The surgical management of non-malignant aerodigestive fistula

Management and outcomes in a consecutive series of patients with aero-digestive fistula at a tertiary gastro-esophageal surgery center

Aerodigestive fistula (ADF) is defined as a pathological connection between the upper digestive tract and the airway. ADF is associated with high morbidity and mortality and management is often complex. A cohort study including all patients admitted with ADF 2004-2022 at a single tertiary esophageal surgery center was performed based on prospectively collected administrative data and retrospectively collected electronic patient chart data,. Patient demographics, performance status, comorbidity, fistula characteristics, management, and outcomes in terms of morbidity and mortality were assessed in patients with ADF of three distinct types: (i) tumor overgrowth-related, (ii) various benign etiologies, and (iii) post-esophagectomy. Sixty-one patients with ADF were included in the study, 33 (54.1%) tumor overgrowth-related, six (9.8%) benign and 22 (36.1%) post-esophagectomy. In the post-esophagectomy group 15 out of 22 (68.2%) patients were diagnosed with anastomotic leakage prior to ADF diagnosis. Self-expandable metallic stents (SEMS) were used for temporary fistula sealing in 59 out of 61 (96.7%) patients, of which most received stents in both the digestive tract and airway. Temporary fistula sealing with stents was successful enabling discharge from hospital in 47 out of 59 (79.7%) patients. Definitive ADF repair was performed in 16 (26.2%) patients, of which one (6.3%) died within 90-days and 15 could be discharged home with permanently sealed fistulas. ADF is a complex condition associated with high mortality, which often requires multiple advanced interventions. SEMS can be applied in the airway and simultaneously in the digestive tract to temporarily seal the ADF as bridge to definitive surgical repair.

Tracheobronchial Surgery in Emerging Countries

Tracheobronchial surgery is widely performed in emerging countries mainly as a consequence of the high number of airway-related complications and poor management in intensive care units. This has led to great expertise in the surgical management of postintubation tracheal stenosis, and opportunity for advancing scientific knowledge. Nonetheless, tracheal stenosis has a severe impact on a patient's quality of life, is a major burden to the health system, and should be prevented. Incorporation of innovative techniques, technologies, and prospective databases should prompt earlier diagnosis and lead to fewer complications.

The therapeutic effect of stem cells from human exfoliated deciduous teeth on a rat model of tracheal fistula

Background

Tracheal fistulas (TF) can be dangerous and even fatal in patients. The current treatment is really challenging. Previous studies reported that mesenchymal stem cells (MSCs) could be used to treat respiratory tract fistulas. Stem cells from human exfoliated deciduous teeth (SHED) are considered to be MSC-like cells that may also have the potential to treat the tracheal fistulas. In this study, we investigated the therapeutic effects of SHED in rat tracheal fistula models.

Methods

A total of 80 SD rats were randomly divided into five groups: a sham-operated group, a local PBS group (L-PBS), an intravenous PBS group (I-PBS), a local SHED treatment group (L-SHED), and an intravenous SHED treatment group (I-SHED). The L-SHED and I-SHED groups were given a topical application around the fistula or an intravenous injection of 1*10⁷ SHED via the tail vein, respectively, while the L-PBS and I-PBS groups were given an equivalent volume of PBS through local or intravenous administration. A stereomicroscope was used to observe fistula healing on the 2nd, 3rd, and 5th days following transplantation. On the 7th day, the survival of SHED was observed by immunofluorescence. The pathology of the lungs and fistulas was observed by hematoxylin and eosin (H&E) and Masson staining. The expression levels of the Toll-like receptor 4 (TLR4), interleukin (IL)-1β, IL-33, and IL-4 were measured using immunohistochemistry. The expression levels of TLR4, high mobility group box 1 (HMGB1), and myeloid differentiation factor 88 (MYD88) were studied using western blotting. On day 14, airway responsiveness of rats was detected and analyzed.

Results

Fistula healing in the L-SHED and I-SHED groups was faster than that in their respective PBS groups after transplantation. The fistula diameters in the L-SHED and I-SHED groups were significantly smaller than those in the L-PBS and I-PBS groups on the 3rd day. Moreover, the phenomenon of fibroblast proliferation and new blood vessel growth around the fistula seemed more pronounced in the L-SHED and I-SHED groups. Although no discernible difference was found in airway responsiveness after SHED treatment, the degree of inflammation in the lungs was reduced by intravenous SHED treatment. However, there was no significant reduction in lung inflammation by local SHED treatment. The expression levels of IL-1β and IL-33 were decreased in the I-SHED group, while IL-4 was elevated compared with the I-PBS group. Interestingly, intravenous SHED treatment inhibited the activation of HMGB1/TLR4/MYD88 in the lung tissues of TF rats.

Conclusions

SHED transplantation accelerated the rate of fistula healing in rats. Intravenous SHED treatment reduced lung inflammation. Thus, SHED may have potential in the treatment of tracheal fistula, providing hope for future therapeutic development for TF.

[Esophagotracheal and esophagobronchial fistulas]

Esophagobronchial and esophagotracheal fistulas are rare but complex diseases with a heterogeneous spectrum of underlying etiologies. Common causes are locally advanced tumors of the esophagus and larynx, traumatic perforation from the esophageal or tracheal side as well as postoperative fistulas. The management of esophagotracheal and esophagobronchial fistulas always involves different health care providers and in most cases patients require a multidisciplinary treatment on the intensive care unit. The therapeutic concept primarily depends on the underlying cause, localization and size of the fistula but decision making is also influenced by the severity of the course of sepsis and the extent of the respiratory dysfunction. Endoscopic management with esophageal and/or tracheobronchial stenting is the most common treatment. Surgical reconstructive procedures are predominantly reserved for patients with a treatment refractory fistula or a septic multiple organ failure. The prognosis is particularly influenced by the underlying disease.

Regenerative medicine approaches for the management of respiratory tract fistulas

Respiratory tract fistulas (or fistulae) are abnormal communications between the respiratory system and the digestive tract or the adjacent organs. The origin can be congenital or, more frequently, iatrogenic and the clinical presentation is heterogeneous. Respiratory tract fistulas can lead to severely reduced health-related quality of life and short survival. Therapy mainly relies on endoscopic surgical interventions but patients often require prolonged hospitalization and may develop complications. Therefore, more conservative regenerative medicine approaches, mainly based on lipotransfer, have also been investigated. Adipose tissue can be delivered either as unprocessed tissue, or after enzymatic treatment to derive the cellular stromal vascular fraction. In the current narrative review, we provide an overview of the main tissue/cell-based clinical studies for the management of various types of respiratory tract fistulas or injuries. Clinical experience is limited, as most of the studies were performed on a small number of patients. Albeit a conclusive proof of efficacy cannot be drawn, the reviewed studies suggest that grafting of adipose tissue-derived material may represent a minimally invasive and conservative treatment option, alternative to more aggressive surgical procedures. Knowledge on safety and tolerability acquired in prior studies can lead to the design of future, larger trials that may exploit innovative procedures for tissue processing to further improve the clinical outcome.

Direct and indirect CT imaging features of esophago-airway fistula in adults

Background

Esophago-airway fistula (EAF) is an abnormal connection between the esophagus and the trachea or a major bronchus. While contrast esophagography remains the primary radiographic tool for the diagnosis of EAF, computed tomography (CT) is often employed in its evaluation. A systematic analysis of CT findings of EAF in adults has not been previously published. The goal of our study is to determine the direct and indirect CT findings of EAF in adults.

Methods

We identified patients with EAF detected on CT at our institution between January 1, 2001 and December 31, 2019, with endoscopic or surgical confirmation. We collected patient clinicopathologic characteristics and assessed CTs for direct and indirect imaging features of EAF in these patients.

Results

Twenty-six patients (median age: 56 years; range, 25–79 years; F=13, 50% and M=13, 50%) with confirmed EAF were identified. Half of the patients had an underlying malignancy. On CT, a direct connection between the esophagus and the airway was identified in most cases (22/26; 85%). Common indirect CT findings of EAF included esophageal wall thickening (21/26, 81%), mediastinal fatty stranding (21/26, 81%), airway wall thickening (20/26, 77%), fluid or debris within the airways (17/26, 65%), and focal or diffuse esophageal dilation with air (17/26, 65%). Mediastinal fluid collections were infrequently seen (4/26, 15%), but findings of aspiration or other pneumonia were common (19/26, 73%).

Conclusions

CT plays an essential role in both the primary and secondary evaluation of adult EAF resulting from both malignant and benign etiologies. CT may be the first diagnostic exam to suggest and detect the presence of EAF and may precede clinical suspicion, and it can detect a subset of fistulas not demonstrated on esophagography. There are several direct and indirect imaging findings on CT that can help in the detection of EAF.

[Surgical treatment of esophagotracheal and esophagobronchial fistulas]

BACKGROUND

Esophagotracheal and esophagobronchial fistulas are pathological communications between the airway system and the digestive tract, which often lead to major pulmonary complications with a high mortality. Endoscopic treatment is the primary therapeutic approach; however, in cases of failure early surgical treatment is obligatory.

METHODS

This article describes the clinical course of patients with esophagotracheal and esophagobronchial fistulas treated in this hospital over a period of 10 years. Patients were retrospectively analyzed with respect to the etiology of fistulas, management, in particular to the operative procedures, complications and outcome.

RESULTS

Between 2009 and 2019, a total of 15 patients with esophagotracheal and esophagobronchial fistula were treated in this hospital. Of these 12 underwent an endoscopic intervention, of which 5 were successful. In total, eight patients needed surgical intervention, six of the eight surgically treated patients recovered fully, one had a recurrent fistula, which was successfully treated by subsequent endoscopy after surgery and one patient died.

DISCUSSION

Management of esophagotracheal and esophagobronchial fistulas is challenging. This retrospective analysis reflects the published data with a success rate of endoscopic treatment in approximately 50%. Surgical intervention should be carried out after unsuccessful endoscopic treatment or if endoscopic treatment is primarily not feasible. Direct closure with resorbable sutures or reconstruction with alloplastic or allogeneic material should be preferred. For larger defects or high proximal esophagotracheal fistulas local transposition of muscular flaps or free muscular flaps play a major role. During operative closure of high intrathoracic or cervical fistulas, intraoperative neuromonitoring can be useful to prevent nerve damage.