Though the NETT study has identified groups of emphysema patients who could benefit from surgical volume reduction it is not always easy to decide whether an individual patient should be operated. In search of a predictive test, we used a temporary endoscopic blockade of segmental bronchi to mimic the post-surgical condition.
21 patients with heterogenous lung emphysema, 15 male, 6 female, mean age 56 years were included in this IRB approved study. CT scans and perfusion scans were used to identify target zones for surgery. Patients underwent flexible bronchoscopy under local anesthesia. The bronchi supplying the potential surgical target segments were isolated with a sheath catheter. Controlled aspiration was used to create volume reduction of the emphysematous areas. Following this aspiration phase, the segmental bronchi were blocked with reversible devices. For the first nine patients we used bronchus blocking balloon-catheters (Rüsch, Kernen, Germany), in the last 12 patients dedicated occlusal stents (Pulmonx Inc., Palo Alto, USA) were implanted through the working channel of the bronchoscope. Between two and eight segmental occlusal stents were used per patient. Within 96 hours after treatment, chest CTs, perfusion scans, and function tests were repeated before the blocking devices were removed with flexible bronchoscopy.
None of the patients deteriorated. One patient developed a pneumothorax, two patients had elevated temperatures without radiological signs of pneumonia. No typical atelectases were seen in post-procedure CTs. However, body-plethysmography revealed losses of volume. In most patients improvement of pulmonary function was found within the short observation period. On average, TLC dropped from 7.4 to 7.1 l, ITGV from 5.7 to 5.1, VC increased from 2.5 to 2.8 l, FeV1 from 0.9 to 1.1 l. In 19 of the 21 patients exercise capacity improved. Seven good responders were operated.
Endoscopic volume reduction is practical, well tolerated, effective and relatively safe.
Encouraged by the good results we are now carrying out a chronic study, assessing the therapeutic use of occlusive stents.
L. Freitag, Pulmonx Inc.