Pullout Strength for Three Suture Patterns Used for Canine Tracheal Anastomosis

Objective— To compare pullout strength of 3 suture patterns used for canine tracheal anastomosis. Study Design— Experimental study. Sample Population— Cadaveric canine tracheae (n=20). Method— Tracheal segments were anastomosed with 1 of 3 suture patterns: simple continuous, simple interrupted, and simple interrupted reinforced with horizontal mattress, each encircling annular cartilage rings adjacent to the transection site. Horizontal mattress sutures encircled the annular rings proximal and distal to the rings closest to the anastomosis. Each construct was distracted (0.5 mm/s) in a materials testing machine to failure. Load–displacement curves were generated and failure load (pullout strength) determined and mode of failure recorded. Results— Tracheal anastomosis with a simple interrupted pattern was significantly weaker (mean±SD pullout strength, 102.55±30.14 N) than simple continuous (135.53±15.47 N) or simple interrupted plus horizontal mattress (132.39±21.46 N), which were not different from each other. Mode of failure was consistently by suture tear out. Conclusions— Both simple continuous and simple interrupted reinforced with horizontal mattress suture patterns have significant biomechanical advantage over a simple interrupted pattern alone in canine cadaveric tracheal anastomosis. The simple continuous pattern had the least variability in pullout strength. Clinical Relevance— A simple continuous technique should be considered when selecting a tension‐relieving pattern for canine tracheal anastomosis. It offers the same biomechanical advantage as a simple interrupted pattern reinforced with a horizontal mattress pattern and its strength appears to be reliably maintained when tested in canine cadaver tracheae.