Abstracts
1997 Digestive Disease Week

A randomized, prospective study of radially expanding trocars. Initial results of the Trocar Study Group.

S Bhoyrul, J Payne, B Steffes, L Swanstrom, W Gantert, LW Way. Stanford University Medical Center, Kaiser Hospital, Honolulu, North Carolina Laproscopy Center, Oregon Health Sciences University, and University of California, San Francisco.

This study consists of a multi-institutional trial of a new laparoscopic trocar with unique design features potentially of clinical value. The trocar enters the abdomen as a sheathed needle, and is deployed to its final operational diameter by radial dilatation. The trial tested the safety and efficacy of this device, the amount of postoperative pain from the trocar sites, the incidence of bleeding from the trocar sites, and whether the abdominal wall defects required closure.

All patients undergoing elective laparoscopic general surgical procedures at the participating institutions were invited to participate. After informed consent, they were randomized to the radially expanding trocars or conventional cutting trocars. Patient and procedure details, operative time, and intra-operative complications were recorded. The intention was not to close the fascial defects created by the radially expanding trocars unless they appeared to need closure for specific reasons. All fascial defects resulting from the conventional trocars were closed. The patients and independent observers were blinded as to the trocar type. Post-operative morbidity was recorded.

Sixteen surgeons performed 244 elective laparoscopic procedures. 119 were performed using radially expanding trocars (group R) and 125 were performed using cutting trocars (group C). The groups were similar in regard to age, sex, and procedure type, but group R contained more obese patients (body mass index of 140.0 vs. 129.4, p=0.02). Operative time was not different between the 2 groups. There were fewer episodes of intra-operative trocar site bleeding in group R (3 vs. 20, p<0.001). Other complications were similar in the two groups. Only 6 patients in group R had fascial defects of 10mm or greater that had to be closed (compared with routine closure in group C). With a follow up period of 6-12 months, there have been no incisional hernias in either group.

These results suggest that the radial expansion trocar is safe and effective and it is less likely than conventional cutting trocars to produce trocar site bleeding. Not having to close the fascial defects is another advantage.