Pure transvesical NOTES appendectomy using a 5-mm rigid laparoscope: a feasibility and survival study with porcine models.

BACKGROUND: Previously, the authors demonstrated the feasibility of a pure transvesical natural orifice translumenal endoscopic surgery (NOTES) for uterine horn resection (UHR) using a rigid ureteroscope in swine as an appendectomy model. However, visualization was poor, and there was room for improvement. The authors have assessed the feasibility and safety of a revised technique that uses a 5-mm rigid laparoscope.
METHODS: Eight operations on four female pigs (35-40 kg) were performed as a proof of concept study. Four right-side operations were performed in a survival model. The surgical procedure was similar to the original technique. However, the rigid ureteroscope was replaced by a 5-mm laparoscope after modification of the access system. In addition, the clipped metal threads used for bladder closure were easily placed with a long 13-gauge needle. In the survival model, a Foley catheter was placed for 1 day.
RESULTS: The new technique provided considerably better visualization and operability than the original technique. The mean total operative time was 96.6 ± 18.2 min, and the mean estimated blood loss was 15.0 ± 13.5 ml. On postoperative day 3, pig 2 in the survival study died of peritonitis resulting from a small bowel injury. The lab results for the other pigs demonstrated no adverse events and tolerable immune responses. Necropsy showed complete healing of the vesicotomy.
CONCLUSIONS: The revised transvesical NOTES UHR technique improved the outcomes and feasibility of the original technique. This approach may be translatable to human appendectomy procedures in the future.