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Thoracic Surgery: Answers
299
Descriptors
Definitions
T2
Tumor > 3 but ≤ 7 cm or tumor with any of the following: Invades visceral
pleura, involves main bronchus ≥ 2 cm distal to the carina,
atelectasis/obstructive pneumonia extending to hilum but not involving the
entire lung
T2a
Tumor > 3 but ≤ 5 cm
T2b
Tumor > 5 but ≤ 7 cm
T3
Tumor > 7 cm;
or directly invading chest wall, diaphragm, phrenic nerve, mediastinal pleura,
or parietal pericardium;
or tumor in the main bronchus < 2 cm distal to the carina;
or atelectasis/obstructive pneumonitis of entire lung;
or separate tumor nodules in the same lobe
T4
Tumor of any size with invasion of heart, great vessels, trachea, recurrent
laryngeal nerve, esophagus, vertebral body, or carina;
or separate tumor nodules in a different ipsilateral lobe
N
Regional lymph nodes
N0
No regional node metastasis
N1
Metastasis in ipsilateral peribronchial and/or perihilar lymph nodes and
intrapulmonary nodes, including involvement by direct extension
N2
Metastasis in ipsilateral mediastinal and/or subcarinal lymph nodes
N3
Metastasis in contralateral mediastinal, contralateral hilar, ipsilateral or
contralateral scalene, or supraclavicular lymph nodes
M
Distant metastasis
M0
No distant metastasis
M1a
Separate tumor nodules in a contralateral lobe;
or tumor with pleural nodules or malignant pleural dissemination
‖
M1b
Distant metastasis
Special
situations
TX, NX, MX
T, N, or M status not able to be assessed
Tis
Focus of in situ cancer
T1
Superficial spreading tumor of any size but confined to the wall of the trachea
or mainstem bronchus
References
Rami-Porta R, Crowley JJ, Goldstraw P. The revised TNM staging system for lung cancer.
Ann Thorac Cardiovasc Surg. 2009;15:4-9.
Tanoue LT, Detterbeck FC. New TNM classification for non-small-cell lung cancer. Expert
Rev Anticancer Ther. 2009;9:413-23.
Chapter IV
Paediatric Cardiothoracic Surgery
4.1 Answer: C
The bicuspid aortic valve (BAV) is the most frequent congenital cardiac anomaly in
adults, with prevalence in the general population ranging from 0.9 to 2.0%. Basso et al. in a
recent echocardiographic survey on primary school children (aged 5 to 10 years) reported a
BAV prevalence of 0.5%. The prevalence of BAV was significantly higher in males (0.75%)
compared to females (0.24%).
The embryogenesis of the aortic valve is not clear. The fundamental element in the
formation of BAV appears to be the fusion of two adjoining leaflets at the beginning of the
valvulogenesis. One theory suggests that the embryological pathogenesis of BAV could be
associated with an alteration in the derivatives of the neural crest. Several cardiac and non-
cardiac structures (such as left ventricular outflow tract, aortic valve and arch, and other
organs in the head and neck) that arise from the neural crest can be altered in the presence of
BAV. Another theory links BAV to genetic defects, with culprit genes being those encoding
for extracellular matrix support proteins such as fibrillin-1. This theory could also provide a
plausible explanation for association of BAV with other cardiovascular anomalies (i.e.,
coarctation of the aorta, patent ductus arteriosus, hypoplastic left ventricular outflow tract,
etc.) and its often observed familial occurrence (particularly in males), suggesting an
autosomal dominant inheritance with reduced penetrance. Majority of adult patients
undergoing aortic valve replacement for BAV have fusion of the right and left coronary
cusps.
Although a BAV may remain without clinical sequelae for a lifetime, it can have severe
complications, sometimes necessitating surgery. BAV is susceptible to fibrosis and
calcification of cusps, and has a greater risk of developing endocarditis. BAV is also
associated with valve stenosis and/or regurgiation, as well as aortic complications such as
dilation and dissection. Histologically, the aorta of patients with a BAV may show cystic
medial necrosis, loss of elastic fibres, increased apoptosis, and altered smooth muscle cell
alignment.
Aortic stenosis is the most common complication affecting approximately 50% of
patients with BAV, particularly older individuals. Compared to the normal tricuspid valve
there is accelerated fibrosis and superimposed cusp calcification with independent, modifiable
risk factors, such as poor lipid profile and cigarette smoking, favouring BAV degeneration. A
Shahzad G. Raja
302
stenotic BAV eventually requires surgical replacement once valve obstruction becomes
severe and symptoms unendurable.
Compared to isolated stenosis, isolated aortic regurgitation usually affects individuals at a
younger age. The causes of insufficiency are more difficult to explain than those regarding
stenosis. Valvular regurgitation may be isolated, being due to prolapse of the greater cusp, but
it can be secondary to dilation of aortic root and/or the sino-tubular junction, to aortic
coarctation or to endocarditis. Finally, younger subjects with BAV are at an increased risk of
endocarditis in the presence of aortic regurgitation. The need for surgery in the presence of
significant insufficiency is dictated by the appearance of symptoms or when the volume
overloaded left ventricle is excessively enlarged.
Approximately 30% of subjects with BAV may suffer endocarditis. It is more common in
children and young adults, particularly males, than in elderly patients. Staphylococcus spp.
and Streptococcus viridians are the most frequent microorganisms associated with
endocarditis in BAV patients, although several other causative factors have been described.
Dilation of aortic root, sino-tubular junction and ascending aorta out of proportion to
valvular lesions, is a relatively well-known phenomenon, suggesting a primitive disease of
both BAV and ascending aorta, probably due to abnormalities in connective, elastic, tissue.
Over 50% of subjects with a ‗normally functioning‘ BAV have a dilated aorta on
echocardiography, which is thought to be the basis for future aortic dissection. Aortic
dissection actually develops in 5% of subjects with BAV and, among young subjects who
develop aortic dissection BAV is nine times more common than in older patients. It seems
reasonable to say, however, that the probability of aortic dissection is higher in patients with
significant aortic dilation and, most importantly, in those with progressive, rapid increase in
aortic diameter during time (more than 1 mm every year).
References
Basso C, Boschello M, Perrone C, et al. An echocardiographic survey of primary school
children for bicuspid aortic valve. Am J Cardiol. 2004; 93:661-663.
Cripe L, Andelfinger G, Martin LJ, et al. Bicuspid aortic valve is heritable. J Am Coll
Cardiol. 2004; 44:138-143.
Yener N, Oktar GL, Erer D, et al. Bicuspid aortic valve. Ann Thorac Cardiovasc Surg. 2002;
8:264-267.
Fedak PWM, Verma S, David TE, et al. Clinical and pathophysiological implications of a
bicuspid aortic valve. Circulation. 2002;106:900-904.
Sabet HY, Edwards WD, Tazelaar HD, et al. Congenitally bicuspid aortic valves: a surgical
pathology study of 542 cases (1991 through 1996) and a literature review of 2,715
additional cases. Mayo Clin Proc. 1999;74:14-26.
4.2 Answer: A
Persistent left superior vena cava (PLSVC) is the most common congenital thoracic
venous abnormality with a prevalence of 0.3–0.5% in general population. The thoracic
embryonic venous system consists of two large veins (the superior cardinal veins) which
return blood from the top aspect of embryo, and the inferior cardinal vein, which returns
blood from the bottom aspect. Both pairs of veins join to form right and left common cardinal
veins before entering the embryological heart. The left common cardinal vein persists to form
coronary sinus and oblique vein of left atrium. During the 8
th
week of pregnancy, a
Paediatric Cardiothoracic Surgery: Answers
303
connection develops between right and left superior cardinal veins resulting in the innominate
(or brachiocephalic) vein. The cranial part of superior cardinal veins form the internal jugular
veins. The caudal part of right superior vein forms the normal right-sided superior vena cava,
while the portion of the left superior cardinal vein caudal to the innominate vein normally
degenerates to become "ligament of Marshall". If this normal regression of the left superior
cardinal vein fails to occur, a persistent left-sided vascular structure that drains into the
coronary sinus, results (the PLSVC). The innominate vein may or may not degenerate in these
cases resulting in anatomical variations.
The most frequent subtype of PLSVC is characterised by the presence of both left and
right SVCs. A bridging innominate vein may or may not be present. It is reported that a
PLSVC is associated with non-existence of the innominate vein in 65% cases. Infrequently,
the caudal right superior cardinal vein regresses resulting in an absent right SVC with
PLSVC. In this case, the left SVC drains all the blood from cranial aspect of the body.
Variations have also been reported in the drainage of left SVC. In 80–90% of individuals, the
persistent LSVC drains into the right atrium via the coronary sinus and is of no hemodynamic
consequence. In the remaining cases, it may drain in left atrium resulting in a right to left
sided shunt.
PLSVC is associated with a variety of congenital cardiac anomalies, such as atrial septal
defect, bicuspid aortic valve, coarctation of aorta, coronary sinus ostial atresia, and cor
triatriatum, in approximately 40% of patients. The presence of associated abnormalities is
more common with concomitant absence of right SVC. Anatomical and architectural
abnormalities of the sinus node and conduction tissues are also recognised associations of the
PLSVC.
It is usually asymptomatic and is detected incidentally when cardiovascular imaging is
performed for unrelated reasons or during surgery. It can however pose technical difficulties
and complicate catheter placement within the right side of heart when a left subclavian
approach is used for vascular access.
References
Goyal SK, Punnam SR, Verma G, et al. Persistent left superior vena cava: a case report and
review of literature. Cardiovasc Ultrasound. 2008;6:50.
Sarodia B, Stoller J. Persistent left superior vena cava: case report and literature review.
Respir Care. 2000;45:411-416.
Voci P, Luzi G, Agati L. Diagnosis of persistent left superior vena cava by multiplane
transesophageal echocardiography. Cardiologia. 1995;40:273-275.
Webb W, Gamsu G, Speckman JM, et al. Computed tomographic demonstration of
mediastinal venous anomalies. AJR Am J Roentgenol. 1982;139:157-161.
4.3 Answer: C
The ductus arteriosus is a normal and indispensable foetal structure
that becomes
abnormal if it fails to regress after the neonatal
period. During normal embryonic
cardiovascular development, the proximal segments
of the sixth pair of embryonic aortic
arches persist as the
proximal branch pulmonary arteries, and the distal segment of
the left
sixth arch persists as the ductus arteriosus, joining
the left pulmonary artery with the left
dorsal aorta.
Normally, the distal right sixth aortic arch degenerates and loses its connection
to
the dorsal aorta. This transformation is
complete by 8 weeks of foetal life.
Shahzad G. Raja
304
During foetal life although ≈ 65% of the cardiac output is from the right ventricle,
only
5% to 10% passes through the lungs. The major portion
of right ventricular output passes
through the ductus arteriosus
into the descending aorta. The foetal ductus arteriosus is an
important structure that is vital for normal foetal development, ensuring that right ventricular
output is diverted away from
the high-resistance pulmonary circulation. Premature stenosis
or
closure of the ductus arteriosus may cause right heart failure, resulting in foetal
hydrops.
Although the foetal ductus arteriosus and contiguous main pulmonary artery and
descending
aorta appear to have similar gross constitution however there are important
histological differences. The media of the ductus arteriosus is composed
of longitudinally and
spirally arranged layers of smooth muscle
fibers within loose, concentric layers of elastic
tissue contrary to the mainly circumferentially arranged layers of
elastic fibers within the
mediae of surrounding aorta and pulmonary artery. The
intima of the ductus arteriosus forms
intimal
cushions by being thickened and irregular,
with abundant mucoid material.
The ductus arteriosus remains patent during foetal period due to low foetal
oxygen
tension and cyclooxygenase-mediated products of arachidonic
acid metabolism (primarily
prostaglandin [PGE
2
] and prostacyclin
[PGI
2
]). Ductal prostanoid receptors interact with
locally produced and circulating PGE
2
and PGI
2
in
the foetus to cause vasodilation of the
ductus arteriosus. Production by the
placenta and decreased metabolism in the foetal lungs
results in high circulating PGE
2
and
PGI
2
levels in the foetus.
After birth, there is an abrupt increase in oxygen tension that inhibits
ductal smooth
muscle voltage-dependent potassium channels with an influx of calcium. At the same time
because of metabolism in the now functioning
lungs and elimination of the placental source
PGE
2
and PGI
2
levels fall. These changes lead to contraction of medial smooth
muscle fibers
in the ductus, which causes wall
thickening, lumen obliteration, and shortening of the ductus
arteriosus. In term neonates within
24 to 48 hours of birth functional complete closure usually
occurs. Infolding of the endothelium along with subintimal
disruption and proliferation
produces fibrosis and a permanent
seal within the next 2
to 3 weeks. The resulting remnant
fibrous band with no lumen persists as
the ligamentum arteriosum.
References
Schneider DJ, Moore JW. Patent ductus arteriosus. Circulation. 2006;114:1873-82.
Leonhardt A, Glaser A, Wegmann M, et al. Expression of prostanoid receptors in human
ductus arteriosus. Br J Pharmacol. 2003; 138: 655-659.
Gittenberger-De Groot AC, van Ertbruggen I, Moulaert AJ, et al. The ductus arteriosus in the
preterm infant: histologic and clinical observations. J Pediatr. 1980;96:88-93.
4.4 Answer: E
Currently there is a lack of complete understanding about the factors responsible for
persistent patency of the ductus
arteriosus beyond the first 24 to 48 hours of neonatal life.
There is a well-recognised increased incidence of patent ductus arteriosus (PDA) in pre-term
infants, and this is due to physiological factors
related to prematurity rather than inherent
abnormality of the
ductus. Other factors associated with increased incidence of PDA include
prenatal infection and genetic factors.
In children who were born at term,
the reported incidence of PDA is ≈ 1 in 2000 births.
This accounts for ≈ 5% to 10% of all congenital heart disease.
However, if children with
"silent" PDA (those discovered incidentally by echocardiography performed
for another
Paediatric Cardiothoracic Surgery: Answers
305
purpose) are included, the incidence has been estimated to be
as high as 1 in 500. The female
to male ratio is ≈ 2:1 in most
reports.
In term infants PDA most likely
results from a significant structural abnormality
compared to premature infants, in whom PDA generally is due
to developmental immaturity.
Several genetic syndromes, including
those with defined chromosomal aberrations (such as
trisomy
21 and 4p– syndrome), single-gene mutations (such as Carpenter‘s
syndrome and
Holt-Oram syndrome), and X-linked mutations (such
as incontinentia pigmenti) are associated
with an increased frequency of PDA. Despite majority of cases of PDA appearing to be
sporadic, many are believed to be due to multifactorial inheritance,
with the requirement of
genetic predisposition and an environmental
trigger that occurs at a vulnerable time. In some
patients occurrence of PDA may be inherited in an autosomal recessive
pattern with
incomplete penetrance. There is an ≈ 3% chance of a PDA in a subsequent
offspring in a
family already having
1 sibling with a PDA,.
The precise mechanisms of how these genetic abnormalities result
in persistent patency of
the ductus arteriosus are not clearly understood.
There is evidence to suggest that the
abnormalities in Char syndrome
(an inherited disorder with PDA, facial dimorphism, and
hand
anomalies) result from derangement of neural crest cell derivatives. Abnormal
fibronectin-dependent smooth
muscle cell migration is also reported as a cause of PDA.
A high incidence of
PDA is associated with rubella infection during the first trimester of
pregnancy, particularly
in the first 4 weeks. The histology of PDA from rubella infected
infants resembles that of a very immature ductus,
and there is an extensive subendothelial
elastic lamina that
is thought to prevent anatomic sealing. PDA is also associated with other
environmental factors,
such as foetal valproate syndrome, although the mechanism
remains to
be elucidated.
References
Schneider DJ, Moore JW. Patent ductus arteriosus. Circulation. 2006;114:1873-82.
Hoffman JIE, Kaplan S. The incidence of congenital heart disease. J Am Coll Cardiol.
2002;39:1890-1900.
Mani A, Meraji S, Houshyar R, et al. Finding genetic contributions to sporadic disease: a
recessive locus at 12q24 commonly contributes to patent ductus arteriosus. Proc Nat
Acad Sci U S A. 2002;99:15054-15059.
Satoda M, Zhao F, Diaz GA, et al. Mutations in TFAP2B cause Char syndrome, a familial
form of patent ductus arteriosus. Nat Genet. 2000;25:42-46.
Satoda M, Pierpont ME, Diaz GA, et al. Char syndrome, an inherited disorder with patent
ductus arteriosus, maps to chromosome 6p12-p21. Circulation. 1999;99:3036-3042.
Gittenberger-de Groot AC, Moulaert AJ, Hitchcock JF. Histology of the persistent ductus
arteriosus in cases of congenital rubella. Circulation. 1980;62:183-186.
4.5 Answer: B
The magnitude of shunting, which depends
largely on the flow resistance of the ductus
arteriosus, determines the hemodynamic impact of patent ductus arterious (PDA) in an
otherwise normal cardiovascular
system. The
flow resistance is determined by the length, the
narrowest diameter, and the overall shape and configuration
of the ductus arteriosus. In
addition,
due to the dynamic and pulsatile nature of flow in the ductus, the impedance to
blood flow may be affected by the elasticity
of the ductus wall.
Shahzad G. Raja
306
In addition to ductal resistance, the magnitude of shunt flow also depends on the pressure
gradient between the aorta and the
pulmonary artery. This pressure gradient in turn depends
largely on pulmonary and
systemic vascular resistances and cardiac output. Larger ductus that
have less flow resistance are mainly affected by changes in pulmonary and systemic
resistances.
Left-to-right shunting through the ductus arteriosus produces pulmonary overcirculation
and left heart volume overload.
Patients with moderate or large
shunts experience increased
work of breathing subsequent to increased pulmonary flow from the ductal shunting resulting
in decreased lung compliance due to increased pulmonary fluid volume. Pulmonary oedema
although rare may occur in older patients with advanced congestive heart
failure.
Left atrial and left ventricular end-diastolic pressures increase secondary to increased
flow returning to the left heart. In response to volume overload the
left ventricle compensates
by increasing stroke volume and eventually
may hypertrophy to normalize wall stress.
Increased sympathetic activity and circulating
catecholamines also occur as neuroendocrine
adaptations. These cause increased contractility and heart
rate. Subendocardial ischaemia may
result due to a combination of decreased diastolic blood pressure in the aorta secondary to
diastolic "runoff" through the patent ductus, shorter diastolic time due to tachycardia,
increased intramyocardial
tension from left ventricular dilatation, and increased myocardial
oxygen demand.
Progressive
morphological changes in the pulmonary vasculature take place in response
to exposure of the pulmonary
artery system to high-pressure and increased flow as a result of
long-standing left-to-right shunting. Progressive increase in pulmonary
vascular resistance
results in response to these changes characterised by arteriolar medial hypertrophy, intimal
proliferation
and fibrosis, and eventual obliteration of pulmonary arterioles
and capillaries.
Eventually, reversal of ductal shunting occurs when pulmonary vascular resistance
approaches
and exceeds systemic vascular resistance. Although there is a lack of
understanding of the precise pathophysiological mechanisms
however it is suggested that
microvascular injury stimulates production of growth factors
and enzymes that result in
intimal proliferation and medial
hypertrophy. Obliteration of pulmonary arterioles is also
attributed to endothelial dysfunction and platelet activation.
References
Schneider DJ, Moore JW. Patent ductus arteriosus. Circulation. 2006;114:1873-82.
Celermajer DS, Cullen S, Deanfield JE. Impairment of endothelium-dependent pulmonary
artery relaxation in children with congenital heart disease and abnormal pulmonary
hemodynamics Circulation. 1993;87:440-446.
4.6 Answer: E
Disconnection of the tracheoesophageal fistula, closure of the tracheal defect and primary
anastomosis of the oesophagus constitute definitive management of oesophageal atresia and
tracheoesophageal fistula (TEF). Delayed primary repair should be attempted when there is a
"long gap" between the ends of the esophagus. Oesophageal replacement is very rarely
required. Most infants with oesophageal atresia and TEF should undergo primary repair soon
after birth. Only in the presence of extreme prematurity, respiratory failure either from
respiratory distress syndrome or aspiration pneumonia, complex congenital heart disease or
other conditions that preclude safe thoracotomy primary repair is delayed.
Paediatric Cardiothoracic Surgery: Answers
307
In order to minimize acid reflux, decompression of the subsequent oesophageal
anastomosis and facilitate feeding after surgery a gastrostomy tube is placed prior to
thoracotomy. The technique of repair involves a right thoracotomy with development of the
retropleural plane and exposure of the trachea, oesophagus and fistula. There is evidence that
the retropleural approach decreases the morbidity of an oesophageal anastomotic leak.
However, a transpleural approach can also be used. The proximal and distal pouches should
be mobilized and the fistulous tract divided with a small amount of tissue left on the trachea
so as to avoid tracheal narrowing. An end-to-end anastomosis should be performed under
minimal tension. Manoeuvres proposed to overcome a wide gap include tubularization of the
upper pouch after creating a flap, circular myotomy of the upper pouch or abandoning any
attempt at initial primary anastomosis awaiting delayed primary anastomosis 6-12 weeks
later.
References
Spitz L. Oesophageal atresia. Orphanet J Rare Dis. 2007;2:24.
Achildi O, Grewal H. Congenital anomalies of the esophagus. Otolaryngol Clin North Am.
2007;40:219-44.
4.7 Answer: D
Oesophageal atresia (OA) comprises a group of congenital anomalies characterised by
interruption of the continuity of the oesophagus with or without a persistent communication
with the trachea. In 86% of cases there is a distal tracheoesophageal fistula, in 7% there is no
fistulous connection, while in 4% there is a tracheooesophageal fistula without atresia. OA
occurs in 1 in 2500 live births. Excessive salivation requiring repeated suctioning with
inability to swallow saliva is a characteristic feature of infants with OA. The most common
presentation is a drooling neonate who develops respiratory distress due to pooling of saliva
in the proximal oesophageal pouch with overflow and aspiration. A chemical pneumonitis
secondary to spillage into the trachea through the distal tracheoesophageal fistula results from
free gastroesophageal reflux. In addition, gastric and intestinal distension occur due to
tracheal air entering the gastrointestinal tract through the fistula, which in turn elevates the
diaphragm and exacerbates the respiratory distress. 50% of cases have associated anomalies,
the majority involving one or more of the VACTERL association (vertebral, anorectal,
cardiac, tracheooesophageal, renal and limb defects).
Delaying the diagnosis until the infant presents with coughing and choking during the
first feed is no longer acceptable in modern paediatric practice.
Prenatally, the finding of a small or absent foetal stomach bubble on ultrasound scan
performed after the 18
th
week of gestation gives a clue to the diagnosis of OA. Overall the
sensitivity of ultrasonography alone is 42% but the positive predictive value is 56% in
combination with polyhydraminos. Isolated polyhydraminos is a poor indication of OA (1%
incidence). Ultrasound examination of the foetal neck to view the blind-ending upper pouch
and to observe foetal swallowing and magnetic resonance imaging are some of the strategies
to improve the prenatal diagnostic rate.
A nasogastric tube should be passed soon after delivery in the newborn infant of a mother
with polyhydramnios to exclude OA. Infants with OA are unable to swallow saliva and are
noted to have excessive salivation requiring repeated suctioning. At this stage, a stiff wide-
bore (10–12 French gauge) catheter should be passed through the mouth into the oesophagus,
Shahzad G. Raja
308
and certainly before the first feed. The catheter will not pass beyond 9–10 cm from the lower
alveolar ridge in OA. The tip of the catheter arrested in the superior mediastinum (T 2-4) with
gas in the stomach and intestine signifies the presence of a distal tracheooesophageal fistula
on a plain X-ray of the chest and abdomen. Isolated atresia is indicated in the absence of
gastrointestinal gas. A fine bore catheter may curl up in the upper pouch giving the false
impression of an intact esophagus or rarely it may pass through the trachea and proceed
distally into the oesophagus through the fistula. Additional anomalies such as a "double
bubble" appearance of duodenal atresia, vertebral or rib abnormalities may be visible on the
X-ray.
References
Spitz L. Oesophageal atresia. Orphanet J Rare Dis. 2007;2:24.
Achildi O, Grewal H. Congenital anomalies of the esophagus. Otolaryngol Clin North Am.
2007;40:219-44.
Patel SB, Ade-Ajayi N, Kiely EM. Oesophageal atresia: a simplified approach to early
management. Pediatr Surg Int. 2002;18:87-9.
Tsai JY, Berkery L, Wesson DE. Esophageal atresia and tracheoesophageal fistula: surgical
experience over two decades. Ann Thorac Surg. 1997;64:778-83.
4.8 Answer: D
Treatment of oesophageal atresia with "long gap" remains challenging and controversial.
Although there is lack of consensus on the definition of ―long gap‖ there is agreement that a
gap between proximal and distal oesophagus of 6.0 cm or more is regarded as too long to be
reliably closed within the first few weeks of life, even in healthy babies. Several oesophageal
substitution methods have been proposed such as oesophagocoloplasty, gastric transposition
or reversed gastric tube for cases where oesophageal anastomosis is impossible. Despite these
substitution options reconstruction of native oesophagus is accepted as the best option if
possible.
Placement of gastrostomy tube within 24 hours of birth and delaying the surgery for six
weeks can stabilize and prepare the neonate for delayed primary repair. Immediate
commencement of parenteral feeding and the initiation of dilation and stretching programme
will lengthen the upper oesophageal pouch two or three vertebral body lengths. Oesophageal
length can be further increased intraoperatively by mobilization of the proximal oesophageal
pouch up to thoracic inlet, division of the distal fistula (if one exists), and, if necessary,
performance of one or two proximal pouch oesophagomyotomies. Additional techniques may
be of required if a tension-free anastomosis cannot be performed. These include mobilization
of the distal oesophageal pouch, performance of an additional proximal oesophagomyotomy
via a right cervical incision, performance of an oesophagomyotomy on the distal pouch,
and/or the opening of the oesophageal hiatus and mobilization of a portion of the gastric
hiatus. If these manoeuvres fail to achieve a tension-free anastomosis, a cervical
oesophagostomy and a gastrostomy are performed and a colon interposition is undertaken on
another occasion.
References
Till H, Muensterer OJ, Rolle U, et al. Staged esophageal lengthening with internal and
subsequent external traction sutures leads to primary repair of an ultralong gap