An outcome analysis of self-expandable metallic stents in central airway obstruction: a cohort study

Abstract

BackgroundSelf-expandable metallic stents (SEMSs) have provided satisfactory management of central airway obstruction. However, the long-term benefits and complications of this management modality in patients with benign and malignant obstructing lesions after SEMS placement are unclear. We performed this cohort study to analyze the outcomes of Ultraflex SEMSs in patients with tracheobronchial diseases.MethodsOf 149 patients, 72 with benign and 77 with malignant tracheobronchial disease received 211 SEMSs (benign, 116; malignant, 95) and were retrospectively reviewed in a tertiary hospital.ResultsThe baseline characteristics of patients who received SEMS implantation for benign conditions and those who underwent implantation for malignant conditions were significantly different. These characteristics included age (mean, 63.9 vs. 58; p < 0.01), gender (male, 62% vs. 90%; p < 0.0001), smoking (47% vs. 85%; p < 0.0001), forced expiratory volume in 1 second (mean, 0.9 vs. 1.47 L/s; p < 0.0001), follow-up days after SEMS implantation (median; 429 vs. 57; p < 0.0001), and use of covered SEMS (36.2% vs. 94.7%; p < 0.0001). Symptoms improved more after SEMS implantation in patients with benign conditions than in those with malignant conditions (76.7% vs. 51.6%; p < 0.0001). The overall complication rate after SEMS implantation in patients with benign conditions was higher than that in patients with malignancy (42.2% vs. 21.1%; p = 0.001). Successful management of SEMS migration, granulation tissue formation, and SEMS fracture occurred in 100%, 81.25%, and 85% of patients, respectively.ConclusionsPatients who received SEMS implantation owing to benign conditions had worse lung function and were older than those who received SEMS for malignancies. There was higher complication rate in patients with benign conditions after a longer follow-up period owing to the nature of the underlying diseases.

Complications Following Therapeutic Bronchoscopy for Malignant Central Airway Obstruction

“…1,2,4,5,16,18,[26][27][28][29][30] We focused solely on patients with malignant central airway obstruction because prior work has shown that the magnitude of the eff ect of risk factors varies based on whether the patient has malignant or benign disease. 1 Many previous studies reporting risk factors for therapeutic bronchoscopy failed to make this distinction.…”

“…Prior studies of therapeutic bronchoscopy for central airway obstruction [2][3][4][5][6][7][8][9][10][11][12] have included both malignant and benign cases, and most were done retrospectively, although some have focused on malignant disease. [13][14][15][16][17][18] Reported complication rates are low, but complications and outcomes diff er signifi cantly depending on the indication for the procedure (ie, malignant vs benign disease, isolated hemoptysis vs central airway obstruction), and in most studies, signifi cant heterogeneity existed in terms of patient population and indications.…”

“…[13][14][15][16][17][18] Reported complication rates are low, but complications and outcomes diff er signifi cantly depending on the indication for the procedure (ie, malignant vs benign disease, isolated hemoptysis vs central airway obstruction), and in most studies, signifi cant heterogeneity existed in terms of patient population and indications. 1,4 Many of these studies focused on individual technologies, such as stents, microdebriders, or APC, and most were performed at centers of excellence as part of ongoing research programs. Whether variations in practice patterns aff ect complication rates is unknown and cannot be answered by single-center studies.…”

Stents Are Associated With Increased Risk of Respiratory Infections in Patients Undergoing Airway Interventions for Malignant Airways Disease

“…Most other studies of infection in patients undergoing therapeutic bronchoscopy have used incidence proportions. [3][4][5][6][7][8][12][13][14] As we have shown in our previous work, incidence proportions have signifi cant limitations when used to analyze long-term complications; the incidence rate is a more appropriate measurement because it measures events per persontime at risk. 9 An additional benefi t of using survival analysis methods with time-varying covariates is that we can control for factors that vary over time, such as the degree of airway obstruction and stent removal.…”

“…We classifi ed respiratory infections using a method similar to those of previously published studies. [3][4][5][6][7][8] We defi ned a lower respiratory tract infection as present on the basis of clinical fi ndings of fever, purulent sputum, and worsening cough, with or without radiographic evidence of pneumonia. We also required that there be documentation by the managing physician of a clinical diagnosis of lower respiratory tract infection and that antibiotics be prescribed for it.…”