The Effects of Natural Orifice Translumenal Endoscopic Surgery (NOTES) on Cardiorespiratory Physiology

Introduction. Despite the increasing awareness of natural orifice translumenal endoscopic surgery (NOTES), there remain obstacles to its wider implementation. We aim to examine the current evidence for the effects of variable uncontrolled insufflation pressures using either air or carbon dioxide in NOTES, as well the effects of NOTES procedures themselves, on physiological parameters. Method. We undertook a systematic review of all publications relating to the effects of NOTES on physiology, in particular compared with laparoscopy. Results. Eleven reports were identified comprising comparative trials involving a total of 237 pigs. With one exception, no difference was found between the effect of NOTES and laparoscopic surgery on cardiopulmonary parameters. No difference was found also for the effect on inflammatory mediators such as interleukin-6. Two studies also assessed the effects choice of insufflation gas, with no change in inflammatory markers. Two further studies assessing the effects of variable pneumoperitoneal pressures found negative cardiorespiratory effects with higher pressures. Discussion. Existing evidence is limited to small-sample animal trials but appears to show noninferiority for NOTES compared with laparoscopy. The development of a pressure regulation device for NOTES must be considered.