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The addition of an atrial septal defect (which is of little further physiologic significance) turns the condition into the pentalogy of Fallot.

Because resistance to right ventricular outflow exceeds the systemic vascular resistance, the shunt is right to left, resulting in desaturation of the blood and cyanosis.

Exercise tolerance is limited because of the inability to increase pulmonary blood flow.

Clinical presentation

Cyanosis and dyspnea on exertion are routinely seen in patients with tetralogy of Fallot. Children soon learn that by squatting, they can temporarily alleviate these symptoms.

Squatting increases the systemic vascular resistance, which decreases the magnitude of right - to -left shunt and causes an increase in pulmonary blood flow.

The cyanosis is seen at birth in 30% of the cases, by the first year in 30%, and later in childhood in the remainder. Polycythemia and clubbing accompany the cyanosis.

Cerebrovascular accidents and brain sepsis constitute the major threats to life because cardiac failure is rare.

Diagnosis

Physical examination reveals clubbing of the digits and cyanosis. A harsh systolic murmur of pulmonary stenosis is often heard.

Cardiac catheterization is important for determining the level of pulmonic outflow obstruction and the size of the main and branch pulmonary arteries.

Treatment depends on many variables, including the anatomy of the defect and the age of the child.

Total correction is undertaken after 2 years of age.

Controversy exists over whether the defect should be corrected before this age. Many believe that a palliative systemic -to -pulmonary (Blalock-Taussig) shunt should be done initially, followed by definitive correction later on.

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The risk of surgery depends on the age of the patient and the degree of cyanosis.

After correction, a dramatic improvement is usually seen.

G Transposition of the great arteries

Pathophysiology

Transposition of the great arteries (TGA) occurs when the aorta arises from the morphologic right ventricle and the pulmonary artery arises from the morphologic left ventricle. This results in two independent parallel circuits.

Survival depends on a communication between the right and left sides of the heart to allow mixing of

oxygenated and unoxygenated blood. This communication usually occurs across an atrial septal defect, although a patent ductus arteriosus or ventricular septal defect could also be present.

Diagnosis

Echocardiogram demonstrates a posterior vessel dividing into the right and left pulmonary arteries arising from the left ventricle.

Cardiac catheterization is reserved for infants with additional intracardiac or extracardiac anomalies or inadequate shunting.

Treatment

When inadequate shunting exists, balloon atrial septostomy is performed to increase the size of the interatrial communication and facilitate mixing of blood. Septostomy is followed by definitive surgical correction.

Operative procedures include:

Arterial switch division of the great arteries with transfer of the coronaries and proper anastamoses of the aorta to the left and pulmonary artery to the right ventricles.

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Study Questions for Part II

Directions: Each of the numbered items in this section is followed by several possible answers. Select the ONE lettered answer that is BEST in each case.

1.A 50 -year-old man is brought to the emergency room after falling 20 feet from a roof. He is complaining of dyspnea, and his blood pressure is 70/50 mm Hg. Breath sounds are diminished on the left, and there is tracheal deviation to the right. What is the best initial treatment for this patient?

A Chest radiograph B Close observation

C Needle decompression of the left chest

D Computed tomography (CT) scan of the thorax E Emergent surgical exploration

View Answer

2.A patient undergoes a left scalene node biopsy to rule out carcinoma of the lung. One hour later, the patient is cyanotic and dyspneic; a marked tachycardia is accompanied by decreased breath sounds on the left. Which step is most likely to improve the patient's condition?

A Blood transfusion

B Insertion of a right subclavian catheter and administration of intravenous fluids C Endotracheal intubation

D Insertion of a left chest tube E Re -exploration of the wound View Answer

3.A patient is brought to the emergency department with a stab wound to the right chest in the fourth intercostal space in the midaxillary line. The patient is hypotensive, complains of shortness of breath, and is found to have absent breath sounds on the right side of the chest. Which step should come next in the management of this patient?

A Chest radiograph

B Chest tube insertion C Needle thoracentesis

D Local wound exploration E Pericardiocentesis

View Answer

4. A tall, thin 19 -year-old male presents to the emergency department with sudden onset of chest pain, cough, and shortness of breath. Breath sounds are absent in the left chest. Which of the following is an indication for surgery ?

A Family history of recurrent spontaneous pneumothorax B Persistent air leak after 3 days of chest tube drainage C Identification of an apical bleb on chest CT

D Evidence of life -threatening respiratory compromise on initial presentation

E History of one prior episode successfully treated with conservative management on the contralateral side

View Answer

Questions 5–6

A chest radiograph of a 55 -year -old man involved in a high-speed motor vehicle accident shows a widened mediastinum and pneumomediastinum. Electrocardiogram shows sinus tachycardia with frequent premature ventricular contractions.

5. All of the following maneuvers are appropriate at this time except

AAortogram

BBronchoscopy

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C Continuous cardiac monitoring

D Left thoracotomy

E Endotracheal intubation

View Answer

6. Expected physiologic changes due to blunt chest trauma include all but which of the following?

AElevated PCO 2

BIncreased compliance

CElevated A -a gradient

DDecreased ventricular contractions

EElevated shunt fractions

View Answer

Questions 7–8

A 70 -year -old patient on antibiotic therapy for necrotizing bacterial pneumonia is found to have a large pleural effusion.

7.In addition to continued antibiotics, what should be the next step in management of this patient? A Sputum culture and sensitivity

B Chest tube insertion C Thoracentesis

D Thoracotomy and decortication E Rib resection and open drainage View Answer

8.A sample of pleural fluid is cloudy and thick, with a pH of 7.2. What should be the next therapeutic step? A Video-assisted thorascopic surgery with talc pleurodesis

B Chest tube drainage C Repeat thoracentesis

D Thoracotomy and decortication E Rib resection drainage

View Answer

9.A routine chest radiograph for a 55 -year-old man with a 50 pack -year smoking history shows a peripherally located 1.5-cm, noncalcified lesion of the upper lobe of the left lung. No evidence of this lesion appeared on a chest radiograph 5 years earlier. What should be the next step in this patient's management ?

A Observation with serial chest radiographs

BThoracotomy

CBronchoscopy

DBiopsy

ESputum cytology View Answer

10.A 35 -year-old man is involved in a high -speed motor vehicle collision. He arrives in the emergency room in respiratory distress. Radiographs taken during the initial evaluation reveal an air-fluid level in the left chest. Management includes all of the following except

AEstablishment of a secure airway

BImmediate placement of a nasogastric tube

CUrgent thoracotomy to repair the injury

DPlacement of adequate peripheral vascular access

EUrgent laparotomy to repair injury

View Answer

11. Which of the following forms of congenital heart disease is most common ? A Transposition of the great vessels

B Tetralogy of Fallot C Atrial septal defect

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D Patent ductus arteriosus

E Ventricular septal defect

View Answer

12.A 32 -year-old man is referred for a 1.0-cm lesion of the right upper lobe of the lung. The lesion appears calcified. Previous chest radiograph taken 1 year prior demonstrates the lesion to be present at the same size. Further workup and treatment would include which of the following?

A CT scan–guided biopsy B Radiation therapy

C Surgical excision D Antibiotics

E Observation with repeat chest x-ray View Answer

13.A 57 -year-old male patient with a 60 pack -year smoking history is referred for a 1.5-cm solitary mass in the right upper lobe. CT scan demonstrates no evidence of lymph node involvement. What should further workup or treatment include ?

A Radiation therapy B Open lung biopsy C Chemotherapy

D Right upper lobectomy

E Repeat chest x-ray in 6 months View Answer

14.A 22 -year-old female is referred for evaluation of a 2-cm posterior mediastinal mass discovered on routine chest radiograph. What is the most likely diagnosis ?

A Bronchogenic cyst B Lymphoma

C Neurogenic tumor D Thymoma

E Adenocarcinoma View Answer

15.A 78 -year-old previously healthy man is admitted to the emergency department complaining of angina, dyspnea, and near syncope. Electrocardiogram is normal, and a loud systolic murmur is heard in the

second right interspace with radiation to the carotids. What is the most likely diagnosis in this patient? A Myocardial infarction

BPericarditis

CMitral regurgitation

DAortic stenosis

EAortic insufficiency View Answer

16.Which of the following is not a risk factor for coronary artery disease ? A Hypertension

B Smoking C Diabetes

D Renal failure

E Hypercholesterolemia View Answer

17.A 72 -year-old female patient is admitted with unstable angina. Cardiac catheterization reveals severe triple -vessel coronary artery disease. The optimal treatment of this patient would include which of the following?

A Coronary artery bypass surgery B Observation

C Medical management (nitrates, β-blockers)

D Coronary angioplasty

E Tissue plasminogen activator View Answer

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18. A 72 -year-old patient with a history of syncope and dyspnea presents for evaluation for peripheral vascular surgery. Physical examination reveals a systolic crescendo–decrescendo murmur that radiates to the carotid arteries. As he is symptomatic, his diseased valve would typically have an area of less than which of the following?

A1 cm2

B1.5 cm2

C2 cm2

D3 cm2

E4 cm2 View Answer

19.A 29 -year-old man is evaluated for a cerebral vascular accident. Physical examination reveals a systolic ejection murmur at the left second interspace and a fixed split second heart sound. What is the most likely diagnosis ?

AVentricular septal defect

BAtrial septal defect

CMitral stenosis

DAortic insufficiency

EVentricular aneurysm

View Answer

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Answers and Explanations

1. The answer is C [Chapter 4, II A 2]. Hypotension, diminished breath sounds, and tracheal deviation are clinical signs of tension pneumothorax. This represents a surgical emergency and without treatment may rapidly become fatal. In this scenario, prompt needle decompression of the left chest is indicated, prior to

chest x-ray or other diagnostic studies that could delay treatment.

2. The answer is D [Chapter 4, I B 3 c]. Insertion of a left chest tube will most likely improve the patient's condition. The pleura of the lung lies immediately adjacent to the scalene fat pad. If the pleura is injured during scalene node biopsy, a resultant pneumothorax can cause the symptoms that developed in the patient described. Scalene node biopsy can also injure other nearby structures; for example, lymph duct structures, the brachial plexus, the vagus and phrenic nerves, and the subclavian vessels, resulting in corresponding symptoms.

A large wound hematoma could cause tracheal compression and airway compromise, but this is not described. Intubation with positive pressure ventilation will make the pneumothorax worse without a chest tube. While injury to the subclavian vessels could cause a hemothorax, a chest tube still needs to be inserted for evaluation. A pneumothorax is the more likely injury. With a suspected left -sided pneumothorax, a subclavian line should be inserted on the left because of the risk of producing a second right -sided pneumothorax.

3. The answer is C [Chapter 4, II A 2 b–c ]. The patient has signs and symptoms consistent with a tension pneumothorax. This life -threatening situation should be treated immediately by needle thoracentesis. A chest tube insertion should follow this maneuver. A chest radiograph is not necessary to confirm the diagnosis and will only delay treatment. Local wound exploration has no role in the management of stab wounds of the chest. Pericardiocentesis is the choice when evidence indicates pericardial tamponade.

4. The answer is E [Chapter 5, II B]. Indications for definitive surgical management of spontaneous pneumothorax include recurrence (ipsilateral or contralateral), persistent air leak greater than 7–10 days, and incomplete expansion of lung.

5–6. The answers are 5-D [Chapter 4, II A 5, 6; B 1, 2, 5, 6] and 6-B [Chapter 4, II A 6]. Causes for the chest radiograph and electrocardiographic findings are multiple and include aortic rupture, cardiac tamponade, tracheobronchial disruption, hypoxia, and cardiac contusion. A more precise diagnosis would be mandatory before undertaking thoracotomy because operative strategy would depend on which injury is present.

Blunt thoracic trauma with or without flail chest results in chest wall muscle damage and pain, with resultant splinting and loss of chest wall elasticity. Intra -alveolar hemorrhage and interstitial edema reduce pulmonary parenchymal elasticity. Therefore, both lung and chest wall compliance decrease. PCO 2 , A -a

gradient, and shunt fractions would probably be elevated, and ventricular contractions would probably be decreased.

7–8. The answers are 7-C [Chapter 5, II B 2] and 8-B [Chapter 5, II C 2–3 ]. The patient developing a pleural effusion in the setting of an underlying pneumonia requires thoracentesis for diagnosis. The character of the fluid described is consistent with that present in an empyema. Initial treatment of an empyema should involve closed chest tube drainage. Thoracotomy and decortication or rib resection may be required when the empyema is not adequately drained by the chest tube or is otherwise not amenable to closed drainage. Video-assisted thorascopic surgery pleurodesis is not standard treatment for an empyema.

9. The answer is D [Chapter 5, IV B 5]. The patient has a solitary pulmonary nodule. He is older than age 40, and the characteristics do not favor a benign lesion, such as concentric calcification. In addition, the lesion was not present on the chest radiograph 5 years earlier. Diagnosis is mandatory for determining whether the lesion is malignant. This can be done by needle biopsy or thoracoscopic biopsy.

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10. The answer is C [Chapter 4, II B ]. This patient is presenting with a diaphragmatic disruption, as evidenced by the identification of the stomach in the chest. Treatment involves standard resuscitation principles, (Airway, Breathing, Circulation), placement of a nasogastric tube to prevent acute gastric dilitation (which can produce severe, life -threatening respiratory distress), and urgent transabdominal repair of the diaphragmatic defect. If diagnosis is delayed by 7–10 days, transthoracic repair is preferred to

facilitate the freeing of any adhesions to the lung.

11. The answer is E [Chapter 6, II A ]. The most common forms of congenital heart disease are, in decreasing order: ventral septal defect, transposition of the great vessels, tetralogy of Fallot, hypoplastic left heart syndrome, atrial septal defect, and patent ductus arteriosus.

12. The answer is E [Chapter 5, IV B ]. Isolated lung nodules less than 1.0 cm are known as coin lesions. Workup should include a detailed history, noting any use of tobacco products or previous malignancy. Any prior chest radiographs should be obtained. A calcified lesion that has not enlarged over a 2-year period suggests a benign process. In this patient, observation with follow-up x-ray is indicated. Any change in the lesion is an indication for biopsy.

13. The answer is D [Chapter 5, V F ]. The appropriate treatment is surgical lobectomy. Observation with repeat chest x-ray is not warranted with a smoking history.

This patient is in clinical stage I, based on tumor size and nodal status. There is no clear benefit in biopsying the lesion. Chemotherapy and radiation may be indicated in certain stage IIIa lesions or in locally advanced disease.

14. The answer is C [Chapter 5, X C]. The most common posterior mediastinal mass is a neurogenic tumor. Seventy -five percent of neurogenic tumors occur in children under 4 years of age. Childhood tumors are more likely to be malignant. Lymphoma, thymoma, and germ cell tumors are commonly located in the anterior mediastimun. Middle mediastinal lesions include bronchogenic and pericardial cysts. Metastatic adenocarcinoma may involve the pleural surfaces; however, lesions are often small and multiple.

15. The answer is D [Chapter 6, I B ]. Angina, syncope, and dyspnea are the classic symptoms of aortic stenosis. Physical examination generally reveals a systolic ejection murmur in the second right intercostal space. An electrocardiogram and serial cardiac enzymes should be obtained to rule out cardiac ischemia. The murmur of aortic insufficiency is diastolic with a clinical picture of heart failure.

16. The answer is D [Chapter 6, I E ]. Risk factors for coronary artery disease are the same as those for vascular disease in general––smoking, diabetes, obesity, hypertension, and hypercholesterolemia. While renal failure is often associated with coronary artery disease, this is because of the frequent association with other risk factors, such as hypertension and diabetes.

17. The answer is A [Chapter 6, I E ]. This patient has severe triple -vessel coronary disease. Studies have shown a significant survival advantage for patients in this category who are treated with surgical revascularization, rather than with medical management or angioplasty. Additional benefit may be realized in patients with compromised ventricular function.

18. The answer is A [Chapter 6, I B ]. This patient has aortic stenosis. Symptoms usually begin when the valve area is less than 1 cm2 .

19. The answer is B [Chapter 6, II D]. Echocardiogram searching for thrombus or septal defect should be obtained in a younger patient who suffers from a cerebral vascular accident. A second interspace murmur and fixed splitting of the second heart sound are classic findings in atrial septal defect. Anticoagulation for 4–6 weeks with elective repair of the atrial septal defect is the indicated treatment.

Tobacco abuse

Diabetes mellitus

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Hyperlipidemia

Family history of atherosclerosis

Hypertension

II Lower Extremity Occlusive Disease

Lower extremity occlusive disease includes occlusive disease of the femoral, popliteal, and tibial arteries (Fig. 7-1).

A Pathology

The most common cause of lower extremity disease is atherosclerosis, although other less common conditions can also cause occlusive disease.

The SFA is the artery most frequently involved. Disease usually occurs at the adductor muscle hiatus (Hunter's canal), where the SFA passes through the adductor muscle group to form the popliteal artery. When focal stenoses become critical, the entire SFA occludes; the profunda (deep) femoral artery provides collateral blood flow to maintain flow to the popliteal artery distally.