Biodegradable Airway Stent Post Lung Transplant

Study Overview
=================
Brief Summary
-----------------
Introduction and rationale Benign airway stenosis or malacia is a frequent complication of lung transplantation occurring in 4-24% of patients, most often occurring two to nine months post-transplant. Initial therapeutic approach consists of conservative endobronchial treatment with recurrent balloon dilatation, radial incision, and electro cautery. For severe case of recurrent stenosis or malacia, airway stent placement can be considered. Different types of airway stent exist, for instance self-extendable metallic stent (SEMS), silicone stent and biodegradable airway stent. Conventional airway stents (SEMS, silicone) are associated with complications as granulation tissue and recurrent infections and can be difficult to remove. Newly developed biodegrabale stents are made of polydioxanone and disintegrate after a period of time are thought to have less side effects, and has been standard of care for the last few years. A sub selection of patients have been treated with conventional stent before treated with biodegradable stent. Research question To assess the efficacy and efficiency of biodegradable airway stent. Compare occurrence of adverse events such as infection, dislocation, in stent granulation and difficulty of removal to conventional metallic or silicone stents. Asses if biodegradable stent lead to improvement of lung function. Assessment of the life span of biodegradable stents.

Detailed Description
-----------------
Background Recurrent airway stenosis or malacia can be treated with airway stents. Conventional airway stents, for instance self-extendable metallic stent (SEMS) and silicone stent are associated with adverse events as recurrent infection or granulation tissue and can be difficult to remove because of in stent-granulation. Therefore they are used with restraint for benign airway problems. Biodegradable stents are made of polydioxanone and disintegrate after a period of time. They are thought to be well tolerated and associated with less adverse events compared to traditional airway stent and have been used as standard care for multiple years. Main research question To assess the efficacy and efficiency of biodegradable airway stent Compare occurrence of adverse events such as infection, dislocation, in stent granulation and difficulty of removal to conventional metallic or silicone stents. Asses if biodegradable stent lead to improvement of lung function. Assessment of the life span of biodegradable stents. Design (including population, confounders/outcomes) Retrospective cohort study of patients with airway stenosis or malacia treated with biodegradable airway stent from 2019 in the UMCG and Amsterdam UMC. Expected results Less adverse events, hospital admittance and need for bronchoscopic interventions compared to patients treated with conventional stents. No complications associated with removal of stents. Life span around 4 months

Official Title
-----------------
Evaluation of Treatment With Biodegradable Airway Stent for Post Lung Transplant Airway Complication

Conditions
-----------------
Airway Complications Post Lung Transplant

Intervention / Treatment
-----------------
* Device: Biodegradable stent


Participation Criteria
=================
Eligibility Criteria
-----------------
Inclusion Criteria: Patients who underwent a lung transplantation and developed airway stenosis or malacia with airway stent requirement Exclusion Criteria: No

Ages Eligible for Study
-----------------
Minimum Age: 18 Years

Sexes Eligible for Study
-----------------
All

Accepts Healthy Volunteers
-----------------
No

Study Plan
=================
How is the study designed?
-----------------

Design Details

Primary Purpose: Treatment
Intervention Model: Single Group Assignment
Masking: None (Open Label)


Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Experimental: Biodegradable stent treatment group<br>Biodegradable stent treatment group | Device: Biodegradable stent<br>* Bronchoscopic placement of biodegradable stent in patients with airway complications after lung transplant<br>|

What is the study measuring?
-----------------
Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Adverse events | Adverse events associated with airway stents | 4 months after placement | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Change in FEV1 | Change in FEV1 measured by spirometry pre and post stent placement | 1 week post placement | 
| Change in FVC | Change in FVC measured by spirometry pre and post stent placement | 1 week post placement | 
| Time to need for new stent placement | Endurance and life span of biodegradable stent measured by time to need for new stent placement | 6 months after placement |