Efficacy of polyglycolic acid sheets and fibrin glue for the prevention of post-ELPS bleeding.

OBJECTIVE: To assess the efficacy and safety of a covering method using polyglycolic acid (PGA) sheets and fibrin glue in preventing laryngopharyngeal bleeding after endoscopic laryngopharyngeal surgery (ELPS) combined with endoscopic submucosal dissection (ESD). METHODS: Twenty-one patients who underwent ELPS combined with ESD (28 resected pharyngeal carcinomas) were retrospectively evaluated. After completing ELPS combined with ESD, fibrinogen was sprayed onto the ulcer. A PGA sheet cut into 5 × 5 mm pieces that fit the size of the ELPS-induced ulcer was then placed over the ulcer and fixed in place with a fibrin glue comprising thrombin. RESULTS: The resection procedure was performed for all lesions. The median long diameter of the resected specimen was 36 mm. The rate of a resected specimen diameter >30 mm, use of anticoagulant/platelet, and macroscopic classification 0-Ⅱa were 68% (19/28), 19% (5/28), and 36% (10/28), respectively. The median time required to cover ELPS-induced ulcers using PGA sheets and fibrin glue was 10 min (range: 3-22 min). No post-ELPS bleeding, subcutaneous emphysema, or aspiration pneumonia (0/28) was observed. CONCLUSION: The covering method using PGA sheets and fibrin glue for ELPS-induced ulcers is considered to be sufficiently safe and effective in preventing post-ELPS laryngopharyngeal bleeding. This method could be useful in preventing post-ELPS bleeding in patients with head and neck cancer.

Au(I)-Catalyzed cycloisomerizations terminated by sp(3) C-H bond insertion.

The gold(I)-catalyzed cycloisomerization of 1,5-enynes and 1,4-allylallenes to tetracyclododecane and tetracyclotridecane derivatives, respectively, is reported. Complexation of the cationic gold(I) complex to either the alkyne or allene moiety induces an intramolecular addition of the alkene, leading to a gold(I)-stabilized carbenoid intermediate. This intermediate undergoes a formal sp(3) C-H insertion to generate the tetracyclic adduct. A series of deuterium labeling experiments showed that the C-H functionalization step proceeds with an inverse kinetic isotope effect.