Agenesis of the trachea: phenotypic expression of a rare cause of fatal neonatal respiratory insufficiency in six patients

Current Strategies for Tracheal Replacement: A Review

Airway cancers have been increasing in recent years. Tracheal resection is commonly performed during surgery and is burdened from post-operative complications severely affecting quality of life. Tracheal resection is usually carried out in primary tracheal tumors or other neoplasms of the neck region. Regenerative medicine for tracheal replacement using bio-prosthesis is under current research. In recent years, attempts were made to replace and transplant human cadaver trachea. An effective vascular supply is fundamental for a successful tracheal transplantation. The use of biological scaffolds derived from decellularized tissues has the advantage of a three-dimensional structure based on the native extracellular matrix promoting the perfusion, vascularization, and differentiation of the seeded cell typologies. By appropriately modulating some experimental parameters, it is possible to change the characteristics of the surface. The obtained membranes could theoretically be affixed to a decellularized tissue, but, in practice, it needs to ensure adhesion to the biological substrate and/or glue adhesion with biocompatible glues. It is also known that many of the biocompatible glues can be toxic or poorly tolerated and induce inflammatory phenomena or rejection. In tissue and organ transplants, decellularized tissues must not produce adverse immunological reactions and lead to rejection phenomena; at the same time, the transplant tissue must retain the mechanical properties of the original tissue. This review describes the attempts so far developed and the current lines of research in the field of tracheal replacement.

Tracheal Agenesis: Vertical Division of the Native Esophagus - A Novel Surgical Approach and Review of the Literature

INTRODUCTION

Tracheal agenesis (TA) is rare and usually fatal. Few survivors with concomitant tracheoesophageal fistulae (TEF) who underwent ligation of the distal esophagus with creation of a spit-fistula and neo-trachea from the proximal esophagus exist. We report a novel surgical technique whereby the esophagus is divided longitudinally to preserve a functional alimentation tract and a parallel neo-trachea. We review the literature of reported cases, including survivors beyond 12 months.

METHODS

Case report and literature review.

RESULTS

A female infant with prenatal polyhydramnios was born at 35 weeks gestation with immediate respiratory distress and absent cry. Oxygenation was maintained with a laryngeal mask airway. Despite a normal appearing larynx, she could not be intubated and emergent neck exploration disclosed no cervical trachea. The patient was placed on extra corporeal membranous oxygenation (ECMO), and later diagnosed with TA, Floyd Type I. Parental desire for reconstruction but refusal of a spit-fistula necessitated a novel procedure. The esophagus was divided longitudinally via a microstapler to preserve the original alimentary tract and create a parallel neo-trachea originating from the TEF and terminating as a cervical stoma. The healing process was complicated but the baby was ultimately discharged to home where she developed normally neurologically until succumbing one night to accidental decannulation at 16 months of age.

CONCLUSION

We describe a novel surgical approach to manage TA. This includes avoiding creation of a spit fistula and preserving the native esophagus. We then survey the literature, reporting the survivorship duration and operative management of 174 reported cases of TA.

Unexpected tracheal agenesis with prenatal diagnosis of aortic coarctation, lung hyperecogenicity and polyhydramnios: a case report

Background

Tracheal agenesis (TA) is a rare disorder usually diagnosed prenatally when a congenital high airway obstruction syndrome (CHAOS) is identified. We present a case of unexpected TA in a neonate without prenatal diagnosis of airway obstruction, with a difficult management at birth. Moreover, we discuss about differential diagnosis, classification and treatment issues.

Case presentation

A 2280 g female neonate was born at 35 week gestational age (GA) with prenatal diagnosis of aortic coarctation, polyhydramnios and diffuse hyperechogenicity of the right lung. At birth, the neonate had no audible cry, no air entry to the lungs, and hypotonia. Tracheal intubation was unsuccessful, and no visualization of the trachea was obtained when tracheostomy was attempted. Post-mortem examination showed tracheal agenesis associated with tracheoesophageal fistula and revealed no cardiologic malformations. Aortic coarctation had been suspected prenatally because of the first portion of the descendent thoracic aorta being compressed by a fibrous band connecting the proximal and distal tracheal branches. CHAOS had not developed due to the tracheoesophageal fistula (TOF).

Conclusions

TA is not always diagnosed in the fetus and it may present unexpectedly making the neonate’s management at birth critical. An effective rescue temporary oxygenation may be obtained with mask ventilation or oesophageal intubation in those cases of TA associated with a TOF. We suggest to consider a fetal magnetic resonance imaging (MRI) when the association polyhydramnios/lung hyperechogenicity occurs, even in the absence of CHAOS or other malformations. Once a diagnosis is provided, the mother should be transferred to selected centres where an ex-utero intrapartum procedure (EXIT) can be attempted. Moreover, despite high mortality, different surgical management are described to improve survival.

EXIT (ex utero intrapartum treatment) in a growth restricted fetus with tracheal atresia

Congenital high airway obstruction syndrome (CHAOS) encompasses a heterogeneous group of pathologies leading to poor lung development and difficulty oxygenating the newborn after delivery. While previously uniformly fatal, the ex utero intrapartum therapy (EXIT) procedure has provided a method to treat these patients and provide an airway to potentiate survival. We present a patient diagnosed prenatally with CHAOS secondary to tracheal atresia complicated by severe intra-uterine growth restriction (IUGR) who was successfully delivered via an EXIT procedure at 33-weeks. Multidisciplinary care and planning is paramount.

Clinical presentation and airway management of tracheal atresia: A systematic review

OBJECTIVES

Tracheal atresia (TA) is a rare congenital condition that typically requires an unexpected and emergent resuscitation in the delivery room. The mortality rate associated is very high, with only a few long-term survival cases reported. We describe the findings of a systematic review on the clinical presentation and airway management of TA.

METHODS

Using the keywords "tracheal atresia", "tracheal agenesis" and "tracheal hypoplasia" a search through Embase and Pubmed databases was performed following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) protocol. Articles published from 1950 to 2015 in English, French, Italian, Portuguese and Spanish were included. Exclusion criteria were cases of stillborn, and unclear diagnosis or outcome.

RESULTS

149 cases of TA were identified after reviewing 1125 initial references. There was a male preponderance (65%), and associated malformations were described in 94.2% of patients. Prenatal ultrasound was abnormal in 56.3% of cases, with polyhydramnios being the most common finding. The most frequent type of TA was Faro Type C. 94 (41.3%) patients did not survive beyond the first 24 h of life. Only 13 (8.4%) patients survived more than three months of life, after undergoing a variety of surgical approaches.

CONCLUSION

This review, which to our knowledge is the largest one to date, confirms that TA is a rare malformation, occurs more frequently in males, and has a very high mortality rate. Depending on the presence and type of concomitant malformation, as well of the length of the remaining trachea, different surgical management options are described.

[CHAOS in neonatal emergency care? : Tracheal agenesis in the obstetric theatre]

Tracheal agenesis (TA) is a very rare congenital malformation of unknown aetiology. It is often associated with polymalformative syndromes; the neonates commonly present a critical condition during post-natal treatment. Pathology revolves around the triad of aphonia, respiratory distress syndrome and impossibility of endotracheal intubation. In contrast to the most important differential diagnosis, i. e., congenital high airway obstruction syndrome (CHAOS), surgical airway management is also impossible due to the absence of tracheal structures. In most cases, prognosis is very poor. The case report at hand portrays the treatment of a neonate suffering from tracheal agenesis.

Long-term outcomes of four patients with tracheal agenesis who underwent airway and esophageal reconstruction

PURPOSE

The aim of this study was to evaluate the long-term outcomes of four patients with tracheal agenesis who underwent airway and esophageal/alimentary reconstruction.

MATERIALS AND METHODS

We reviewed the medical records of four long-term survivors of tracheal agenesis and collected the following data: age, sex, type of tracheal agenesis, method of reconstruction, nutritional management, and physical and neurological development.

RESULTS

The patients consisted of three boys and one girl, who ranged in age from 77 to 109months. The severity of their condition was classified as Floyd's type I (n=2), II (n=1), or III (n=1). Mechanical respiratory support was not necessary in any of the cases. Esophageal/alimentary reconstruction was performed using the small intestine (n=2), a gastric tube (n=1), and the esophagus (n=1). The age at esophageal reconstruction ranged from 41 to 55months. All of the cases required enteral nutrition via gastrostomy. Three of the patients were able to swallow a small amount of liquid and one was able to take pureed food orally. The physical development of the subjects was moderately delayed-borderline in childhood. Neurological development was normal in two cases and slightly delayed in two cases.

CONCLUSIONS

None of the long-term survivors of tracheal agenesis required the use of an artificial respirator, and their development was close to normal. Future studies should aim to elucidate the optimal method for performing esophageal reconstruction to allow tracheal agenesis patients to achieve their full oral intake.

TACRD and VACTERL associations in a fetus: case report and review of the literature

Tracheal agenesis is a rare and potentially lethal congenital anomaly. The incidence is less than 1/50,000, with a male:female ratio of 2:1. We report the case of a male fetus with complete agenesis of the trachea and a tracheoesophageal fistula arising from the esophagus that connected through the carina, as well as several abnormalities (congenital cardiac abnormalities, duodenal atresia, vertebral defects, anal atresia, renal defects, limb defects, and diaphragmatic hernia). To our knowledge, few cases of infants with VACTERL or TACRD association have been reported to date. Here, we report a new case of a fetus that showed the full range of VACTERL and TACRD associations.

Tracheal agenesis with tracheoesophageal fistulae: fetal MRI diagnosis with confirmation by ultrasound during an ex utero intrapartum therapy (EXIT) delivery and postdelivery MRI

Tracheal agenesis is a rare and essentially lethal anomaly with divergent prenatal imaging findings depending on the presence or absence of a tracheoesophageal fistula. All prenatally diagnosed cases of tracheal agenesis reported to date have not had a tracheoesophageal fistula and presented with thoracoabdominal findings similar to congenital high airway obstruction syndrome. We present the case of a 32-week gestation fetus with rapid onset of polyhydramnios and no persistent findings of congenital high airway obstruction syndrome that was ultimately diagnosed with tracheal agenesis plus tracheoesophageal fistula by fetal MRI. Additionally, we present the novel uses of intraoperative US during a staged ex utero intrapartum therapy delivery and postdelivery MRI, facilitated by proximity within the neonatal ICU, to confirm diagnosis and direct patient management while minimizing unnecessary investigations.

Tracheal agenesis: approach towards this severe diagnosis. Case report and review of the literature

Tracheal agenesis (TA) is a severe congenital disorder with often an unexpected emergency presentation. There is complete or partial absence of the trachea below the larynx, with presence or absence of a tracheoesophageal fistula (TOF). A neonate with TA is described, and another 48 cases found in literature are reviewed. Due to absence of a TOF, five cases were diagnosed prenatally because of congenital high airway obstruction syndrome (CHAOS). When a TOF is present, polyhydramnion and several other congenital malformations seen on the ultrasound examination should alert clinicians of potential tracheal problems. Prenatal magnetic resonance imaging (MRI) may provide a definitive diagnosis. Postnatal diagnosis is based on recognition of specific clinical signs in the newborn with TA: respiratory distress with breathing movement without appropriate air entry, no audible cry, and failed endotracheal intubation. Despite progress in surgical interventions, mortality remains high. Prenatal diagnosis of TA is possible, but only if a TOF is absent resulting in CHAOS. Prenatal diagnosis of polyhydramnion and other congenital malformation should alert clinicians of potential tracheal problems. Prenatal MRI may provide a definitive diagnosis.

Prenatal diagnosis of type 1 tracheal agenesis without tracheoesophageal fistula

Tracheal agenesis is a rare and uniformly lethal congenital malformation. We recently had the opportunity to diagnose prenatally a case of type I tracheal agenesis without fistula in a 22-week-old fetus, in which the hyperechogenicity of the enlarged lungs was associated with ascites, and tracheal dilatation in the lower half. We report the ultrasonographic and autopsy findings and review the literature on this rare condition to contribute to the understanding of type 1 tracheal agenesis without tracheoesophageal fistula.

Failed resuscitation of a newborn due to congenital tracheal agenesis: a case report

Tracheal agenesis is a rare congenital condition. It usually presents as an unexpected emergency during resuscitation of a newborn in the delivery room. The condition is almost always fatal in the resuscitation phase, but also when the neonate survives the long term prognosis remains poor. We present a case of tracheal agenesis, discuss its presenting symptoms and possibilities for antenatal diagnosis and review the therapeutic options.

Failed resuscitation of a newborn due to congenital tracheal agenesis: a case report

Tracheal agenesis is a rare congenital condition. It usually presents as an unexpected emergency during resuscitation of a newborn in the delivery room. The condition is almost always fatal in the resuscitation phase, but also when the neonate survives the long term prognosis remains poor. We present a case of tracheal agenesis, discuss its presenting symptoms and possibilities for antenatal diagnosis and review the therapeutic options.

A case of tracheal agenesis surviving without mechanical ventilation after external esophageal stenting

Tracheal agenesis is a rare and usually lethal congenital malformation of the forgut. Although some infants can be resuscitated with an intra-esophageal intubation temporarily, long-term airway management is difficult because of the collapsing airway. We report a long-term survivor with tracheal agenesis in whom a Gortex external esophageal stent using radial traction sutures was applied to prevent the esophagus from collapsing. The patient was discharged from our hospital without mechanical ventilation or oxygen inhalation at 10 months of age. Our procedure has a potential to establish a long-term steady airway in patients with tracheal agenesis. The detail of the procedure is presented and the related literature is reviewed.

Bmp4 is required for tracheal formation: a novel mouse model for tracheal agenesis

Tracheal agenesis/atresia (TA) is a rare but fatal congenital disease in which the breathing tube fails to grow. The etiology of this serious condition remains largely unknown. We found that Bmp signaling is prominently present in the anterior foregut where the tracheal primordium originates and targeted ablation of Bmp4 (Bmp4(cko)) resulted in a loss-of-trachea phenotype that closely resembles the Floyd type II pathology, the most common form of TA in humans. In Bmp4(cko) embryos, tracheal specification was not affected; however, its outgrowth was severely impaired due to reduced epithelial and mesenchymal proliferation. In agreement, we also observed significant reduction in the expression of Cyclin D1, a key cell cycle regulator associated with cellular proliferation. However, the proliferative effect of Bmp signaling appears to be independent of Wnt signaling. Interestingly, we found significantly reduced expression of activated extracellular signal-regulated kinase (Erk) in the Bmp4(cko) ventral foregut, suggesting that Bmp signaling promotes Erk phosphorylation which has been associated with cellular proliferation. This study provides the first evidence linking Bmp signaling to tracheal formation by regulating the proliferative response of the anterior ventral foregut. Our finding sheds light on human tracheal malformations by providing a novel mouse model implicating Bmp signaling, non-canonical Erk activation and cellular proliferation.

[Tracheal agenesis associated with laryngeal malformations as an unusual cause of airway failure]

Tracheal agenesis is an uncommon congenital malformation with an extremely high mortality rate. This malformation manifests after delivery as severe respiratory distress, cyanosis, lack of crying and impossibility of endotracheal respiratory support. This anomaly is usually associated with cardiovascular, respiratory and gastrointestinal malformations. Only a high index of suspicion and early surgical management will prevent death. An early diagnosis may also help the parents and the medical team to take appropriate decisions. Currently, there is no effective therapy that guarantees long-term survival.

Three new cases of congenital agenesis of the trachea

Congenital absence of the trachea is a rare anomaly that might confront the obstetrician or neonatologist with an unexpected emergency. These patients present with cyanosis, severe respiratory distress, insufficient gas exchange, absence of audible crying and difficult or impossible endotracheal intubation. In more than 90% it is associated with further congenital malformations. Adequate oxygenation depends on the existence of a tracheo- or bronchooesphageal fistula and the length of the proximal trachea. We present the cases of three neonates with tracheal agenesis with tracheooesophageal fistula. Two of the neonates died within the first hour of life because endotracheal intubation was impossible and oxygenation through an oesophageally placed tube was insufficient. The third infant could be oxygenated through a tracheooesophageal fistula. The ventilation was at least insufficient and no surgical intervention was made. The diagnosis of a congenital absence of the trachea usually is made after birth because of the clinical signs and the course within the first minutes of life. The only way that the diagnosis can be made prenatally is by magnetic resonance imaging (MRI). The knowledge of this clinical picture helps to make decisions in an unexpected emergency in the immediate postpartum period and also in patients whose ventilation is very difficult right from the start.