Development and Validation of a Fully Automated, Experimental Set-Up for Ex-Vivo Burst Pressure Testing after Surgical Vessel Closure

Abstract

Background A growing number of operations are performed using minimally invasive techniques. Therefore, a lot of new requirements must be met by the staplers currently available. At the present time, the most widely used methods of minimally invasive vascular occlusion involve high-frequency energy, clips, and staplers. The most important quality parameter is burst pressure, which is measured with a variety of experimental set-ups, all of which are subject to criticism. With this study, we want to introduce a fully automated vascular burst pressure measuring system that largely mimics physiological conditions. An important feature of this set-up is the detection of very early leakage from the staple line (FAIR Leakage = First Appearance of Leakage requiring Intervention). Material and Methods Burst pressure was measured in vessel segments of porcine common carotid arteries. For vascular occlusion, we used the stapler device Micro Cutter XCHANGE® by DexteraSurgical. Prior to closure, the vessel was filled to a pressure of 80 mmHg. The pressure was increased at a defined flow rate. Burst pressure was defined as staple line leakage requiring intervention. Results and Validation 30 staple lines were examined. The average burst pressure visually determined by two independent investigators was 515.8 mmHg ± 236.3 mmHg. Maximal burst pressure was 911 mmHg, and minimal burst pressure 80 mmHg. The average burst pressure detected electronically was 511.8 mmHg ± 239.1 mmHg. Statistically, there was a highly significant correlation of visually and electronically detected burst pressures. Conclusion This is the first experimental set-up for a systematic burst pressure test that is fully automated and therefore eliminates any bias related to the investigator. The experimental set-up with a defined intravascular pressure prior to closure and the use of a liquid with blood-like viscosity enabled us to largely mimic intraoperative conditions. Since burst pressure is not defined as a complete rupture of the staple line, but as the moment of first occurrence of leakage requiring intervention, the results can be transferred into daily surgical practice.