Laser-Assisted Anastomoses of the Trachea and Carotid Artery in Dogs

Abstract

Anastomoses or reconstructions at the trachea are known to be related to a high risk of complications. Simi larly, anastomoses at smaller vessels have often occasioned discussion con cerning new techniques and different suturing materials. Low-dose laser energy seems to offer a new chance of tissue welding in these areas. In 10 Beagle dogs tracheal anastomoses were performed with an argon laser system, stabilized only by three single sutures for readaptation of the stumps. In 5 dogs even these three su tures were removed immediately af ter the tissue welding was finished. The anastomoses were monitored by bronchoscopy after an interval of six weeks and were removed after twelve weeks for pathologic investigations. In another 5 dogs carotid arteries were transected and reanastomosed with a similar technique. Readapta tion was achieved by four single su tures at equal distance, which were left in situ. Patency was monitored by Doppler ultrasound and by angiogra phy, and again after an interval of four to six weeks the anastomotic seg ments were resected and examined pathologically. All animals showed an uneventful postoperative course. None of the tracheal anastomoses showed any signs of functional impairment, air leakage, or infection. Bronchoscopy revealed no significant luminal nar rowing. These findings were con firmed after resection. Histology showed regular wound healing and especially normal reconstruction of the ciliated endothelium of the tra chea. Similarly all carotid anasto moses were patent in Doppler ultrasound and angiographic con trols. Neither angiography nor direct inspection after resection revealed signs of aneurysm formation. Micro scopic investigations showed a smooth endothelial passage between the two anastomosed segments and regular wound healing of the arterial wall. There were no signs of excessive scar formation or intimal hyperpla sia. The results underline the applica bility of laser energy for the perform ance of anastomoses at the tracheobronchial tree, as well as at smaller vessels. Clinical application has to be preceded by further investi gations and some technical improve ments, but still the technique shall prove to be an alternative to conven tional suturing techniques for se lected cases in the near future.