Clinical Analysis Of Bronchoscopic Interventional Therapy In The Treatment Of Central Airway Obstruction Following Lung Transplantation

ObjectiveTo analyze the clinical features of patients with central airway obstruction following lung transplantation and to assess the efficacy and safety of bronchoscopic interventional therapy on central airway obstruction by retrospective study.MethodsFrom January 2011 to December 2016,the clinical data of 26 patients with central airway obstruction following lung transplantation in the bronchoscopy center of Shanghai Changhai Hospital were retrospectively investigated.The initial treatment of stenosis involved balloon dilatation alone or combined with cryotherapy,laser,or self-expanding metallic stent.The symptoms of airway obstruction,stenosis diameter and FEV₁ were observed before and after each treatment of balloon dilatation and metallic stent placement to evaluate the immediate effect.The stenosis diameter,dyspnea index,FEV₁,6MWD and BODE index before and after treatment were evaluated to assess the comprehensive efficacy.The number of interventions in a follow up of six months were analyzed to evaluate long-term effect.Complications of different interventional bronchoscopic techniques were evaluated to assess the safety.Results1.General features:26 patients with central airway obstruction following lung t ransplantation received bronchoscopic interventional therapy in our bronchoscopy center of Shanghai Changhai Hospital from January 2011 to December 2016.The cases of the male and female were 16 and 10 respectively with a mean age of?47±15?fro m 14 to 70 years old.Primary indications for transplant:COPD?n=8?,IPF?n=8?,IP AH?n=5?,obliterans bronchiolitis after bone marrow transplantation?n=2?,bronchiecta sis?n=1?,cystic fibrosis?n=1?,lymphangioleiomyomatosis?n=1?.There were 15 bilater al lung transplant recipients and 11 single lung transplant recipients?Left 6,Right5?.The end-to-end anastomosis were utilized.2.Endoscopic description:extent of abnormalities in regard to the anastomosis:a?n=10?,b?n=5?,c?n=8?,d?n=3?.Before treatment,Macroscopic aspect:M₀?n=5?,M₂?n=14?,M₃?n=7?.Diameter:D₂?n=8?,D₃?n=18?.Sutures:S₀?n=26?.The severity of bronchial ischemia:Grade I?n=19?,Grade II?n=6?,Grade III?n=1?.After treatment,macroscopic aspect:M₀?n=11?,M₂?n=13?,M₃?n=2?.Diameter:D₂?n=17?,D₃?n=9?.Sutures:S₀?n=26?.The severity of bronchial ischemia:Grade I?n=24?,Grade II?n=2?.3.Interventional bronchoscopic techniques:as the basic treatment,balloon dilatation was performed alone in 6 cases?23.1%?and combined with cryotherapy or laser in 20cases?76.9%?.7 cases?26.9%?of refractory stenosis received stent insertion with a time from 28 to 67 days.227 procedures were performed including:157 balloon dilatations,34cryotherapies,22 lasers,7 stent insertions and extractions.4.The immediate efficacy:136?86.6%?in 157 balloon dilatations received immediate efficacy with improvement of symptoms.All the 7 cases?100%?of refractory stenosis got immediate efficacy after stent insertion with FEV₁ improved from?1.20±0.24?L to?1.71±0.20?L and increased 45%averagely.5.The improvement of stenosis diameter,dyspnea index,FEV₁ and 6MWD after treatment:stenosis diameter,dyspnea index,FEV1 and 6MWD were evaluated before and after bronchoscopic interventional therapy.The mean stenosis diameter was increased from2.5?1.0?mm to 7.0?2.0?mm.Dyspnea index was reduced from 3.0?1.0?to 2.0?1.3?.FEV1 was increased from?1.41±0.28?L to?1.73±0.30?L.6MWD was improved from?316.50±69.04?m to?368.65±57.38?m.BODE index was reduced from?4.65±1.77?to?3.08±1.62?.The improvement of stenosis diameter,dyspnea index,FEV₁ and 6MWD after treatment had significant difference.6.The long term efficacy:excluding 2 patients died of lung infection,24 patients accomplished the follow up of 6 months after treatment.The occurrence of restenosis varied individually.6 cases?25.0%?were absent of interventional procedures,11 cases?45.8%?received 1 or 2 procedures,and 7 cases?29.2%?received more than 3 procedures to keep airway clear.For 6 cases who received stent insertion,the total number of procedures in 6 months before insertion and after extraction was 33 vs 10 respectively with a decrease of 23.7.The complications of balloon dilatation were slight and easily managed including:retrosternal pain?n=62?,transient hypoxemia?n=48?,mucosa's membrane bleeding?n=22?.2 cases of transient hypoxemia in lasers recovered after simple processing.No complications occurred during cryotherapies and stent insertions.Complications of stent placement included granulation tissue formation?n=3?and tissue necrosis?n=1?.Mucosa's membrane bleeding during extractions was stopped after local perfusion of thrombin.Conclusion1.Balloon bronchoplasty through flexural bronchoscopy has immediate curative effect in the treatment of central airway obstruction following lung transplantation with excellent usability and safety.Balloon dilatation alone or combined with cryotherapy,laser,and self-expanding metallic stent,can keep airway clear and improve the symptoms of shortness,lung function,and exercise endurance.A part of patients can achieve a stable long-term effect. Balloon dilatation is also effective for most restenosis.Balloon bronchoplasty should be the initial and basic interventional therapy for central airway obstruction following lung transplantation.2.For severe bronchial stenosis refractory to balloon bronchoplasty,temporary metal stent can be used for selective patients and have an ideal immediate efficacy while helpful for long-term stability of airway to reduce long-term intervention.Short term applications of metal stent still have a risk of severe complications and should be closely followed up.