Influence of 2 Veress needles and 4 insertion sites on Veress needle penetration depth: A comparative study in cadaveric dogs.

OBJECTIVE

To evaluate the penetration depth (VNPD) of 2 disposable Veress needles (VN) at 4 insertion sites in the abdomen.

STUDY

DESIGN

Descriptive study.

SAMPLE POPULATION: Canine cadavers (n = 22, 6 for confirmation of the test methods and 16 for the comparative study).

METHODS

Two disposable VN (VN A and VN B) were inserted at 4 sites (9th intercostal space [ICS] and preumbilical, paraumbilical, and subumbilical sites) in dorsally recumbent dogs by using a hand-cranked jig. The VNPD was measured as the distance traveled by the VN between the subcutaneous tissue and the perforation of the peritoneum on the basis of audible clicks and visible feedback from the VN. The effects of the VN type and insertion site on the VNPD were analyzed by using a linear mixed-effects model.

RESULTS

VNPD varied between insertion sites (P =  .01) and VN (P < .01). The VNPD was less at the 9th ICS than at the preumbilical, paraumbilical, and subumbilical sites. The maximal magnitude of change was 7.4 mm. Veress needle B (with a low spring rate, lower forces, and a back-cut bevel design) penetrated farther than VN A (with a high spring rate, high forces, and a lancet-type bevel) at 3 of 4 insertion sites. The maximal magnitude of change was 6.8 mm.

CONCLUSION

Veress needle penetration depth varied between VN designs but was the least at the 9th ICS in canine cadavers.

CLINICAL SIGNIFICANCE: Insertion of a VN at the 9th ICS is recommended to minimize its penetration into the abdomen. Associations between VNPD and mechanical factors, such as the sharpness and spring rate of VN, warrant additional research.