Evaluation of a chest wall lift technique in feline cadaveric specimens

Abstract

Objective: To evaluate the effect of a simple chest wall-lifting technique on thoracic volumes in cats. Study design: Cadaveric study. Animals: Feline cadavers (n = 8). Methods: Animals underwent thoracic computed tomography (CT) scans after each treatment: in lateral recumbency, (1) no lift and (2) intercostal space lift, and in dorsal recumbency, (1) no lift and (2) sternal lift. Lifting was performed in lateral recumbency at the eighth intercostal space using a bent 2 mm Steinmann pin and in dorsal recumbency at mid-sternum using a Backhaus towel clamp, placed under thoracoscopic guidance until maximal effect was subjectively noted while recording the tension achieved on the device. Thoracic cavity volume (TCV), working space volume (WSV), and ventilation space volume (VSV) were determined on CT images and compared across treatments. Results: The TCV increased by a median of 27% (range: 7%–72%), 54% (28%–64%), and 51% (37%–106%) in the dorsal, left lateral, and right lateral recumbencies, respectively. The WSV showed a median increase of 92% (−21%–1026%), 187% (113%–355%), and 271% (119%–422%) for the same positions. In contrast, the VSV decreased, and although statistically significant, the change was relatively minor, with a median decrease of 3% (range: −5%–19%), 7% (−1%–18%), and 7% (3%–11%) in the dorsal, left lateral, and right lateral recumbencies, respectively. Conclusion: Chest wall lifting increased the WSV in feline cadavers with minimal impact on the VSV. Clinical significance: This novel and simple technique could help in performing thoracoscopic procedures in cats.