like the mitral valve. The volume and pressure load faced by the RV causes dilatation and distortion of the tricuspid valve, leading to regurgitation.

Atrial dilation and surgical manipulation creates a high likelihood that atrial dysrhythmias will develop. Supraventricular tachycardia and sick sinus syndrome are the predominant rhythm disturbances and are often difficult to control. Permanent pacemakers and surgical correction of the atrial baffles with ablation of the atrial conduction system have been used in an attempt to control dysrhythmias unresponsive to maximal pharmacologic intervention.

Pulmonary or systemic venous congestion can result from restrictive flow through the atrial baffle. Because it uses native atrial tissue, the Senning repair may take longer to become restrictive over time than the Mustard operation.

Arterial Switch

Because of the extensive suture lines, stenosis of the aorta or pulmonary artery has been reported. Damage to the aortic valve during surgery can lead to aortic insufficiency.

Myocardial infarction can result from mobilization or anastomosis of the coronary arteries. Twisting or kinking of the arteries can also lead to ischemia. Myocardial infarction accounts for more than half of immediate postoperative deaths.

Postoperative bleeding and tamponade occur more frequently because of the multiple suture lines involving major vascular structures.

One of the late complications of the arterial switch procedure is coronary artery stenosis.

Rastelli

Immediate postoperative complications include heart block and residual VSDs.

Normal cardiac growth can lead to restricted flow through the VSD and resulting LVOTO. Right ventricular outflow obstruction can develop from conduit stenosis or obstruction. Initial follow-up of the Rastelli procedure show excellent results. However, long-term morbidity and mortality from conduit obstruction, LVOTO, and dysrhythmias have made this option less palatable.

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Gregory GA, Pediatric anesthesia4th ed. New York: Churchill Livingstone, 2002:522–524.

Kaplan JA, Reich DL, Konstadt SN, Cardiac anesthesia4th ed. Philadelphia: WB Saunders, 1999:801–813.

Kreutzer C. De Vive J. Oppido G, et al.Twenty-five-year experience with Rastelli repair for transposition of the great arteries. J Thorac Cardiovasc Surg 2000:120:211–223.

Pretre R. Tamisier D. Bonhoeffer P, et al.Results of the arterial switch operation in neonates with transposed great arteries. Lancet 2001:357:1826–1830.

Rappaport LA. Wypij D. Beliinger DC, et al.Relation of seizures after cardiac surgery in early infancy to neurodevelopmental outcome. Circulation 1998:97:773–779.

D.4. What are the long-term outcomes after repair of d-TGA?

The overall outcomes depend on the type of repair that was performed.

In experienced hands, the mortality associated with neonatal correction of d-TGA with the ASO is less than 5%. If the coronary anatomy is relatively normal, the mortality drops closer to 2%. Survival probability has been reported at 94% with reoperation necessary in 22% after 10-year follow-up.

Following atrial inversion surgery, the actuarial survival is 90% at 10 years and 80% at 20 years and 28 years. Seventy-six percent of survivors have a New York Heart Association (NYHA) I classification. Twenty percent are symptomatic and 5% are unable to work. The most common cause of death in this group of patients seems to be sudden death (7%). Right heart failure is evident on echocardiographic follow-up in almost 20% of patients. Only 3% of the follow-up group have clinical evidence of right ventricular failure.

Exercise tolerance in patients after ASO are near the low limit of normal at 91% of expected. The same tests in patients having undergone atrial inversion surgery are well below normal at 75% of expected. The decrease in exercise performance has been attributed to lower cardiac output from diminished stroke volume and a blunted heart rate response.

Neurodevelopmental outcomes showed no difference between atrial switch operation or ASO. Compared with normals or siblings, children undergoing surgery for transposition had more learning disabilities, a greater incidence of behavioral disorders, and higher rate of abnormal neurologic examinations.

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Ellerbeck KA. Smith ML. Holden EW, et al.Neurodevelopmental outcomes in children surviving d-transposition of the great arteries. J Dev Behav Pediatr 1998:19:335–341.

Paul MH. Wessel HU. Exercise studies in patients with transposition of the great arteries after atrial repair operations (Mustard/Senning): a review. Pediatr Cardiol 1999:20:49–55.

Reybrouck T. Eyskens B. Mertens L, et al.Cardiorespiratory exercise function after the arterial switch operation for transposition of the great arteries. Eur Heart J 2001:22:1052–1059.

Wilson NJ. Clarkson PM. Barrat-Boyes BG, et al.Long-term outcomes after the Mustard repair for simple transposition of the great arteries. 28 year follow-up. J Am Coll Cardiol 1998:32:758–765.