The effect of cartilaginous reinforcing sutures on initial tracheal anastomotic strength: a cadaver study.

OBJECTIVE: During tracheal resection with primary anastomosis, cartilaginous reinforcing sutures may be placed outside of the primary anastomosis with the goal of preventing early dehiscence. The direct effect of such reinforcing sutures on anastomotic strength has not been previously investigated. The goal of this study was to determine if the addition of cartilaginous reinforcing sutures adds to tracheal anastomosis stability. STUDY DESIGN: Prospective cadaver study. SETTING: This research was conducted at an anatomy lab at Indiana University School of Medicine. SUBJECTS AND METHODS: Twelve cadaver tracheas were harvested. Each trachea was bifurcated, with 1 segment of each trachea transected and anastomosed using circumferential sutures and the remaining tracheal segment undergoing the same procedure with the addition of cartilaginous reinforcing sutures. Segments (proximal versus distal) were alternated to control for potential anatomic-based strength differences. The force necessary for anastomotic rupture was measured, and a Wilcoxon signed-rank test was used to compare means. RESULTS: Analysis demonstrated the mean anastomotic rupture point for tracheas with reinforcing sutures was 297 N (95% confidence interval = 241.1-352.9), while the mean for trials without reinforcing sutures was 173 N (95% confidence interval = 142.63-203.37; P = .0054). The point of rupture occurred at the anastomosis in 1 case with reinforcing sutures and in 8 of 11 cases without reinforcing sutures. CONCLUSIONS: Cartilaginous reinforcing sutures were found to provide a higher force requirement for tracheal anastomotic rupture when compared with anastomoses without these sutures. This improved stability in tracheal anastomosis may result in a decreased risk of early tracheal rupture after anastomosis.

An experimental model to investigate initial tracheal anastomosis strength.

OBJECTIVES/HYPOTHESIS: Early anastomotic dehiscence is a devastating complication of segmental tracheal resection. Although wound healing, patient comorbidities, and anastomotic tension are all influential factors, there is a paucity of information available on initial tracheal stability after various tracheal anastomosis techniques in human tissue. STUDY DESIGN: Prospective cadaver study. METHODS: We present a novel, inexpensive pulley-based system to apply symmetric tension on the trachea in a longitudinal direction to the point of anastomotic dehiscence. The validity of this mechanism was confirmed with trials using incrementally increasing quantities of the same suture type. Twenty-four trials were then performed on 12 cadaver tracheas (six fresh and six preserved) to compare anastomotic strength with two commonly used suture materials (3-0 polyglactin [Vicryl] vs. 3-0 polydioxanone [PDS]). RESULTS: Validation studies demonstrated that the force increased appropriately with an increasing number of sutures tested. In the tracheal anastomoses, tracheal suture pull-through was the most common mechanism of dehiscence, regardless of suture type. No significant difference in anastomotic stability was detected between the fresh versus preserved cadaver tracheas. The mean anastomotic strength was slightly greater for Vicryl (179.9 N) when compared to PDS (161.5 N), but the difference did not reach significance (P = .207). CONCLUSIONS: We introduce an inexpensive tool for measuring initial tracheal anastomosis stability with human cadavers, which demonstrated no difference in the tracheal pull-through strength of Vicryl and PDS.