[Natural orifice transluminal endoscopic surgery (NOTES): initial experimental results]

The advent of natural orifice endoscopic surgery (NOTES) and new prototypes for performing this surgical procedure led us to design an experimental animal surgical programme.

NOTES was performed over a period of one year, in sows, following the European guidelines on the use of experimental animals. Ninety operations were performed with no animals surviving. The following aspects were assessed: 1. Access route complexity (transgastric, transvaginal, transesophageal and transumbilical). 2. Support measures for temporal/spatial orientation. 3. Technical possibilities for visceral orifice closure (clips, T-bars, Obesco clips and endoscopic suture). Resections of fallopian tubes, ovaries, gallbladder, mediastinal lymph nodes, tail of the pancreas and gastrojejunal derivations were performed with one or two endoscopes.

This experience enabled us to highlight a series of technical aspects essential for these techniques: 1. Pneumoperitoneum with CO(2) is safer for entry. 2. Orifice size is important to limit contamination. 3. Puncture entry and guided dilation is safer. 4. Good gastric exit location makes it easier to approach viscera to be resected. 5. Intra-abdominal haemorrhage is difficult to control. 6. Leak-free closure cannot be guaranteed with clips, but t-bars and Obesco clips may be effective. 7. Endoscopes that permit triangulation may facilitate the dissection and endoscopic suture.

NOTES requires a multidisciplinary team comprising laparoscopic and endoscopic surgeons. Pure NOTES is complex and hybrid forms or transumbilical route could be intermediate steps.