Departments: Interventional Pulmonology in Other Journals
Bronchoscopic Volume Reduction with Valve Implants in Patients with Severe Emphysema
Lancet. 2003;361:931–933. Toma TP, Hopkinson NS, Hillier J, Hansell DM, Morgan C, Goldstraw PG, Polkey MI, Geddes DM. Department of Thoracic Medicine, National Heart and Lung Institute, and Department of Respiratory Medicine, Department of Radiology, Department of Anesthesia, and Department of Thoracic Surgery, Royal Brompton Hospital, London.
This report reports the results of a pilot study of unilateral volume reduction by endobronchial valve insertion (EVI) in 8 patients with severe emphysema. All patients had severe dyspnea on exertion despite medical treatment, including 6 weeks of pulmonary rehabilitation. Five of these had emphysema judged too severe for lung volume reduction surgery (LVRS) and 3 had refused LVRS. The distribution of emphysema was heterogeneous, as demonstrated by high-resolution computed tomography and ventilation/perfusion scintigraphy. The target upper lobe was chosen based on high-resolution computed tomography and ventilation/perfusion lung scan. The patients included 1 woman and 7 men with a median age of 59 years (range, 43–69 y). The endobronchial valves were placed in all segmental bronchi leading to the upper lobe that was most affected by emphysematous destruction. The endobronchial valve is a stent-supported one-way valve made of silicon and nitinol that prevents air entering the target lung but allows air and mucus to exit. The valves and delivery catheters were inserted with a flexible bronchoscope and a guidewire. If necessary, the valves could be removed bronchoscopically with grasping forceps. All procedures were done under an intravenous anesthetic regimen based on propofol and remifentanil. Four patients had valves placed in the right upper lobe, 2 in the left upper lobe and 2 in the left upper lobe and the lingula. The 25 valves were placed without any technical difficulty and the median time for the procedure was 1 hour (range, 0.5–2.5 h). All patients were extubated without difficulty and patients stayed an average of 2 hours in the surgical recovery room before transfer to the surgical general ward. Patients then remained in hospital for up to 10 days for observation and follow-up tests. Bronchoscopy was repeated 4 weeks after the procedure to inspect the valve implant site. The patients were assessed before, then 1 week and 4 weeks after EVI. After EVI, the median FEV1 increased from 0.79 L (range, 0.61–1.07 L) to 1.06 L (0.75–1.22 L) (difference 34%, P = 0.028) and the median diffusing capacity (TLCO) increased from 3.05 mL/min/mm Hg (2.35–4.71) to 3.92 mL/min/mm Hg (2.89–5.40) (difference 29%, P = 0.017). Computed tomography scans demonstrated a substantial reduction in regional volume in 4 of the 8 patients. Two patients developed a transient pneumothorax (one requiring drainage), but no other important adverse effects were noted during follow up. Based on these results, the authors conclude that lung-volume reduction can be achieved with unilateral bronchoscopically placed valve implants in patients with severe emphysema with acceptable short-term safety and worthwhile functional benefits. The bronchoscopic volume reduction described here requires a large-scale study with a substantial number of patients before widespread clinical use of this technique is recommended. More importantly, the long-term complications of the iatrogenic endobronchial foreign body need careful assessment. The potential complications include post-obstructive pneumonia and abscess, bronchiectasis, formation of granulation tissue, migration of the endobronchial valve into other bronchi or into lung parenchyma, bronchial tear, bronchial hemorrhage, pneumothorax, and chronic cough. Earlier studies have shown that a bronchoscopically applied fibrin-glue preparation could help affect lung volume reduction (Am J Respir Crit Care Med. 2001;164:295–301). The long-term results of any type of bronchoscopic lung volume reduction procedure remain to be seen. The bronchoscopic “resizing” of the overexpanded lung has the potential to become a common procedure. However, we must design a suitable technique to accomplish this.