The VALR™ surgical system (Spiration Inc, Redmond, WA) has been successfully tested in several small and large animal models of emphysema for lung volume reduction surgery (LVRS). However the size and anatomy of animal lungs is different than human, requiring analysis on ex-vivo human lungs with emphysema (EVHLE).
To evaluate the VALR system sleeve sizes in EVHLE and determine: the amount of tissue captured with a single sleeve, the effectiveness of sealing after tissue resection and safety.
Fifteen complete sets of fresh EVHLE were used in these experiments. The VALR surgical system uses controlled vacuum to capture lung tissue into a silicone sleeve. When deployed, the sleeve produces compression and sealing facilitating LVRS. Three different sleeve sizes (15, 17.5 and 20mm diameter) were tested on the upper lobes. After deployment, each sleeve was secured with suture, and then the tissue captured within the sleeve was resected leaving a small band of material compressing the lung. The volume of tissue captured was visually estimated compared to the entire lobe. The lungs were then inflated and tested for air leaks underwater. The tissue captured by the sleeve was weighed.
The average volume of upper lobe captured and reduced by the devices was 10-15, 25-30 and 35-40 percent by the 15, 17.5 and 20 mm sleeves, respectively. After tissue resection, no air leaks or tissue trauma were observed during lung inflation. By weight, 10±9, 30±7 and 41±10 grams of upper lobe were captured by the 15, 17.5 and 20 mm sleeves, respectively.CONCLUSIONS: In EVHLE, a single deployment of the VALR compression sleeves safely captured adequate amounts of tissue without apparent trauma or complications. There were no air leaks observed after tissue resection. A direct correlation was established between the size of the sleeve and the mass and volume of tissue reduced.
The VALR surgical system may be adequate for clinical use.
L.E. Snyder, Spiration Inc, Shareholder, Industry, discussion of product research or unlabeled uses of product.