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Very rare form of chondrodysplasia often leading to
death in infancy as a consequence of respiratory insufficiency caused by severe thoracic
restrictive deformation. Common association with multiple skeletal
malformations, liver, renal, and retinal dysfunction.
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Asphyxiating Thoracic Dystrophy of the Newborn; Thoracic
Pelvic Phalangeal Dystrophy.
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Congenital genetic disorder first described by Jeune et
al. in 1955.
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The incidence in the United States is estimated at
1:100,000-130,000 live births.
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Autosomal recessive, clinical variability.
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Clinically evocated at birth in a child with narrow
thorax and pelvic anomalies confirmed by radiologic findings: short ribs and
particular morphology of the pelvis (horizontal roof of the acetabulum and a
trident aspect formed by a median protrusion and two lateral spurs). The
term asphyxiating thoracic dysplasia refers to the hypoplastic thoracic cage and lungs, often resulting in
respiratory distress, asphyxia, and early death in infancy.
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Living patients present with short stature; disease
involves chest (narrow thorax, short, horizontal ribs with bulbous and irregular
ends) with pulmonary insufficiency (lung hypoplasia, restrictive syndrome,
recurrent respiratory infections). Approximately 70% die from respiratory
failure in infancy or early childhood; skeletal (lacunar skull, small pelvis with
trident acetabular roofs, sciatic notch spur, irregular metaphyses and
epiphyses, short long bones, cone-shaped epiphyses and polydactyly), GI
(hepatic and pancreatic fibrosis, polycystic liver and pancreas disease,
bile duct proliferation), and genitourinary (Potter type IV polycystic kidneys, chronic
nephritis, and renal failure). Retinal degeneration is frequent.
Hydrocephalus, cleft lip/palate, and scalp defect can be observed.
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Evaluate pulmonary function
(clinical, chest radiographs, CT, pulmonary function test, arterial blood
gases analysis) and renal, hepatic, and pancreatic function (clinical,
echography, CT, and laboratory). Request complete blood count, electrolytes,
creatinine, blood urea nitrogen, liver transaminases, bilirubin, and
coagulation tests.
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Careful intraoperative positioning is
needed because of skeletal malformations. As a result of hypoplastic chest
and lungs, high airway pressures may be required to maintain normocapnia
with normal respiratory rates and tidal volumes. Hence, small tidal volumes
and a higher respiratory rate are preferred to prevent pulmonary barotrauma
and/or pneumothorax. Cor pulmonale and pulmonary artery hypertension must be
expected, so acidosis and hypercapnia must be prevented. Both arterial and
venous access can be difficult because of limb anomalies. Regional
anesthesia is not contraindicated but can be difficult to realize because of
skeletal deformities. Postoperative mechanical ventilation must be
anticipated. If a nasogastric tube is required for surgery, be aware of the
possibility of esophageal varices caused by liver cirrhosis and portal
hypertension, which may render abdominal procedures prone to major blood
loss [secondary to coagulopathy, thrombocytopenia (hypersplenism), venous
congestion].
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Perioperative fluid regimen and the choice of
anesthetic drugs should be adapted to renal and hepatic function. In
case of failure of both systems, it is probably best to administer low doses
of anesthetic drugs and titrate to effect.
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