Influence of Veress Needle Types and Implantation Sites on Peritoneal Tenting: A Comparative Study in Cadaveric Dogs

Objective:
To evaluate the influence of mechanical properties and sites of insertion of Veress needles (VN) on peritoneal tenting.
Study Design: Descriptive study.

Animals:
Canine cadavers (n = 16).

Materials and Methods:
In 16 cadaveric dogs, two different disposable VN (VN A and VN B) selected from a previous study because of their differences in their spring rate, were inserted on eight different sites into the abdomen in order to achieve a capnoperitoneum. The distance the VN had to overcome between the insertion in the subcutaneous tissue and perforating the peritoneum, defined as the peritoneal tenting in this study, was measured and compared. VN A was the one with a high spring rate, whereas VN B demonstrated the lowest spring rate.

Results:
For both needles, a significant smaller peritoneal tenting was observed when inserted in the 9th ICS compared to pre- umbilical (p= 0.002) and sub-umbilical (p= 0.001) regions. Comparing the insertion sites for each VN separately, VN A also showed significant differences for pre-umbilical (p= 0.020) and sub-umbilical (p= 0.026) compared to the 9th ICS. Furthermore, significant differences were seen when comparing the needles on each insertion site: VN B showed significant smaller peritoneal tenting on the pre-umbilical (p= 0.023), para-umbilical (p= 0.016) and sub-umbilical (p= 0.038) insertion site compared to VN A.

Conclusion:
The type of needle as well as the insertion site has a significant influence on the peritoneal tenting.