Absent upper blind Pouch in a case of tracheo-esophageal fistula.

A common upper airway and digestive tract is a rare congenital anomaly that is usually fatal and its exact incidence is not known. It is a diagnostic challenge as it requires high index of suspicion. It should be considered in a neonate with respiratory distress in a non-vigorous baby requiring endotracheal intubation, which is difficult even in expert hand. We present a newborn with suspected tracheo-esophageal fistula that was diagnosed intraoperatively to have absent upper blind pouch of the esophagus and on autopsy found to have laryngeal atresia with absent vocal cords and a common aerodigestive tract continuing distally with trachea. The neonate was ventilated with endotracheal tube (ETT) placement which in retrospect we came to know that it was in the esophagus. The neonate also had associated multiple congenital anomalies of VACTERL association. The importance of teamwork between neonatologist, pediatric surgeon, anesthesiologist, and radiologist is highlighted for diagnosis and management of such rare cases.

INTRODUCTION

A common upper airway and digestive tract is a rare congenital anomaly that is usually fatal and exact incidence of which is not known. It is often associated with other multiple congenital anomalies. The diagnosis is assumed to be made if there is inability to perform endotracheal intubation of a newborn with respiratory distress in an expert hand in a neonate not cried at birth.[1] We present a newborn clinically suspected as a case of esophageal atresia with tracheo-esophageal fistula that was diagnosed retrospectively to have laryngeal atresia with absent vocal cords and a common aerodigestive tract continuing distally with trachea.

CASE REPORT

We received a spontaneous vaginally delivered male outborn baby at 35 weeks period of gestation, weighing 1900 grams to a 24-years-old primigravida with antenatal risk factors of gestational diabetes mellitus and polyhydramnios. The baby was born limp without any cry and required immediate resuscitation with bag and mask ventilation. Baby continued to have respiratory distress with copious oral secretions. Baby was intubated and shifted to NICU for mechanical ventilation. The initial intubation was reportedly difficult, and baby required frequent ET suctioning for copious secretions.

Clinically, a strong suspicion of esophageal atresia (EA) and tracheo-esophageal fistula (TEF) was made as feeding tube did not pass into the stomach. The chest X-ray revealed lower end of feeding tube going very low almost to T 6/7 level, and serial X rays revealed the feeding tube going sometimes to left side and sometimes to the right side, in retrospect, we came to know that it was in the trachea and was negotiating to left or right main bronchus. Baby also had other associated anomalies at birth i.e. imperforate anus and absent right kidney.

The evaluation with ultrasound revealed dilated left renal pelvis with non-visualized right kidney. After initial stabilization, baby was taken up for emergency surgical exploration. The newborn was then placed in the left lateral decubitus position and a right posterolateral thoracotomy was performed. Tracheo-esophageal fistula was isolated just one cm above the carina and was transfixed and ligated. The upper blind pouch of esophagus could not be localized even after extensive search. The feeding tube could not be seen or felt in the operative field on maneuvering by anesthesiologist. A trial of passing a large bore tube i.e. mucus sucker was attempted, which went through but again could not be traced in the operating field as it was going into the trachea along with the ETT. A trial of suctioning attempt on the mucus sucker made the right lung deflate with desaturation noticed by the anesthesiologist, which gave us a clue as to the connection of the upper end of esophagus with the trachea. An attempt was made by the otolaryngologist intraoperatively to negotiate the fiber-optic scope through the blind upper pouch, which was unsuccessful. Neck exploration for creating a cervical esophagostomy was carried out; however, the procedure was abandoned due to non-visualization of the upper end of esophagus. Peroperatively, we found after neck exploration that there was only one continuous hollow tube containing the ET tube. A feeding gastrostomy and sigmoid colostomy was carried out, and baby was shifted back to neonatal intensive care after the completion of surgery.

Baby was continued on ventilation and other supportive management with antibiotics, IV fluids, and inotropes. However, the baby succumbed on day 4 of life despite aggressive therapeutic and ventilatory support. Direct laryngoscopy revealed only aryepiglottic folds behind the epiglottis, no vocal cords, and there was no visible opening for the trachea suggesting a common upper airway and digestive tract. Fiber-optic scope was passed through the common opening, which revealed normal hypopharynx with normal development of the epiglottis but no evidence of true vocal cords. There was a collapsing lumen opening into a non-collapsible structure i.e. esophagus (collapsible) with absence of proximal trachea continuing with distal trachea (non-collapsible) [Figure 1]. A complete autopsy revealed laryngeal atresia with absent vocal cords and a common aerodigestive tract continuing distally with trachea [Figure 2]. There was also a solitary left kidney with high anorectal anomaly fulfilling VACTERL association.

Figure 1

Flexible fiber-optic scopy view of the upper airway showing the epiglottis superiorly, an atretic larynx anteriorly, and esophagus (hollow tube) posteriorly

Figure 2

Postmortem specimen of upper airway showing atretic larynx with no vocal cords and dilator in esophagus

DISCUSSION

Very early in the development of a fetus during the third and fourth weeks of gestation, foregut divides to form the esophagus and the trachea. For an unknown reason, sometimes, the wall does not form properly and a tracheal esophageal fistula and/or esophageal atresia may be the result.[2] Upper airway agenesis seems to result from the ventral displacement of the tracheo-esophageal septum that forms during this period and a variety of different anomalies can result, including laryngeal and tracheal atresia.

Congenital atresia of the larynx is defined as complete absence of the laryngeal lumen. The various types of atresia are the result of arrest at different stages in embryonic development. The infant with pure laryngeal atresia presents with a normal color at birth, but cyanosis rapidly develops after clamping of the umbilical cord.[3] About one-half the cases reported in the literature had other potentially fatal malformations. The vast majority of fetuses with complete larynx atresia die because the condition is not recognized and not treated immediately or because of other life-threatening anomalies.

Laryngotracheoesophageal cleft (LTEC) is a rare congenital anomaly that results from failed posterior fusion of the cricoid cartilage associated with incomplete development of the tracheo-esophageal septum. LTEC presents with increased secretions, respiratory distress, aspiration, and recurrent pulmonary infections.[4] Peroperatively, we anticipated that we might be dealing with a case of LTEC, and we had planned for a second stage repair after complete evaluation and optimal stabilization.

Suspicion for a possible esophageal atresia and trachea-esophageal fistula in our case was based on clinical presentation with copious oral secretions and failure to pass down the feeding tube. At operation we found to have an absent upper blind pouch of esophagus with a common upper airway and digestive tract continuing with trachea distally and lower end of esophagus opening into the trachea. Difficulty in locating the upper end of esophagus and deflation of right lung with desaturations while suctioning with a mucus sucker passed for locating the upper end raised a strong possibility of this rare congenital anomaly, which was established in the post-mortem. The diagnosis of congenital defect of a common upper airway and esophagus must be suspected if a newborn infant does not cry and develops severe cyanosis with respiratory distress soon after birth and an attempt for endotracheal intubation is unsuccessful even in expert hand, although such cases are diagnosed peroperatively or in autopsies.

Antenatal ultrasound findings of fetal ascites, fluid in the upper airway or enlarged and hyperechogenic lungs can raise suspicion of upper airway anatomical defects.[5] These signs may be absent as in our case in the presence of a tracheo-esophageal or a broncho-esophageal fistula because the fluid from the lungs can pass into the stomach via the fistula. Hence, in our case, an antenatal ultrasound failed to raise suspicion of a possible laryngeal atresia and tracheal agenesis.

We learnt few lessons in retrospect out of this rare case. First, multiple views of feeding tube through orogastric route on chest X-ray did not show any coiling of the tube but showed passage into left or right side (which we now know was passing into left or right main bronchus). This made us think that it was not going to be a common classical ‘C’ type TEF. Second, inability to locate the upper blind pouch of esophagus in a case of EA with TEF should raise the suspicion of a common wall of aerodigestive tract. We aim to familiarize our colleagues with this rare and challenging congenital anomaly for which a high index of suspicion and good team management is required.