Caustic injuries are considered as one of the most prevalent, as well as preventable accidental injuries. Children are among the highest groups at risk of these injuries due to their curiosity and ability to reach objects without discerning their harm and potential dangers. In 2009, the Kids' Inpatient Database of the United States reported 807 cases of caustic injuries. Our study was conducted in southwest Iran, in which 57 pediatrics hospitalized patients with caustic injuries were collected during 10 years (1994–2003), demonstrating an annual rate of 5.7cases/year. In similar studies in our province, Honar et al.[15] reported 75 in 2006–2011 (12.5case/year) and Dehghani et al.[9] reported 41 cases from 2015–2016 (20.5 cases/year). This upsurge in the number of cases shows the significance of this matter and therefore, evaluating the etiology and applied managements, along with choosing the proper therapeutic option in these patients is necessary.
Among the contributing factors to this increasing number of cases per year may be the increased use, easy accessibility, and low cost of detergents and bleaches, especially in developing countries. Alkaline was considered as the most corrosive agent in this study with an incidence of 89% (50 out of 57 cases), while acid agents consisted of 9.4% (5 out of 57 cases) of the etiologies in our study population. In a similar study in our center, 64 hospitalized patients were reported to have alkaline ingestion during a 4 year period. [10] Also, in a study conducted in Australia, 74% of caustic ingestion occurred by alkaline agents.[16] Acids, regarding their low viscosity and therefore rapid transfer to the stomach and also due to their nature cause coagulation necrosis, with eschar formation that may prevent further damage and limit the injury depth. Conversely, alkalis bind to tissue proteins and lead to liquefactive necrosis and saponification, and penetrate deeper into tissues, assisted by a higher viscosity and a longer contact time through the esophagus. On the other hand, children usually tend to swallow a larger amount of alkaline because alkalis are usually odorless and tasteless; although, acidic agents have a sour taste which makes children spit them out. Another point for our region (the south of Iran) is the excessive use of air conditioner following by its cleaner that fundamentally and are made by NaOH which kept in beverage bottle without any warning label in addition to the low educational level of parents have led to increasing the occurrence of esophageal burn by caustic ingestion.
In caustic injury patients, a preliminary survey includes airway assessment as well as fluid and electrolyte balance.[11] We also administered antibiotics along with corticosteroid as medical management. Among the most imperative complications of esophageal burns is stricture. Katz et al.[8] reported esophageal stricture in more than 90% of patients with grade 3 and almost 30–70% of grade 2B caustic injury. Malignant transformation to esophageal cancer is one of the following complications of esophageal stricture.[17] Studies have also reported that esophageal stricture is associated with hiatal hernia, reflux disease, dysphagia symptoms, and causing difficulties for esophageal reconstruction. [18–20] A study in 1992 evaluated the administration efficacy of antibiotic and systemic steroids simultaneously in caustic ingestion, which concluded that antibiotics with steroids might be useful in reducing strictures in patients with esophageal burns.[21] Controversially, a controlled randomized trial revealed the corticosteroids’ ineffectiveness in preventing esophageal stricture in children with a caustic injury.[22] Therefore, novel therapeutic approaches for preventing or managing esophageal strictures that would enable a child to tolerate an oral diet in a more expeditious and less invasive manner would be highly desirable. Furthermore, the oblique cutting of the ECT facilitates feeding and also prevents unintentional aspiration.
In this report, we utilized the chest tube, as a broadly available and well-known equipment in all emergency departments, proposed as an esophageal stent for not only preventing esophageal stricture in the first 48 hours but also after dilatation. Formerly, self-expanding plastic stents (SEPS) and fully covered self-expanding metal stents (FCSEMS) have been used for stenting, and each had its advantage and disadvantage. The success rate for SEPS showed 50% by Broto et al.[23] and 75% for FCSEMS by Zhang et al.[24]
Stent migration is another common complication that has been reported from 14–48% of cases, which has been related to the type of stent [25]. Metal stents which are fully-covered with polytetrafluoroethylene (PTFE), polyurethane, or silicone have a higher chance of migration, compared with uncovered metal stents, which are held in place by hyper-granulation and mucosal ingrowth [26, 27]; nevertheless, these proliferations contribute to ulcers and struggle when removing the stent. Self-expanding plastic stents are at greater risk of migration when compared with self-expanding metal stents, which are daunted in benign esophageal stenosis due to its high incidence of necrosis and ulceration, tissue hyperplasia, new stricture or fistula formation, and the tendency for the metal portion to embed within the esophageal wall [28, 29]. Best et al. (2009) and Manfredi et al. (2014) reported high rates of mucosal ingrowth and hyper-granulation, causing difficulty in stent removal and stent-induced ulceration.[29, 30]. Since the ECT is inserted from below the cricopharyngeal till the lower esophagus sphincter and also fixed from outside of the nose, this decreases the chance of migration compared to other methods of fixation using thread and suture. Furthermore, the stent material safeguards cell proliferation into the stent, resulting in easy removal of the ECT and less complication such as esophageal ulcer and hyper-granulation.
From an economic point of view, as one of the most important factors in management decision making particularly in developing countries, the proposed ECT can be an ideal choice due to its cost-effective aspects and in centers were other esophageal stents are unavailable.
Among the other advantages of the ECT is that the patient will be able to tolerate oral feeding with soft diets as well as liquids, so the foods are based on the inlet of the ECT, which is located in the cricopharyngeus area and allows a pathway to the stomach. However, since the ECT covers the total length of the esophagus to the lower sphincter, a risk of reflux should be considered which can be managed with proper anti-reflux medication.
Among the patients in our study, 5 were satisfied with their results, while two (patients 4 and 7) had mild esophageal stenosis. Among these two, patient 4 had ECT for 90 days. The exact duration in which stents should be used is still a matter of debate. The European Society for Gastrointestinal Endoscopy Recommendations for the Stenting of Benign Esophageal Strictures acknowledges this lack of data available and suggests the insertion of self-expanding metal and plastic stents for a minimum of 6–8 weeks and no more than three months.[31] Likewise, we recommend removing the ECT after 6–8 weeks. Furthermore, patient 7 had ECT inserted after 83 days after the injury, which had already caused chronic damage and stricture. It is also worth mentioning that ECT was inserted in one of the patients with grade I of caustic injury, which was intended as prophylaxis for esophageal stenosis.
Endoscopic dilatation with balloon has been the standard of treatment for benign esophageal strictures; nevertheless, the recurrence rate was reported to be 30%-40%. [28] Increasing the victims of caustic ingestion on one hand, and the high economic burden, on the other hand, made us use the ECT in early stenting, which is more economical, broadly available, and also regarding its high efficacy.
Several caveats regarding our study deserve mention. First, this was a retrospective, single-institution series of esophageal stents deployed in a heterogeneous group of patients. Also, our series lack of control group and consists of a small sample size. This study was non-comparative and did not compare stenting to other therapeutic options. However, our study’s main focus was utilizing an already existing device, the chest tube, as an esophageal stent for the early management of caustic injury pediatrics, especially in centers with limited equipment.