Gray's Anatomy – Thorax Exam
Questions and Answers
1 A 2-day-old newborn is diagnosed with transposition of the great arteries. Which
structure is primarily responsible for the division of the truncus arteriosus into the
great arteries? A. Septum secundum B. Septum primum C. Bulbar septum D.
Aorticopulmonary septum E. Endocardial cushions - answer- 1 D. The
aorticopulmonary septum functions to divide the truncus arteriosus and bulbus cordis
into the aorta and pulmonary trunk. The septum secundum forms an incomplete
separation between the two atria. The septum primum divides the atrium into right
and left halves. The bulbar septum is derived from the bulbus cordis and will give
rise to the interventricular septum inferior to the aorticopulmonary septum, eventually
fusing with it. The endocardial cushions play a role in the division of the AV canal
into right and left halves, by causing the AV cushions to approach each other. GAS
203; N 209; McM 185, 191
2 A 32-year-old woman in her third trimester of pregnancy is undergoing a routine
ultrasound examination. The examination of the fetus reveals enlarged and
echogenic lungs, an inverted diaphragm, and fetal ascites. Which condition is best
characterized by these signs? A. Laryngeal atresia B. Tracheal atresia C.
Polyhydramnios D. Lung hypoplasia E. Oligohydramnios - answer- 2 A. Laryngeal
atresia (congenital high airway obstruction syndrome) is a rare obstruction of the
upper fetal airway. Distal to the site of the atresia, the airways dilate, lungs enlarge
and become echogenic, the diaphragm flattens or inverts, and fetal ascites and/or
hydrops develop. Tracheal atresia is a rare obstruction of the trachea, commonly
found with a tracheoesophageal fistula, probably resulting from the unequal division
of foregut into esophagus and trachea. Polyhydramnios is an excess of amniotic
fluid, often associated with esophageal atresia or tracheoesophageal fistula. Lung
hypoplasia is reduced lung volume, often seen in infants with a congenital
diaphragmatic hernia. Oligohydramnios, or a decrease in amniotic fluid, is associated
with stunted lung development and pulmonary hypoplasia. GAS 172-178; N 230;
McM 200, 201, 204
3 A 2-year-old child is seen in the pediatric cardiology unit for a congenital heart
condition. Which of the following conditions occurs most often? A. Membranous
ventricular septal defect (VSD) B. Tetralogy of Fallot C. Muscular VSD D. Ostium
secundum defect E. Ostium primum defect - answer- 3 A. VSDs account for 25% of
congenital heart defects. The most common of these are defects in the membranous
portion of the interventricular septum (membranous VSDs). GAS 203; N 209; McM
185, 191
4 A 2-day-old infant is diagnosed with transposition of the great arteries. If this
condition were to be left untreated for more than 4 months, it would be fatal. Which
of the following structures must remain patent so that the infant can survive until
surgical correction of the malformation? A. Ductus arteriosus B. Umbilical arteries C.
Umbilical vein D. Coarctation of the aorta E. Pulmonary artery stenosis - answer- 4
A. In a case of transposition of the great arteries, oxygenated blood travels from the
,left ventricle into the pulmonary trunk, where it will eventually reach the lungs. In
contrast, the aorta would be carrying deoxygenated blood into the systemic
circulation. A PDA acts as a shunt between the aorta and pulmonary trunk, allowing
oxygenated and deoxygenated blood to mix and therefore allowing some
oxygenated blood to reach the tissues. None of the other answer choices would be
correct for this problem; with these structures remaining patent, the body would still
not receive sufficient oxygenated blood for survival to be possible. GAS 203; N 226;
McM 195
5 A 2-day-old newborn female is diagnosed with pulmonary artery stenosis,
overriding of the aorta, VSD, and hypertrophy of the right ventricle. Which condition
is best characterized by these signs? A. Tetralogy of Fallot B. Atrial septal defect C.
Transposition of the great vessels D. Pulmonary atresia E. VSD - answer- 5 A.
Tetralogy of Fallot is characterized by four cardiac defects: pulmonary stenosis,
VSD, overriding aorta, and these in turn lead to right ventricular hypertrophy. An
ASD is characterized by the communication between the two atria. In a case of
transposition of the great vessels, the aorta arises from the right ventricle and the
pulmonary trunk arises from the left ventricle. GAS 203; N 221; McM 188, 189
6 A 2-day-old newborn female is diagnosed with pulmonary artery stenosis,
overriding of the aorta, VSD, and hypertrophy of the right ventricle. Which of the
following embryologic mechanisms is most likely responsible for the development of
this cluster of anomalies? A. Superior malalignment of the subpulmonary
infundibulum B. Defect in the aorticopulmonary septum C. Endocardial cushion
defect D. Total anomalous pulmonary venous connections E. Atrioventricular canal
malformation - answer- 6 A. Superior malalignment of the subpulmonary
infundibulum causes stenosis of the pulmonary trunk. This leads to the four
symptoms mentioned and is known as tetralogy of Fallot. A defect in formation of the
aorticopulmonary septum is characteristic of transposition of the great arteries. An
endocardial cushion defect is associated with membranous VSDs. GAS 192-193,
203; N 221; McM 188, 189
7 A 5-year-old boy is admitted to the hospital with severe dyspnea. During physical
examination, a loud systolic murmur and a wide, fixed, split S2 sound is noted. What
is the most likely diagnosis? A. VSD B. Atrial septal defect C. Tetralogy of Fallot D.
Transposition of the great arteries E. Aortic stenosis - answer- 7 B. The murmur at
S2 localizes the defect at an atrioventricular valve. An ASD causes a diastolic
murmur in the tricuspid valve, whereas a VSD would cause a pansystolic murmur.
Transposition of the great arteries and aortic stenosis will cause a murmur at S1, and
tetralogy of Fallot does not cause a murmur at S1 or S2. GAS 203; N 217, 218; McM
189
8 A 3-month-old infant is diagnosed with Down syndrome (trisomy 21). A routine
cardiovascular examination reveals that the infant suffers from arrhythmias. What
other cardiac conditions are most likely to occur with Down syndrome? A. Tetralogy
of Fallot B. Transposition of the great arteries C. Atrial septal and VSDs D. Truncus
arteriosus E. Coarctation of the aorta - answer- 8 C. Down syndrome (more properly
called "trisomy 21") is associated with cardiovascular abnormalities such as
arrhythmias and atrial and VSDs. It is also characterized by mental retardation,
brachycephaly, flat nasal bridge, upward slant of the palpebral fissure, protruding
,tongue, simian crease, and clinodactyly of the fifth digit. GAS 203; N 217, 218; McM
188
9 A 3-month-old infant is diagnosed with a deletion at the 22q11 chromosome. A
routine cardiovascular examination reveals severe congenital cardiac malformation.
Which of the following malformations will most likely be associated with 22q11
syndrome? A. Tetralogy of Fallot and truncus arteriosus B. Transposition of the great
arteries C. Atrial septal and VSDs D. Coarctation of the aorta E. Aortic atresia -
answer- 9 A. Tetralogy of Fallot and truncus arteriosus are associated with DiGeorge
syndrome (22q11). Transposition of the great arteries is associated with maternal
diabetes. ASDs and VSDs are present in individuals with Down syndrome.
Coarctation of the aorta is related to Turner syndrome. Marfan syndrome is present
in individuals with aortic atresia. GAS 203; N 211; McM 188
10 A 28-year-old woman in her third trimester of pregnancy with a complaint of
dizziness for several days is admitted to the hospital. Physical examination reveals
that she has diabetes mellitus. Which of the following cardiac malformations is most
likely to affect the fetus when the mother has this disease? A. Tetralogy of Fallot B.
Transposition of the great arteries C. Atrial septal and VSDs D. Truncus arteriosus E.
Coarctation of the aorta - answer- 10 B. Transposition of the great arteries is
associated with maternal diabetes. Tetralogy of Fallot and truncus arteriosus are
associated with DiGeorge syndrome (22q11). ASDs and VSDs are present in
individuals with Down syndrome. Coarctation of the aorta is related to Turner
syndrome. Marfan syndrome is present in individuals with aortic atresia. GAS 197,
203; N 211; McM 185, 191
11 During cardiac catheterization of a 6-year-old child, the radiologist notes that the
contrast medium released into the arch of the aorta is visible immediately in the left
pulmonary artery. What is the most likely explanation for this finding? A. Atrial septal
defect B. Mitral stenosis C. Patent ductus arteriosus D. Patent ductus venosus E.
VSD - answer- 11 C. The ductus arteriosus is an embryologic structure that acts as a
communication between the pulmonary trunk and the aorta. If it remains patent, the
injected contrast medium would flow from the aorta through this communication and
into the pulmonary artery. An ASD is a communication between the atria. Mitral
stenosis is a narrowing of the AV valve between the left atrium and left ventricle. The
ductus venosus transports blood from the left umbilical vein to the inferior vena cava,
bypassing the liver. A VSD is a communication between the ventricles. GAS 203; N
211; McM 195
12 A 3-year-old male patient presents with a clinically significant atrial septal defect
(ASD). The ASD usually results from incomplete closure of which of the following
structures? A. Foramen ovale B. Ligamentum arteriosum C. Ductus arteriosus D.
Sinus venarum E. Coronary sinus - answer- 12 A. An ASD is a communication
between the right and left atria. In the formation of the partition between the two
atria, the opening in the foramen secundum, also known as the foramen ovale,
typically closes at birth. If it remains patent, an ASD will result. The rest of the
structures are not associated with ASDs. GAS 203; N 217-218; McM 187
13 A premature infant has progressive difficulty in breathing and is diagnosed with
respiratory distress syndrome. Which cells are deficient in synthesizing surfactant in
, this syndrome? A. Alveolar capillary endothelial B. Bronchial mucous C. Bronchial
respiratory epithelium D. Type I alveolar E. Type II alveolar - answer- 13 E. Type II
alveolar cells are the only cells that produce surfactant. GAS 167-174; N 193; McM
200
14 A newborn baby is diagnosed with eventration of the diaphragm. In this condition,
half of the diaphragm ascends into the thorax during inspiration, while the other half
contracts normally. What is the cause of this condition? A. Absence of a
pleuropericardial fold B. Absence of musculature in one half of the diaphragm C.
Failure of migration of diaphragm D. Failure of the septum transversum to develop E.
Absence of a pleuroperitoneal fold - answer- 14 B. An absence of musculature in
one half of the diaphragm causes it to protrude into the thoracic cavity forming a
pouch into which the abdominal viscera protrude. Pleuropericardial folds are
responsible for separating the pericardial cavity from the pleural cavity. Typically, the
diaphragm migrates to its position with the fibrous pericardium. The septum
transversum is the primordial central tendon of the diaphragm that separates the
heart from the liver. The pleuroperitoneal folds form the pleuroperitoneal membranes
that separate the pleural cavity from the peritoneal cavity. Absence of any of these
would not have anything to do with eventration of the diaphragm. GAS 262; N 191;
McM 184
15 A 35-year-old man is admitted to the emergency department because of a severe
nosebleed (epistaxis) and a headache that had become worse during the weekend.
On physical examination, his upper body appears much better developed than his
lower body, a loud midsystolic murmur is present on his anterior chest wall and back,
his lower extremities are cold, and femoral pulses are absent. Which of the following
embryologic structure(s) has been most likely affected to produce such symptoms?
A. Bulbus cordis B. Ductus arteriosus C. Third, fourth, and sixth pharyngeal arches
D. Right and left horns of sinus venosus E. Right cardinal vein - answer- 15 C. The
anomalies present in this individual are all caused by a coarctation of the aorta. The
portion of the aortic arch that is constricted arises from the third, fourth, and sixth
pharyngeal arches. The bulbus cordis becomes part of the ventricular system. The
ductus arteriosus becomes the ligamentum arteriosum. GAS 217; N 209; McM 195
16 After a 2-day-old newborn male swallows milk he becomes cyanotic. After 3 days,
he develops aspiration pneumonia. A tracheoesophageal fistula is suspected. Failure
of development has occurred most specifically in which of the following structures?
A. Esophagus B. Trachea C. Tongue D. Tracheoesophageal septum E. Pharynx -
answer- 16 D. The tracheoesophageal septum is a primordial structure that
separates the trachea from the esophagus. If this structure fails to develop, a
tracheoesophageal fistula will result, in which event the two structures will not
separate completely. When the infant attempts to swallow milk, it spills into the
esophageal pouch and is regurgitated. The child becomes cyanotic because an
insufficient amount of oxygen is reaching the lungs as a result of the malformed
trachea. GAS 218; N 230; McM 197
17 After a 2-day-old newborn male swallows milk he becomes cyanotic. After 3 days
he develops pneumonia. A tracheoesophageal fistula is suspected. Which of the
following conditions is most likely to be associated with a tracheoesophageal fistula?
A. Oligohydramnios B. Rubella C. Polyhydramnios D. Thalidomide exposure E.
Questions and Answers
1 A 2-day-old newborn is diagnosed with transposition of the great arteries. Which
structure is primarily responsible for the division of the truncus arteriosus into the
great arteries? A. Septum secundum B. Septum primum C. Bulbar septum D.
Aorticopulmonary septum E. Endocardial cushions - answer- 1 D. The
aorticopulmonary septum functions to divide the truncus arteriosus and bulbus cordis
into the aorta and pulmonary trunk. The septum secundum forms an incomplete
separation between the two atria. The septum primum divides the atrium into right
and left halves. The bulbar septum is derived from the bulbus cordis and will give
rise to the interventricular septum inferior to the aorticopulmonary septum, eventually
fusing with it. The endocardial cushions play a role in the division of the AV canal
into right and left halves, by causing the AV cushions to approach each other. GAS
203; N 209; McM 185, 191
2 A 32-year-old woman in her third trimester of pregnancy is undergoing a routine
ultrasound examination. The examination of the fetus reveals enlarged and
echogenic lungs, an inverted diaphragm, and fetal ascites. Which condition is best
characterized by these signs? A. Laryngeal atresia B. Tracheal atresia C.
Polyhydramnios D. Lung hypoplasia E. Oligohydramnios - answer- 2 A. Laryngeal
atresia (congenital high airway obstruction syndrome) is a rare obstruction of the
upper fetal airway. Distal to the site of the atresia, the airways dilate, lungs enlarge
and become echogenic, the diaphragm flattens or inverts, and fetal ascites and/or
hydrops develop. Tracheal atresia is a rare obstruction of the trachea, commonly
found with a tracheoesophageal fistula, probably resulting from the unequal division
of foregut into esophagus and trachea. Polyhydramnios is an excess of amniotic
fluid, often associated with esophageal atresia or tracheoesophageal fistula. Lung
hypoplasia is reduced lung volume, often seen in infants with a congenital
diaphragmatic hernia. Oligohydramnios, or a decrease in amniotic fluid, is associated
with stunted lung development and pulmonary hypoplasia. GAS 172-178; N 230;
McM 200, 201, 204
3 A 2-year-old child is seen in the pediatric cardiology unit for a congenital heart
condition. Which of the following conditions occurs most often? A. Membranous
ventricular septal defect (VSD) B. Tetralogy of Fallot C. Muscular VSD D. Ostium
secundum defect E. Ostium primum defect - answer- 3 A. VSDs account for 25% of
congenital heart defects. The most common of these are defects in the membranous
portion of the interventricular septum (membranous VSDs). GAS 203; N 209; McM
185, 191
4 A 2-day-old infant is diagnosed with transposition of the great arteries. If this
condition were to be left untreated for more than 4 months, it would be fatal. Which
of the following structures must remain patent so that the infant can survive until
surgical correction of the malformation? A. Ductus arteriosus B. Umbilical arteries C.
Umbilical vein D. Coarctation of the aorta E. Pulmonary artery stenosis - answer- 4
A. In a case of transposition of the great arteries, oxygenated blood travels from the
,left ventricle into the pulmonary trunk, where it will eventually reach the lungs. In
contrast, the aorta would be carrying deoxygenated blood into the systemic
circulation. A PDA acts as a shunt between the aorta and pulmonary trunk, allowing
oxygenated and deoxygenated blood to mix and therefore allowing some
oxygenated blood to reach the tissues. None of the other answer choices would be
correct for this problem; with these structures remaining patent, the body would still
not receive sufficient oxygenated blood for survival to be possible. GAS 203; N 226;
McM 195
5 A 2-day-old newborn female is diagnosed with pulmonary artery stenosis,
overriding of the aorta, VSD, and hypertrophy of the right ventricle. Which condition
is best characterized by these signs? A. Tetralogy of Fallot B. Atrial septal defect C.
Transposition of the great vessels D. Pulmonary atresia E. VSD - answer- 5 A.
Tetralogy of Fallot is characterized by four cardiac defects: pulmonary stenosis,
VSD, overriding aorta, and these in turn lead to right ventricular hypertrophy. An
ASD is characterized by the communication between the two atria. In a case of
transposition of the great vessels, the aorta arises from the right ventricle and the
pulmonary trunk arises from the left ventricle. GAS 203; N 221; McM 188, 189
6 A 2-day-old newborn female is diagnosed with pulmonary artery stenosis,
overriding of the aorta, VSD, and hypertrophy of the right ventricle. Which of the
following embryologic mechanisms is most likely responsible for the development of
this cluster of anomalies? A. Superior malalignment of the subpulmonary
infundibulum B. Defect in the aorticopulmonary septum C. Endocardial cushion
defect D. Total anomalous pulmonary venous connections E. Atrioventricular canal
malformation - answer- 6 A. Superior malalignment of the subpulmonary
infundibulum causes stenosis of the pulmonary trunk. This leads to the four
symptoms mentioned and is known as tetralogy of Fallot. A defect in formation of the
aorticopulmonary septum is characteristic of transposition of the great arteries. An
endocardial cushion defect is associated with membranous VSDs. GAS 192-193,
203; N 221; McM 188, 189
7 A 5-year-old boy is admitted to the hospital with severe dyspnea. During physical
examination, a loud systolic murmur and a wide, fixed, split S2 sound is noted. What
is the most likely diagnosis? A. VSD B. Atrial septal defect C. Tetralogy of Fallot D.
Transposition of the great arteries E. Aortic stenosis - answer- 7 B. The murmur at
S2 localizes the defect at an atrioventricular valve. An ASD causes a diastolic
murmur in the tricuspid valve, whereas a VSD would cause a pansystolic murmur.
Transposition of the great arteries and aortic stenosis will cause a murmur at S1, and
tetralogy of Fallot does not cause a murmur at S1 or S2. GAS 203; N 217, 218; McM
189
8 A 3-month-old infant is diagnosed with Down syndrome (trisomy 21). A routine
cardiovascular examination reveals that the infant suffers from arrhythmias. What
other cardiac conditions are most likely to occur with Down syndrome? A. Tetralogy
of Fallot B. Transposition of the great arteries C. Atrial septal and VSDs D. Truncus
arteriosus E. Coarctation of the aorta - answer- 8 C. Down syndrome (more properly
called "trisomy 21") is associated with cardiovascular abnormalities such as
arrhythmias and atrial and VSDs. It is also characterized by mental retardation,
brachycephaly, flat nasal bridge, upward slant of the palpebral fissure, protruding
,tongue, simian crease, and clinodactyly of the fifth digit. GAS 203; N 217, 218; McM
188
9 A 3-month-old infant is diagnosed with a deletion at the 22q11 chromosome. A
routine cardiovascular examination reveals severe congenital cardiac malformation.
Which of the following malformations will most likely be associated with 22q11
syndrome? A. Tetralogy of Fallot and truncus arteriosus B. Transposition of the great
arteries C. Atrial septal and VSDs D. Coarctation of the aorta E. Aortic atresia -
answer- 9 A. Tetralogy of Fallot and truncus arteriosus are associated with DiGeorge
syndrome (22q11). Transposition of the great arteries is associated with maternal
diabetes. ASDs and VSDs are present in individuals with Down syndrome.
Coarctation of the aorta is related to Turner syndrome. Marfan syndrome is present
in individuals with aortic atresia. GAS 203; N 211; McM 188
10 A 28-year-old woman in her third trimester of pregnancy with a complaint of
dizziness for several days is admitted to the hospital. Physical examination reveals
that she has diabetes mellitus. Which of the following cardiac malformations is most
likely to affect the fetus when the mother has this disease? A. Tetralogy of Fallot B.
Transposition of the great arteries C. Atrial septal and VSDs D. Truncus arteriosus E.
Coarctation of the aorta - answer- 10 B. Transposition of the great arteries is
associated with maternal diabetes. Tetralogy of Fallot and truncus arteriosus are
associated with DiGeorge syndrome (22q11). ASDs and VSDs are present in
individuals with Down syndrome. Coarctation of the aorta is related to Turner
syndrome. Marfan syndrome is present in individuals with aortic atresia. GAS 197,
203; N 211; McM 185, 191
11 During cardiac catheterization of a 6-year-old child, the radiologist notes that the
contrast medium released into the arch of the aorta is visible immediately in the left
pulmonary artery. What is the most likely explanation for this finding? A. Atrial septal
defect B. Mitral stenosis C. Patent ductus arteriosus D. Patent ductus venosus E.
VSD - answer- 11 C. The ductus arteriosus is an embryologic structure that acts as a
communication between the pulmonary trunk and the aorta. If it remains patent, the
injected contrast medium would flow from the aorta through this communication and
into the pulmonary artery. An ASD is a communication between the atria. Mitral
stenosis is a narrowing of the AV valve between the left atrium and left ventricle. The
ductus venosus transports blood from the left umbilical vein to the inferior vena cava,
bypassing the liver. A VSD is a communication between the ventricles. GAS 203; N
211; McM 195
12 A 3-year-old male patient presents with a clinically significant atrial septal defect
(ASD). The ASD usually results from incomplete closure of which of the following
structures? A. Foramen ovale B. Ligamentum arteriosum C. Ductus arteriosus D.
Sinus venarum E. Coronary sinus - answer- 12 A. An ASD is a communication
between the right and left atria. In the formation of the partition between the two
atria, the opening in the foramen secundum, also known as the foramen ovale,
typically closes at birth. If it remains patent, an ASD will result. The rest of the
structures are not associated with ASDs. GAS 203; N 217-218; McM 187
13 A premature infant has progressive difficulty in breathing and is diagnosed with
respiratory distress syndrome. Which cells are deficient in synthesizing surfactant in
, this syndrome? A. Alveolar capillary endothelial B. Bronchial mucous C. Bronchial
respiratory epithelium D. Type I alveolar E. Type II alveolar - answer- 13 E. Type II
alveolar cells are the only cells that produce surfactant. GAS 167-174; N 193; McM
200
14 A newborn baby is diagnosed with eventration of the diaphragm. In this condition,
half of the diaphragm ascends into the thorax during inspiration, while the other half
contracts normally. What is the cause of this condition? A. Absence of a
pleuropericardial fold B. Absence of musculature in one half of the diaphragm C.
Failure of migration of diaphragm D. Failure of the septum transversum to develop E.
Absence of a pleuroperitoneal fold - answer- 14 B. An absence of musculature in
one half of the diaphragm causes it to protrude into the thoracic cavity forming a
pouch into which the abdominal viscera protrude. Pleuropericardial folds are
responsible for separating the pericardial cavity from the pleural cavity. Typically, the
diaphragm migrates to its position with the fibrous pericardium. The septum
transversum is the primordial central tendon of the diaphragm that separates the
heart from the liver. The pleuroperitoneal folds form the pleuroperitoneal membranes
that separate the pleural cavity from the peritoneal cavity. Absence of any of these
would not have anything to do with eventration of the diaphragm. GAS 262; N 191;
McM 184
15 A 35-year-old man is admitted to the emergency department because of a severe
nosebleed (epistaxis) and a headache that had become worse during the weekend.
On physical examination, his upper body appears much better developed than his
lower body, a loud midsystolic murmur is present on his anterior chest wall and back,
his lower extremities are cold, and femoral pulses are absent. Which of the following
embryologic structure(s) has been most likely affected to produce such symptoms?
A. Bulbus cordis B. Ductus arteriosus C. Third, fourth, and sixth pharyngeal arches
D. Right and left horns of sinus venosus E. Right cardinal vein - answer- 15 C. The
anomalies present in this individual are all caused by a coarctation of the aorta. The
portion of the aortic arch that is constricted arises from the third, fourth, and sixth
pharyngeal arches. The bulbus cordis becomes part of the ventricular system. The
ductus arteriosus becomes the ligamentum arteriosum. GAS 217; N 209; McM 195
16 After a 2-day-old newborn male swallows milk he becomes cyanotic. After 3 days,
he develops aspiration pneumonia. A tracheoesophageal fistula is suspected. Failure
of development has occurred most specifically in which of the following structures?
A. Esophagus B. Trachea C. Tongue D. Tracheoesophageal septum E. Pharynx -
answer- 16 D. The tracheoesophageal septum is a primordial structure that
separates the trachea from the esophagus. If this structure fails to develop, a
tracheoesophageal fistula will result, in which event the two structures will not
separate completely. When the infant attempts to swallow milk, it spills into the
esophageal pouch and is regurgitated. The child becomes cyanotic because an
insufficient amount of oxygen is reaching the lungs as a result of the malformed
trachea. GAS 218; N 230; McM 197
17 After a 2-day-old newborn male swallows milk he becomes cyanotic. After 3 days
he develops pneumonia. A tracheoesophageal fistula is suspected. Which of the
following conditions is most likely to be associated with a tracheoesophageal fistula?
A. Oligohydramnios B. Rubella C. Polyhydramnios D. Thalidomide exposure E.
