Safe technique for laparoscopic entry into the abdominal cavity.

Study Objective: To evaluate and compare the safety and efficacy of a new method to enter the abdominal cavity at laparoscopy.

Design: (Canadian Task Force classification II-2).

Setting: Referral center for reproductive surgery in a teaching hospital affiliated with a university-based residency program.

Patients: Twenty representative women of variable body habitus (body mass index 16.5-39 kg/m2).

Intervention: Laparoscopy and laparotomy.

Measurements And Main Results: We measured the thickness of the abdominal wall at the base of the umbilicus and just below its inferior border. We also measured distances traversed by the Veress needle or cannula from skin to peritoneal cavity at both sites when the piercing instrument was directed at 45- or 90-degree angle from the horizontal plane of the abdominal wall. Finally, we measured distances created between parietal peritoneum and underlying viscera when the abdominal wall was lifted manually or with towel clips placed laterally, 2 cm from the umbilicus and at the edges of the intraumbilical incision. Distances created between parietal peritoneum and underlying viscera while lifting the abdominal wall by each of these three techniques were measured with a calibrated probe inserted through the intraumbilical port and observed with a 5-mm laparoscope from the suprapubic port. These distances were measured before and after carbon dioxide insufflation at 15 mm Hg, as well as before and while inserting the cannula through the abdominal wall. Mean +/- SD thickness of the abdominal wall at the base of the umbilicus and lower border of the umbilicus were 1.4 +/- 0.5 and 3.0 +/- 1.1 cm, respectively (p <0.01). Distances traversed by piercing instruments through the abdominal wall at the umbilicus and lower border of the umbilicus when the angle of insertion was 45 degrees were 1.98 +/- 0.76 and 4.24 +/- 1.53 cm, respectively (p <0.01). Distances were significantly greater when the angle of insertion was 45 degrees rather than 90 degrees. Distances between parietal peritoneum and underlying viscera when the abdominal wall was lifted manually with towel clips 2 cm from the umbilicus, or at the edges of the intraumbilical incision were 3.5 +/-1.14, 5.14 +/- 1.04, and 6.8 +/- 0.94 cm, respectively (p <0.01). When force was applied on the abdomen at cannula insertion, these distances were reduced by 2.1 +/- 0.91, 1.03 +/- 0.32, and zero centimeters, respectively (p <0.01).

Conclusion: Our technique of inserting the cannula perpendicularly through the base of the umbilicus traverses the shortest distance to the abdominal cavity through the least vascular area of the abdominal wall. Lifting the abdominal wall with towel clips placed at the edges of the intraumbilical incision achieves the greatest distance between parietal peritoneum of the abdominal wall and underlying viscera, thus maximizing the margin of safety in protecting peritoneal organs and retroperitoneal vessels from injury.