Effect of age on resistance to distraction after tracheal anastomoses with two suture patterns in cats

Abstract

Objectives: The aim of the study was to assess the effect of age on the ability of tracheal anastomoses in 24 feline cadaveric tracheae that were performed with two suture patterns to sustain distraction. Methods: Tracheae were obtained from 16 immature and eight adult cats and were divided into three groups. Each trachea underwent end-to-end annular ligament anastomosis using a simple continuous pattern with a 4/0 polypropylene suture on a round-body needle. In one immature group, three additional simple interrupted tension-relieving sutures were placed. The samples were tested with a tensiometer set at a drop head speed of 50 mm/min, and failure during distraction was defined by tissue pull-through or suture material failure. The force and elongation at failure were compared among groups. Results: Tracheal anastomoses in immature cats failed at lower mean forces (11.49 ± 1.30 N) compared with those with tension-relieving sutures and with adult cats (19.74 ± 4.55 N and 18.02 ± 1.28 N, respectively) (P <0.001). Tracheae from both immature groups sustained greater mean elongation (46.60 ± 0.06% and 46.53 ± 0.06%) compared with those from the adult group (33.85 ± 0.11%) (P = 0.017 and 0.09, respectively). Conclusions and relevance: Tracheal anastomoses with tension-relieving sutures in immature cats and anastomoses in adult cats showed greater resistance compared with immature cats without tension-relieving sutures. Tracheae from immature cats showed greater elasticity compared with adult cats. Immature cats may resist longer tracheal resection than adult cats, but reinforcement techniques are necessary to improve resistance to tension.