Preliminary results of laser assisted sealing of hand sewn canine esophageal anastomoses

Dehiscence rates of esophageal anastomoses range between 5 and 20%1. Causative factors include ischemia, tension, foreign body reaction, microabscesses, and the negative pressure within the thoracic cavity. Laser assisted tissue sealing (LATS) has been shown to decrease anastomotic leakage rates in other tissues. Using a canine model we assessed the efficacy of LATS in enhancing single layer hand sewn intrathoracic esophageal anastomoses. Via a left thoracotomy, paired two centimeter transverse incisions (one laser sealed, one control) were made in the proximal and distal esophagus in nine dogs. Both were sewn using a single layer of 4-0 polyglycolic acid. A combination of albumin (0.2 cc), sodium hyaluronate (0.4 cc), and indocyanine green (1 gtt) was applied to one of the randomly chosen hand sewn repairs. The albumin/hyaluronate combination is used to provide a protein matrix across the anastomosis for ingrowth of fibroblasts. Indocyanine green dye selectively absorbs at approximately 805nm which matches the output of the diode laser (808 ± 1nm), thus improving uptake of laser energy by the targeted tissues. The anastomosis was then exposed to continuous wave diode laser energy for approximately 2 minutes at a power density of 9.6 W/cm². The esophagus was recovered either at the time of sealing or 2 days postoperatively and infused with saline under pressure. Bursting pressures were considered the point of initial saline leakage. At time 0 there was no significant difference in bursting pressures between the LATS group and controls. However, at 2 days postoperatively controls burst at 121 ± 14 mmHg while the laser assisted anastomoses burst at 295 ± 35 mmHg (p<.005). HPS staining of uninjured portions of the laser sealed anastomoses revealed minimal thermal injury to the mucosal surface initially, with some regeneration of mucosal lining at 2 days postoperatively. No foreign body reaction to the solder was noted. Laser reinforcement of single layer hand sewn esophageal anastomoses appears to increase bursting pressure and may result in reduced incidence of anastomotic leakage.