Examination of resistance of various methods of pulmonary vessel occlusion to hydrostatic pressure

The aim of this study was to compare pressure resistance of the most common methods of vessel occlusion during thoracic surgical procedures: ligations, clips, and vascular endostaplers.

Pulmonary vessels were obtained during routine thoracic surgeries. A ball-tipped cannula was inserted through an opening in the side wall and secured with a linen ligature from slipping out. Subsequently, saline was infused into the vessel. We recorded the pressure on which a leakage occurred.

A total of 65 vessels, divided between 3 groups, were enrolled in the study. In the endostaplers group, median bursting pressures were 262.5 mmHg and 300 mmHg for arteries and veins, respectively. In the case of clips, it was over 750 mmHg in both types of the vessels. The same results were observed in the ligation group. Minimal bursting pressures in endostapler occlusion were 187.5 mmHg and 225 mmHg in arteries and veins, respectively. In the case of clips, it was 600 mmHg for arteries and 675 mmHg for veins. A total of 525 mmHg (arteries) and 750 mmHg (veins) were the minimal leaking values observed in vessels occluded with ligations. Comparative analysis showed statistically significant differences in endostapler-clips and endostapler-ligations pairs (p < 0.001). There were no differences between clips and ligations.

The examined methods are capable of occluding pulmonary vessels under physiological conditions. Furthermore, ligations and clips are resistant to pressures highly exceeding physiological values.