Breaking strength of native and sutured trachea - An experimental study onsheep trachea

Tracheal anastomoses are, even more so than other sutures, often only possi ble to prepare under tension and thus in danger of breakage. No information is available regarding native tracheae and freshly sutured tracheae. For t his reason, our objective was to examine the tensile strength of native tra cheae and compare it with freshly sutured specimens. Fresh tracheae were co llected from the local slaughterhouse within 30 min of slaughter. With the help of a suitable holding device, 24 fresh tracheae were mounted on a mate rial testing machine and stretched to breaking point, during which the forc e and distance required were recorded. The same study was carried out on ea ch 10 freshly anastomosed tracheae using three different suturing technique s. The mean value of the maximum force required for native tracheae was 198 N. With continuous suturing (polypropylene), a mean value of 171 N was att ained, and with single interrupted suturing (polydioxanone and polyglactin 910), 123 N, respectively, 108 N. Differences between the groups proved to be highly significant. With respect to the mechanical strain from traction, the continuous suture proved to be statistically identical to native trach eae, whereas single interrupted sutures revealed a considerably lower stabi lity under burden. Therefore, the continuous suture is of advantage in resp ect of the mechanical strain from traction and the suture protection of tra cheal anastomoses. Further studies with differing survival times in vivo wi th this method provide insight into the stability of tracheal anastomoses d uring the healing process. Copyright (C) 2001 S. Karger AG, Basel.