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ORIGINAL ARTICLE
Year : 2021  |  Volume : 24  |  Issue : 5  |  Page : 633-639

The role of interventional pulmonology for the postoperative bronchopleural fistula


1 Department of Pulmonary Medicine, Sultan Abdulhamid Han Teaching Hospital, Istanbul, Turkey
2 Interventional Pulmonology Unit, Istanbul, Turkey
3 Department of Thoracic Surgery, Yedikule Teaching Hospital for Pulmonology and Thoracic Surgery, Istanbul, Turkey
4 Department of Pulmonary Medicine, School of Medicine, Istanbul Bilim University, Istanbul, Turkey

Date of Submission11-Nov-2019
Date of Acceptance04-Aug-2020
Date of Web Publication20-May-2021

Correspondence Address:
Dr. O Ayten
Sultan Abdulhamid Han Teaching Hospital, Department of Pulmonary Medicine, Selimiye Street, Tibbiye Avenue, Uskudar, Istanbul
Turkey
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Source of Support: None, Conflict of Interest: None


DOI: 10.4103/njcp.njcp_614_19

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   Abstract 


Background: Postoperative bronchopleural fistula (BPF) remains a serious complication due to its high morbidity and mortality. Although various endoscopic techniques have been defined for the closure of BPF previously, no standard algorithm yet exists. Aims: To study the effectiveness and safety of various endoscopic procedures in an interventional pulmonology unit. Materials and Methods: The medical data of 15 postoperative BPF patients, who were undergone endoscopic intervention were retrospectively investigated. Results: The mean size of the fistulas determined by bronchoscopic evaluation was 7.93 ± 3.26 mm (range 3-15 mm). Applied procedures were as follows: stent implantation (n: 8, 53.3%), stent implantation and polidocanol application (n: 4, 26.7%), only Argon Plasma Coagulation (APC) application (n: 2,13.3%), polidocanol application (n: 1,6.7%). Complete fistula closure was achieved in three of the 15 patients (20%). The procedures were partly successful in five (33.3%) patients and failed to be successful in seven (46.6%) patients. Survival rates in regard to procedural success were determined and a statistically significant difference was found in five-year survival rates (P = 0.027, P < 0.05). Conclusion: Our results demonstrated that bronchoscopic procedures can be safely and effectively performed in patients who were not eligible for surgery for various reasons.

Keywords: Bronchopleural fistula, bronchoscopy, interventional pulmonology


How to cite this article:
Ayten O, Ozdemir C, Sokucu S N, Kocaturk C, Onur S T, Altin S, Dalar L. The role of interventional pulmonology for the postoperative bronchopleural fistula. Niger J Clin Pract 2021;24:633-9

How to cite this URL:
Ayten O, Ozdemir C, Sokucu S N, Kocaturk C, Onur S T, Altin S, Dalar L. The role of interventional pulmonology for the postoperative bronchopleural fistula. Niger J Clin Pract [serial online] 2021 [cited 2022 Dec 3];24:633-9. Available from: https://www.njcponline.com/text.asp?2021/24/5/633/316480




   Introduction Top


Bronchopleural fistula (BPF) is a communication between a main stem, lobar, or segmental bronchus and the pleural space.[1] BPF may be a complication of necrotizing pneumonia/empyema, lung malignity, or trauma, and also of some interventional procedures like thoracentesis, lung biopsy, chest tube drain, or radiotherapy. However, the most frequent reasons for BPF are surgical interventions like pneumonectomy and lobectomy.[2] Rates of BPF following pneumonectomy and lobectomy are 4.5%–20% and 0.5%, respectively.[3] BPFs can result in long-term hospital care and are associated with a significantly high mortality rate of 18% to 67%. The most frequent reasons for mortality in the BPFs are aspiration pneumonia and acute respiratory distress syndrome.[4]

The gold standard of BPF treatment is surgical repair; however, the control of infections, pleural drainage, nutritional support, and bronchoscopic interventions are also important adjuvant treatment components; various bronchoscopic methods have also been currently defined for the patients who are not suitable for surgery.[5],[6] In this study, we have discussed the effectivity and safety of these various endoscopic approaches in an interventional pulmonology unit.


   Materials and Methods Top


This retrospective study was performed in a tertiary hospital for chest diseases and thoracic surgery. The medical data of 15 patients who underwent bronchoscopic intervention for postoperative BPF between January 2009 and February 2015 was retrospectively investigated. The demographic properties of the patients, the etiology of the BPF, the size and localization of the fistula, and categories of the endoscopic interventions applied, and their success rates, were analyzed using the patients' medical records.

Description of the fistula

Diagnosis was confirmed with endoscopic evaluation when clinical, laboratory, and radiological signs lead to the suspicion of a postoperative BPF. Too small fistulas were diagnosed with presence of air bubbles after the administration of saline solution throughout the area of fistula. The size of the fistula was measured during endoscopic evaluation. BPFs that developed in the first 7 days after the operation were described as early, those in the 8th to 30th day as intermediate, and after 30 days as late period postoperative BPFs.

Flexible bronchoscopy (Olympus BF1T150, Tokyo, Japan) was performed for BPF diagnosis, for the evaluation of the treatment's effectiveness and during follow-ups, and flexible or rigid bronchoscopy (Efer Dumon Rigid bronchoscope, EFER Endoscopy, La, Ciotat, France) was applied for the closure of fistula, depending on the type of intervention.

Methods used in the closure of fistula

Submucosal polidocanol injections (Aethoxysklerol 2% Chemische Fabrik Kreussler & Co. Gmb H Wiesbaden, Germany) were applied all around the fistula stoma with an endoscopic needle and under the guidance of flexible bronchoscopy.

Argon plasma coagulation (APC) applications to the fistula stoma and stent insertions were performed via rigid bronchoscopy. Different types of stents were used like silicone Y type stent (Novatech, La Ciotat, France), tracheobronchial self-expanding conical nitinol stents (Tracheobronxane Silmet®xs, Novatech SA, France), and fully covered self-expanding metallic stents (Micro-Tech, Nanjing, China). The leg of the stent was cut accurately to cover the fistula area and was then closed with the bronchial stapler, and occluded. Our aim in this procedure was to cover the fistula stoma, to protect the contralateral lung against infections, to get rid of air leaks, and finally to secure closure of the stoma by the development of granulation tissue caused by the stent's abrasive effect on the mucosa.

All cases that underwent endoscopic intervention were high-risk patients for surgery, patients with poor general health, patients who had previous unsuccessful BPF closure, or patients who did not accept a surgical approach. The treatment was considered and decided by a multidisciplinary approach after BPF was confirmed.

Procedural efficacy was classified as completely successful, partly successful, and unsuccessful. Complete closure of the fistula was accepted as completely successful. Prevention of air leaks from the pleural drainage tube, decrease in the fistula size, gaining time for subsequent surgical treatment, and the control of pleural infections were accepted as partially successful, and failure of closure of fistula was accepted as unsuccessful.

Statistical analysis

The NCSS 2007 & PASS 2008 Statistical Software (Utah, USA) programs were used for statistical analysis. Descriptive data were expressed as the mean ± SD, median, frequency, ratio, minimum and maximum values. Nonnormally distributed parameters were compared between two groups using the Mann–Whitney U test. Qualitative data was compared using Fisher's Exact test and Fisher Freeman-Halton tests. Survivals were evaluated using the Kaplan Meier survival analysis; P values < 0.05 or < 0.01 were accepted as significant.


   Results Top


Demographic data, underlying diseases, and general characteristics of the patients are summarized in [Table 1]. BPF had developed between 4 and 90 days after surgery. One case had early period (6.67%), seven cases had intermediate period (46.67%), and seven cases had late period (46.67%) postoperative BPFs. The mean size of fistulas determined by bronchoscopy was 7.93 ± 3.26 mm (range: 3–15 mm).
Table 1: Properties of patients with postoperative BPF

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Three patients had previous unsuccessful surgical fistula repair. Remaining 12 patients were selected to undergo interventional bronchoscopic procedures after medical evaluation. All endoscopic interventions are given in [Table 2] and [Figure 1]a, [Figure 1]b. Complete fistula closure was achieved in three of the 15 patients (20%). Partial success was achieved in five patients (33.3%). In these cases, complete fistula closure was not achieved, but the prevention of air leaks from the pleural drainage tube, decrease in the size of fistula, time gaining for subsequent surgery, or control of pleuropleural infection were achieved. Interventional procedures were not successful in seven (46.6%) patients. There was no statistically significant difference between this unsuccessful group (n: 7) and other two partial/complete success groups (n: 8) in terms of side of operation, empyema existence, fistula size, rate of procedural complications, and type of operation (P > 0.05) [Table 3].
Table 2: Interventions applied in the patients and results of follow-ups

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Figure 1: (a) Bronchoscopic appearances of the fistula stoma. (b) Stapler covered silicone stent after inserted into the airway

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Table 3: Differences between groups with successful or unsuccessful interventional procedures

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In stent-implanted patients, the median follow-up period was 300.14 ± 412.53 days in the successful group and 22.60 ± 24.56 days in the unsuccessful group (P = 0.004). The duration of stent use increased the effectiveness of fistula closure for the patients where stents were inserted. There were no procedural complications in the patients who underwent APC and polidocanol applications. Any complications were not encountered in four of 12 patients who underwent stent implantation. In the remaining eight stent-implanted patients, various complications developed during their follow-up period. These were mucostasis (7 patients), development of granulation tissue (2 patients), and stent migration (1 patient). Repetitive bronchoscopic interventions had to be applied for the patients in which complications developed. The mean numbers of rigid and fiberoptic bronchoscopic instrumentations were 1.93 ± 1.28 and 2.73 ± 2.19, respectively. Procedure-related mortality was not seen.

Two patients from the unsuccessful intervention group and one case from the partially successful group were able to undergo surgical intervention, and the closure of the fistula was achieved in these patients.

The mean follow-up period of patients was 23.98 ± 19.67 months (range: 6 days–47.3 months). Within this period, two of the seven patients survived in unsuccessful group (28.6%); the mean survival time was found to be 14.11 ± 7.94 months. The last death existed in the 2nd month and the cumulative survival was 28.6%, with a standard deviation of 17.1%. Six of the eight cases survived (75%) in the successful group; the mean survival time was 38.08 ± 5.03 months. The last death existed in the 14th month, and the cumulative survival was 75.0%, with a standard deviation of 15.3%. When survival rates were evaluated with regard to procedural success by the Log Rank test, 4-year survival rates showed statistically significant differences (P = 0.027; P < 0.05); survival rates were higher in the successful group [Figure 2]. The causes of deaths during follow-up period were sepsis due to uncontrollable infection, hemoptysis, myocardial infarction, and metastatic disease.
Figure 2: Survival curve with regard to procedural success 28% Log-rank test 29%

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   Discussion Top


BPF is still a serious postoperative complication in thoracic surgery. In our study, we were able to demonstrate that interventional bronchoscopic procedures either single or in combination were an effective and safe treatment option in BPF management, especially in the patients for whom surgical repair could not be performed for various reasons, or surgical repair had not been successful.

There are various systemic and local factors that are responsible for BPF development after thoracic surgery.[7],[8],[9] In our study, the risk factors were diabetes mellitus, lung tuberculosis, and neoadjuvant chemotherapy. The risk of BPF development is noticeably higher after pneumonectomy than lobectomy. Moreover, right pneumonectomy is highly associated with BPF development.[9],[10] In our study, 66.7% of cases had a history of pneumonectomy and all was a right-sided operation.

Postoperative BPF development is most frequently observed in the first three months after the operation.[4],[11] Varoli et al. have classified postoperative fistula development as early (< 7 days), intermediate (8–30 days), and late (> 30 days).[12] According to this classification, most of our cases were intermediate and late period fistulas.

Bronchoscopy is the most important approach in the diagnosis of BPF and the determination of the fistula localization. Stoma of the fistula can be inspected under direct visualization. This also may help localizing the fistula and making the diagnosis by visualizing the air bubbles during bronchial lavage. Another method is to occlude the related subsegment with a balloon catheter, and to indicate the prevention of air leaks from the chest tube.[2]

The first step in BPF treatment is to prevent life-threatening tension pneumothorax and endobronchial contamination. Early pleural drainage, appropriate antimicrobial therapy, nutritional support, and immediate stump repair are other important steps of the treatment management. Various different surgical procedures are being applied for the repair of fistulas.[2],[13],[14]

Patients are very often considered unsuitable for surgery because of their poor general health. In such instances, bronchoscopic procedures are the only treatment options for BPFs.[3],[15] For this purpose, several bronchoscopic methods are described alone or in combination. Fibrin and acrylic adhesives, sclerosing agents, silicone or metallic stents, intrabronchial valves, and vascular coils, Nd: YAG, and argon plasma coagulation are some of these methods defined previously in the literature.[12],[16],[17],[18],[19],[20],[21] There is no consensus regarding which treatment is suitable and effective for each individual. Nonrandomized case series offers very variable results about the efficacy of these endoscopic interventions. Success rates in these nonhomogeneous case series have been reported to vary between 22.5% and 96.9% because of the differences in treatment strategies and case properties.[6],[22]

The size of fistula is also a matter of debate in the consideration of bronchoscopic interventions. It is claimed that bronchoscopic procedures are generally effective in fistulas less than 8 mm in size, and they should not be applied in fistulas greater than 8 mm (>8 mm).[6] In our study, the mean fistula size was determined to be 7.93 ± 3.26 mm (range: 3–15 mm); in seven cases, fistula size was larger than 8 mm. In our cohort, there was no difference in treatment success in regard to fistula size. We, therefore, suggest that endoscopic interventions can be successful in the cases that are not suitable for surgery, even if the size of fistula is large. In such cases, remodeled silicone stents may be the preferred option.

Studies investigating stent insertion in BPF treatment reported that stenting is an effective option. However, it must be emphasized that the patient groups are nonhomogeneous and the used stents had different properties. In a study by Andreetti et al., the complete closure of the fistulas was achieved in about 13 months by using conical self-expandable fully covered metallic stents in six patients. All fistulas were developed after pneumonectomies. No complications were observed during the follow-up periods, and the stents were removed.[23] In another study by Dutau et al., conical self-expandable metallic stents were used for large-sized fistulas (6–12 mm) in seven patients with BPF. In three of these seven cases, stent insertion gained time for subsequent surgery.[24] In a recent study of a total of nine patients, seven cases with varying fistula size (between 3.5 and 25 mm) were successfully treated with the application of fully covered self-expandable metallic stents. In these cases, air leaks from the drainage tube was stopped and 75% of the cases with empyema, treated with stent replacement.[25]

In our study, bronchoscopic interventions were found to be successful in 53.3% of the cases. Stent insertion was applied in 80% of the cases. The duration of the stent was longer in the cases in which stent insertion was successful. It is, therefore, possible to consider that it may be more effective to leave the stent longer when infection control is maintained and mucostasis is prevented. We consider that closure of Y stent's leg by stapler causes mucosal abrasion that stimulates granulation tissue formation, and eventually contributes to the closure of fistula, especially fistulas in main bronchus stumps.[16],[21],[22]

When stent insertion is the treatment of choice, the provision of an appropriate stent for the newly developing anatomical structure is the most important issue during applying stents into the airways. For this reason, we used silicone stents in the majority of patients. All stents were appropriately cut and remodeled according to the airway anatomy, and the parts covering the fistulas were occluded with the aid of a stapler. Abrasion effect, which was described above, is another factor for stent preference. Several complications were encountered in eight of the stent-inserted patients, including mucostasis, migration, and development of granulation tissue. Therefore, we concluded that these cases must be regularly followed-up, and appropriate interventions for such complications must be applied.

In a large series, including 35 patients with BPF, Varoli et al. reported complete fistula closure in 23 cases with submucosal injections of polidocanol, a sclerosing agent. The fistula sizes varied between 2 and 10 mm, and no complication was developed. In the remaining 12 cases with total dehiscence, polidocanol treatment failed.[12] In our study, we applied polidocanol in four patients in combination with stent insertion. All had small residual fistula after stent removal. Complete fistula closure was achieved in two of them. Polidocanol application combined with stent insertion is considered to be effective in the complete closure of the residual fistula area, following the removal of the stent.

BPF treatment with APC is reported in only one case in the literature.[21] In this case, two fistulas of 1 and 3 mm were determined in the operation stump, and the complete closure of the fistulas was achieved using APC application. In our study, one case of a 3 mm fistula was treated with APC, and the fistula stoma was completely closed. APC treatment may result in complete closure of the fistula stoma, especially in small-sized fistulas. The success rate of APC application may be increased by the elimination of secretions around the stoma, and by getting rid of the granulation tissue or tumoral infiltration in the operation stump.

In a current study, endoscopic treatment was applied to 35 of 52 cases with BPF, and success rate was found to be 80%.[22] The authors concluded that the appropriate selection of different endoscopic interventions used alone or in combination would help to reduce the need for further surgical interventions.

The retrospective property of our study and the smaller number of evaluated patients are the main limitations to be considered. Another limitation of our study is that we only evaluated endoscopic treatment patients and we did not have a control group. Endoscopic treatment procedures offer different methods, and they may be applied in combination.


   Conclusion Top


Postoperative BPF has to be treated using multidisciplinary approaches and decisions. In cases where surgical repair is unsuitable for various reasons, BPF can be treated by various endoscopic procedures alone or in combination. Bronchoscopic methods applied either alone or in combination were safe and effective in BPF treatment. They also associated with improved survival rates. Procedural success depends on effective infection control, the preference for a suitable stent for the anatomical structure, and regular follow-up. The selection and determination of the most appropriate treatment methods for individual BPF case require additional results from prospective randomized studies.

Financial support and sponsorship

Nil.

Conflicts of interest

There are no conflicts of interest.



 
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    Figures

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    Tables

  [Table 1], [Table 2], [Table 3]



 

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