Systems and instruments for laparoscopic surgery without pneumoperitoneum

The insufflation of carbon dioxide into the peritoneal cavity is a routine technique of abdominal exposure in laparoscopic surgery. Because of adverse physiological effects and technical disadvantages of the pneumoperitoneum, alternative methods of abdominal wall lifting have been explored recently. Two groups of retraction systems exist: intraabdominal lifting and subcutaneous lifting of the abdominal wall. Some systems require additional pneumoperitoneum, because the extent of intraabdominal exposure is not sufficient. Other systems are working completely without gas insufflation. Two systems combine abdominal wall lifting with pressure on the internal organs. Every method allows the use of standard laparoscopic instruments, which originally were designed for a regular pneumoperitoneum. The use of a low-pressure pneumoperitoneum in combination with mechanical augmentation of the peritoneal cavity reduces physiological disadvantages of laparoscopy. But technical advantages, such as combination of laparoscopic and open techniques, can be realized only without gas insufflation. Conventional instruments have been designed to fit the ergonomical needs of isopneumic laparoscopy and to be employed with simple valveless cannulae. Received: 19 November 1996/Accepted: 30 December 1997