The Journal of Thoracic and Cardiovascular Surgery, Vol 103, 781-783, Copyright © 1992 by The American Association for Thoracic Surgery and The Western Thoracic Surgical Association
Laser activation of tissue sealant in hand-sewn canine esophageal closure
JS Auteri, MC Oz, V Jeevanandam, JA Sanchez, MR Treat and CR Smith
Department of Surgery, Columbia-Presbyterian Medical Center, New York, N.Y. 10032.
Dehiscence rates of esophageal anastomoses are between 5% and 20%. Because
small leaks between sutures might promote microabscess formation and lead
to dehiscence, we postulated that a better initial physical seal might be
beneficial. Reinforcement with laser activation of tissue sealant (LATS) is
a new technique that has been shown to increase the bursting strength of
anastomoses in other tissues. The tissue sealant is composed of 0.4 ml of
hyaluronic acid and 0.2 ml of albumin, to which 3 drops of indocyanine
green dye are added to give the sealant a peak absorbance of 805 nm,
matching the wavelength (808 nm) of a small, hand-held diode laser. Since
tissues do not absorb at this wavelength, laser energy is focused in the
sealant, minimizing collateral thermal damage. To extend this concept, we
assessed LATS in a canine model of esophageal closure. The esophagus was
exposed via a right thoracotomy in 20 dogs, and two transverse incisions, 2
cm in length, were made in each esophagus (n = 40 closures). Both sites
were closed with a single layer of interrupted 4-0 polyglycolic acid
suture. Either the proximal or distal incision was randomly chosen to
receive laser activation of tissue sealant. Tissue sealant was applied to
the reapproximated edges of the hand-sewn closure, which was then exposed
to diode laser energy. The end point was visible shrinking and desiccation
of the sealant, which required about 2 minutes. Each esophagus was
recovered at 0, 2, or 7 days postoperatively (n = 10, 5, and 5 dogs,
respectively), bursting pressure was measured, and the closures were
examined histologically. At all three time points LATS closures had
significantly higher bursting pressures than control closures (time 0: 251
+/- 87 versus 105 +/- 46, p less than 0.0001; time 2 days: 296 +/- 36
versus 121 +/- 14, p less than 0.0013; time 7 days: 318 +/- 72 versus 197
+/- 60, p less than 0.0021). Histologic study revealed trace thermal
injury, with regeneration of intact mucosal lining by 7 days. Conclusion:
laser activation of tissue sealant is a simple technique that significantly
increases the strength of esophageal closure and may reduce the prevalence
of dehiscence.
