Objective: To create a novel construct for lift laparoscopy in dogs and to determine the maximum lift capacity of the construct and lift force required for maximal cranial abdominal visualization.
Methods: A 3-D-printed ring (3DPR) was designed for a study conducted from December 1, 2023, to January 20, 2024, to articulate with 2 sizes of a commercially available polyurethane wound retractor (PWR). The PWR and 3DPR were attached to a hanging trapeze following insertion into miniature laparotomies on the ventral abdomen. In 8 cadavers, load was applied to the construct to determine its maximum tensile capabilities. In 6 cadavers, laparoscopic images of the diaphragm were attained at different abdominal wall lift forces based on the percentage of body weight. Diaphragmatic visibility was scored, and diaphragmatic surface area was calculated to determine lift force for maximal cranial abdominal visualization.
Results: Visible diaphragmatic surface area was greatest during body wall lifting at 15% body weight (median, 162.56 cm2; IQR, 132.88 to 212.38 cm2) compared to 20% body weight (median, 139.26 cm2; IQR, 105.23 to 155.10 cm2). Median failure force was greater for small (18.01; IQR, 15.51 to 23.00 kilogram-force) versus extra-small (11.65; IQR, 9.63 to 13.00 kilogram-force) 3DPR/PWR constructs. Median failure force for both 3DPR/PWR construct sizes occurred at > 43% of the body weight.
Conclusions: The findings of this study demonstrate the preclinical feasibility of a novel construct for cranial abdominal lift at low tensile loads in canine cadavers.
Clinical relevance: The construct reported here may represent an effective lift laparoscopy alternative to capnoperitoneum for cranial abdominal procedures in dogs at risk of complications during abdominal insufflation.
Keywords: 3-D printing; abdominal wall lifting; lift laparoscopy; minimally invasive surgery; polyurethane wound retractors.