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ORIGINAL ARTICLE
Year : 2017  |  Volume : 6  |  Issue : 4  |  Page : 225-230

Clinical profile and short-term outcome of neonates with esophageal atresia and tracheoesophageal fistula at tertiary care center in a developing country: A 25-year experience


1 Department of Paediatric Surgery, PGIMS, Rohtak, Haryana, India
2 Department of Paediatrics, PGIMS, Rohtak, Haryana, India

Date of Web Publication17-Oct-2017

Correspondence Address:
Kamal Nain Rattan
Department of Paediatric Surgery, PGIMS, Rohtak - 124 001, Haryana
India
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/jcn.JCN_44_17

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  Abstract 

Background: Despite the advancements in antenatal diagnostic and postnatal management in neonates with esophageal atresia (EA)/tracheoesophageal fistula (TEF) resulting in better survival rates in the developed world, the outcome still remains poor in developing countries. Materials and Methods: Retrospective analysis of medical records of neonates who were operated for EA/TEF from 1991 to 2015 at our center was done. Results: A total of 693 neonates were operated during the study period with male-to-female ratio 1.9:1. Mean birth weight was 2300 ± 840 g and mean gestational age was 36 ± 4 weeks. Prenatal diagnosis with ultrasonography screening was done in only 9% cases. Mean age of neonates at referral was 4.3 ± 1.5 days. Frothing from mouth and tachypnea were the most common presenting features seen in 94% and 78% neonates, respectively. Type III EA was the most common variety seen. Incidence of associated anomalies was 52% with congenital heart disease being most common. Overall postoperative survival rate of 57% was observed. In the past 10 years of study, survival improved to 64% in comparison to 48% during initial 15 years. Poor prenatal supervision, aspiration pneumonia, prematurity, low birth weight, delayed referral and inadequate transport facilities, associated congenital anomalies, and lack of advanced Neonatal Intensive Care Units (NICUs) facilities were the important contributing factors for high mortality. Conclusion: In developing countries, only improving the NICUs and surgical techniques will not deliver a better outcome in neonates with EA/TEF. Emphasis should be on the strengthening of peripheral health services and transport facilities to achieve good survival rates.

Keywords: Esophageal atresia, neonate, survival, tracheoesophageal fistula


How to cite this article:
Rattan KN, Singh J, Dalal P. Clinical profile and short-term outcome of neonates with esophageal atresia and tracheoesophageal fistula at tertiary care center in a developing country: A 25-year experience. J Clin Neonatol 2017;6:225-30

How to cite this URL:
Rattan KN, Singh J, Dalal P. Clinical profile and short-term outcome of neonates with esophageal atresia and tracheoesophageal fistula at tertiary care center in a developing country: A 25-year experience. J Clin Neonatol [serial online] 2017 [cited 2017 Nov 24];6:225-30. Available from: http://www.jcnonweb.com/text.asp?2017/6/4/225/216907




  Introduction Top


Described first in 1697 by Thomas Gibson, esophageal atresia (EA) is a congenital malformation, in which the esophageal continuity is interrupted, leading to the formation of an upper and lower segment.[1] Estimated incidence is 1 in 2500–3000 live births and the majority of cases are sporadic.[2] In approximately 86% of cases, the distal esophageal pouch communicates with the trachea, in 7% of cases, there is no fistulous communication, whereas, in 4%, there is a tracheoesophageal fistula (TEF) without atresia.[3] Although the exact mechanism is still obscure, any defect in the migration of the lateral folds or growth arrest at the time of evagination in foregut is thought to be underlying etiology.[4] Around half of newborns with EA/TEF are associated with other congenital anomalies.[3] Several syndromic phenotypic variants, for example, vertebral, anorectal malformations, cardiac defects, TEF with or without EA, renal malformations, and limb defects (VACTERL/VATER) and rarely, Di-George syndrome, Holt-Oram syndrome, polysplenia, and Pierre Robin syndrome association had been reported.[5] Open or thoracoscopic surgical approaches are the treatment modalities of choice. The aim of this study is to highlight the fact that despite advancements in management techniques resulting in better survival in the developed world, the outcome still remains poor in resource-constrained countries.


  Materials and Methods Top


The medical records of all neonates admitted with EA/TEF at our tertiary care center between 1991 and 2015 were reviewed. We analyzed prenatal screening, age of neonate at referral, gender, birth weight, place of delivery, period of gestation, feeding practices, condition of patient on arrival at our center, surgical interventions, type of EA/TEF (as per Gross's classification), peroperative findings, associated congenital anomalies, and final outcome of the patient. Fifty-five patients who could not be operated due to refusal of parents to consent for surgery were excluded from the study. Primary outcome, i.e., survival was defined when a neonate is discharged from the hospital on oral feed postoperatively.

In the past 10 years of study (2006–2015), with start of new health policies emphasizing on maternal and neonatal health quality development, there was improvement in infrastructure of peripheral health facilities as well as referral institutes in our country. During this period, there was better availability of prenatal ultrasonography (USG) screening, trained birth attendants at peripheral hospitals, better neonatal transport services, and increased preference of institutional deliveries. Hence, we had compared the postoperative survival rates of initial 15 years (i.e., from 1991 to 2005) with the past 10 years (i.e., from 2006 to 2015).

Waterston's prognostic classification was used for comparison of the survival in the postoperative period. This classification identifies following three categories:[6]

  1. Group A: Birth weight >2500 g and healthy
  2. Group B: Birth weight 1800 to 2500 g and healthy or higher birth weight but moderate pneumonia and other congenital anomalies
  3. Group C: Birth weight <1800 g or birth weight >1800 g but severe pneumonia and cardiac anomaly.


Statistical analysis

Statistical analysis was done using Epi-Info™ software package developed by the United States of America Centers for Disease Control. Chi-square test was employed to find out the association between the two variables, and odds ratio (OR) was calculated for determining the strength of association along with 95% confidence interval (CI). Statistical significance was considered when P < 0.05.


  Results Top


Demographic details

In a total of 693 operated neonates, male-to-female ratio was 1.9:1 and mean birth weight was 2300 ± 840 g with lowest birth weight 900 g. Mean maternal age was 24.1 ± 4.3 years (range 19–31 years). Mean gestation age was 36 ± 4 weeks with 58% neonates born at term gestation (≥37 weeks). Only 9% (62) patients were prenatally suspected of having EA/TEF with USG screening. All of these prenatally detected patients were referred in utero to the referral center. Seventy-seven percent neonates were delivered at the hospitals where pediatricians were not available.

Presentation

Average age at the time of referral was 4.3 ± 1.5 days in our study. We had received 13% neonates within first 24 h, 34% neonates between 1 and 2 days, 48% between 3 and 5 days, and 5% beyond the 5th day of life. The most delayed diagnosis was made in a 21 days old neonate, in which esophageal pouch perforation had occurred. The most common presentation was frothing from mouth in 94%, followed by respiratory distress in 78% and regurgitation of feeds in 45% neonates. Because the anomaly was not identified at the time of birth, these neonates were discharged from hospital and feeding was attempted in 77% of the neonates. Twenty percent of neonates were in the state of shock and 36% were hypothermic at the time of arrival in the emergency room.

Diagnosis

Prenatally, history of polyhydramnios was observed in 71% pregnancies. However, only 9% neonates were diagnosed with EA/TEF prenatally, all of them during the past 10-year study period. A chest radiograph with the red rubber tube in situ was the most common diagnostic tool and confirmed the diagnosis in 100%. The chest radiograph was also helpful in depicting the pulmonary status of the infant. In our series due to missing the diagnosis at the time of birth, a significant number of neonates (77%) were fed. Feeding and pooling of oral secretions had led to the development of aspiration pneumonia in approximately 60% of neonates. In three patients, Gastrografin study was performed to support diagnosis where perforation of the upper esophageal pouch was suspected.

Associated congenital anomalies

Out of total 693 operated patients, 364 (52%) neonates were found to have other congenital anomalies. Congenital heart diseases (CHD) were the most common, seen in 36% neonates. Among the spectrum of the CHDs, the ventricular septal defect (VSD) was seen in 54%, both atrial septal defect and VSD in 23%, complex cyanotic heart disease was seen in 11%, tetralogy of Fallot's in 8%, blood vessel anomalies in 4%, and dextrocardia in 2 patients. Right-sided aortic arch was present in 3.4% (24/693) neonates. Skeletal anomalies were observed in 21% neonates. Vertebral, anorectal malformations, cardiac defects, TEF with or without EA, renal malformations, and limb defect (VACTERL/VATER) association were present in 12.3% (45/364) neonates. The genitourinary system was affected in 18% with a spectrum of renal agenesis or dysplasia, polycystic kidney, ureteral and urethral malformations, and hypospadias. Gastrointestinal tract malformations and facial anomalies (such as the preauricular skin tag, cleft lip and cleft palate) were observed in 12% neonates and 7%, respectively. Hydrocephalus was found to be associated with two cases of TEF.

Management and peroperative findings

The average age for surgical intervention was 4.9 days of life. All of the neonates were stabilized hemodynamically before taking for surgery. Primary repair was performed in 81% and staged repair in 19% cases. The surgery was performed through right-sided thoracotomy in all patients. Duration of surgical procedure was 50–60 min in our series. However, in 42 neonates, surgery was prolonged beyond 2 h. Postoperatively, the neonates were ventilated as needed, nasogastric or gastrostomy feedings were initiated upon hemodynamic stabilization. Right-sided aortic arch was seen in 24 neonates. Type III fistula was most common to be seen in 87% of neonates followed by Type I in 11%. Type H type and double fistula were observed in 1% each.

Postoperative morbidity and mortality

Average duration of postoperative hospital stay was 14.4 ± 5.1 days. Sepsis was the leading cause of postoperative morbidity seen in 20%, minor anastomotic leak in 14%, and major anastomotic leak in 8% cases. All of them were managed conservatively with intravenous antibiotics and mediastinal drainage; only 1% patients required the second surgery. On the 8th postoperative day, contrast studies were done to rule out any anastomotic leakage. Patients were discharged once oral feeds were established.

Postoperative survival

Postoperative survival rate in our cohort was 57% (395/693). Using Waterston's prognostic criteria, most favorable postoperative survival rate of 98% was observed in category A as compared with 59% in category B and 15% in category C [Figure 1]. Postoperative survival rate was 80% (325/404) in term infants as compared to only 24% (70/289) in preterm infants. We observed a significant association between survival with gestation (OR: 3.87, 95% CI: 2.875–5.222, P < 0.01) and birth weight (P< 0.01). In 62 prenatal diagnosed cases, 51 (82%) neonates survived. Association between day of life at the time of referral and survival was also found significant as delayed referrals (beyond initial 48 h) were associated with poor outcome (P< 0.01). Forty-three percent (57/138) of the neonate with shock at presentation survived to discharge. (OR: 1.85, 95% CI: 1.268–2.702, P < 0.01). Similarly, 49% (122/249) neonates with hypothermia survived (OR: 1.66, 95% CI: 1.214–2.273, and P < 0.01), although stay was significantly prolonged (with an increase of mean duration >2.5 days) in these hypothermic neonates. Forty percent neonates expired in whom aspiration pneumonia and severe respiratory distress were present. The neonates operated within initial 48 h of life, had postoperative survival of 82% (194/245) as compared to 45% (201/448) among those who were operated beyond 48 h period (OR: 4.67, 95% CI: 3.260–6.701, P < 0.01). A total of 61% neonates expired, in whom one or more congenital anomalies were found. The survival was the worst when CHDs were found to be associated with EA/TEF. Postoperative survival was inversely related to the gap between the esophageal segments, as it was 87% (135/155) in neonates with the shorter gap (<2 cm) as compared to 48% (260/538) in neonates with a longer gap (OR: 7.21, 95% CI: 4.381–11.889, P < 0.01). In 42 neonates who had prolonged surgery beyond 2 h, twenty (47.6%) patients survived. Incidence of injury to surrounding structures (e.g., trachea, bronchus, and blood vessels) was 1.5% (10/693) in our series, out of these four neonates expired. Out of 152 neonates who developed anastomotic leakage, 21% (32/152) expired due to postoperative sepsis.
Figure 1: Postoperative survival according to Waterston's prognostic classification (n = 693)

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We had compared the overall survival rates between time periods from (1) the years 1991 to 2005 and (2) years 2006 to 2015 [Table 1]. The survival rate had improved to 64% in the past decade of study as compared to 48% seen in initial 15 years.
Table 1: Comparison of postoperative survival in different Waterston's groups between 1991-2005 and 2006-2015

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  Discussion Top


EA/TEF is one of the most serious congenital anomalies that mandates urgent surgical intervention. First successful surgery in a neonate with EA/TEF was performed in 1941 by Camroon Haight.[7] Since that time, a lot of improvement in management had been made, and postoperative survival rate of >90% had been achieved in the developed world.[8] Several prognostic classifications were proposed, but oldest and most widely used is Waterston's risk classification (1962). Due to recent therapeutic advancements, this classification system was revised by Spitz et al. and later by Poenaru et al.[9],[10]

The overall postoperative survival rate in our study was 57%. This was significantly low as compared to developed countries. In many parts of the world, survival rates of 100% had been achieved with Waterston Group A.[8],[11],[12],[13],[14],[15],[16] Similarly, the prognosis of Group B had also improved from reported 68% to >90%. However, in the present cohort, postoperative survival rates in both Groups B and C are still comparable to what was observed by Waterston in 1962 [Table 2]. Osei-Nketiah et al. had even reported survival rates as low as 39.7% from Ghana in 2016 depicting the poor status in third world countries.[17]
Table 2: Postoperative survival in different studies using Waterston's classification

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Among various risk factors studied, low birth weight (LBW) had an inverse relationship with survival in the present cohort. Survival improved significantly to 75% in infants with birth weight >2500 g. As most of the LBW neonates tend to be preterm also, prematurity was also contributing factor to mortality. Aspiration pneumonia was another important factor affecting survival. Most of the infants were delivered at peripheral hospitals where pediatricians were not available. Due to lack of awareness about congenital anomalies among birth attendants, these patients often remained undiagnosed. Isolated case reports from India are available where EA/TEF remained undiagnosed even up to 7 days of life.[19],[20],[21],[22] Moreover, at home, feeding may be attempted which results in the development of aspiration pneumonia. Karakus et al. and Yagyu et al. had also reported the poor outcome in neonates with delayed diagnosis of EA/TEF.[23],[24] EA/TEF has been described to be associated with life-threatening anomalies in approximately 30%–60% cases.[4],[25] In our study, the incidence of congenital anomalies was found to be 52% (n = 364). Yang et al., had reported even higher incidence (80%) of congenital anomalies.[26] The presence of associated anomalies has implications in surgical planning, anesthetic issues, postoperative morbidity, and mortality. Poor neonatal transport facilities also contribute to significant mortality in resource-limited setup. During transport from peripheral hospitals, basic infrastructure facilities (oxygen and temperature maintenance) are lacking. Simple measures such as proper wrapping with clothes and repeated oral suction with mucous aspirator by accompanying parents can make a big difference in survival.

Peroperatively, the length of gap between the two esophageal segments and anastomotic tension, duration of surgery, aberrant blood vessels, and injury to surrounding vital structure were the significant factors determining the outcome. Upadhyaya et al. in their review had reported gap length as an independent risk factor.[27] When gap length is more, the anastomosis remained under tension and chances of leakage become very high. In our series, 14% of neonates developed minor and 8% developed major anastomotic leakage, which was significantly low as compared to a similar study from India.[26] We also observed that prolonged duration of surgery (>2 h) had affected the outcome adversely by exposing the neonate to toxic effects of anesthetic agents, hypothermia, and increased risk of sepsis.

Over the time from the year 1990–2005 to 2006–2015, we had observed improvement in survival rates. These improvements may be attributed to new health policies such as National Rural Health Mission and maternal and child health programs.[28] Under these health policies, a lot of stress had been given on improvement of the infrastructure at peripheral health services such as prenatal screening, better nutrition during pregnancy, institutional delivery, and neonatal transport system. In a study with similar settings, Sharma et al. had observed improvement in postoperative survival from 4.6% to 59% with better peripheral management.[29] Although postoperative survival rates are improving over the past few years, we are still way behind when compared to Western world. The gravity of situation is depicted from the fact that survival rate of Group C in our study still remains comparable to that observed by Waterston almost five decades ago in 1962. Hence, there is still tremendous scope for improvement, and it can be achieved by (1) better prenatal screening to have high degree of suspicion/diagnosis in favor of EA/TEF and timely referral of mother to a well-equipped center, (2) imparting basic training and increasing awareness about congenital malformations to the peripheral health workers leading to timely diagnosis with prompt referral and not exposing them to feeding, (3) well-supervised neonatal transport facilities, (4) availability of well-equipped surgical center, and (5) development of accessible Neonatal Intensive Care Units (NICUs) at peripheries.


  Conclusion Top


The majority of patients in developing countries belong to peripheral areas which have limited access to advanced diagnostic and therapeutic facilities. Merely improving the surgical facilities and NICUs services at referral centers will not deliver the better outcomes in neonates with EA/TEF. Hence, in resource-poor countries, strengthening of peripheral health services and transport facilities should be the main focus to have an improved outcome not only in newborns with EA/TEF but otherwise also.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.



 
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