INTRODUCTION: There is currently interest in further expanding the capabilities of flexible endoscopic surgery to accomplish procedures that presently require laparoscopic access. Natural orifice transluminal endoscopic surgery (NOTES) is a new and rapidly evolving hybrid procedure in which flexible endoscopic technology is used to perform intra-abdominal laparoscopic surgical procedures. Flexible endoscope based endoluminal surgical procedures show promise as a less invasive form of surgery. Potential patient advantages include no pain, no skin incisions, avoidance of general anaesthesia, transfer of many procedures to the outpatient area and possibly reduced procedure cost. Elevated intraabdominal pressure due to gas insufflation for transgastric intraabdominal surgery may result in hemodynamic, gasometric and regional blood flow changes. Carbon Dioxide (CO2) is traditionally used for intraperitoneal insuflation during laparoscopic surgery and absorption of CO2 via the peritoneal surfaces lead to hypercapnia and respiratory acidosis. As we know, the majority of endoscopic insufflators run with air and only few of them with CO2. Therefore the objective of the present study was to compare two groups of animals in which we performed a NOTES procedure with CO2 and with air in different pressures, recording hemodynamic and gasometrical changes in both groups and also with a conventional CO2 laparoscopic group in order to establish which one is better.
METHODS: We included 32 animals; in 11 of them we used CO2 and air in the other 11 and we performed a NOTES procedure. 5 animals were used to establish the procedure and 5 to the control laparoscopic group. We performed a NOTES assisted transgastric cholecystectomy and recorded hemodynamic, pulmonary and hormonal parameters.
RESULTS: Hemodynamic parameters: We observed significant differences between the group of animals of NOTES-air and the group of laparoscopy, related with the heart frecuence, but not between the group of NOTES-CO2 and the group of NOTES-air. We did not observe any other significant difference related with cardiac index or mean arterial pressure between the groups. Pulmonary parameters: We did not observe significant differences between groups, but the group of laparoscopy with CO2 presented a higher tendency to hypercapnia and acidosis. Regarding hormonal response, we observed a worse clearance of Lidocaine in the group of laparoscopy and higher levels of Renine and Aldosterone in the group of NOTES.
CONCLUSIONS: We did not observe significant differences in hemodynamic parameters between the groups of NOTES-air and NOTES-CO2 in our group of animals. We appreciated minor hypercapnia and acidosis in NOTES group compared with laparoscopic group. The group of NOTES presented better metabolic hepatic function and a higher stress response compared with the laparoscopic group.
Program Number: P261