Predicting burst pressure of radiofrequency-induced colorectal anastomosis by bio-impedance measurement

Abstract

The present study investigates the relationship between bio-impedance and burst pressure of colorectal anastomosis created by radiofrequency (RF)-induced tissue fusion. Colorectal anastomosis were created with ex vivo porcine colorectal segments, during which 5 levels of compression pressure were applied by a custom-made bipolar prototype, with 5 replicate experiments at each compression pressure. Instant anastomotic tensile strength was assessed by burst pressure. Bio-impedance of fused tissue was measured by Impedance Analyzer across frequency that 100 Hz to 3 MHz. Statistical analysis shows only a weak correlation between bio-impedance modulus and burst pressures at frequency of 445 kHz ( ρ s = −0.426, P = 0.099 > 0.05). In contrast, results demonstrated a highly significant negative correlation between reactance modulus and burst pressures ( ρ s = −0.812, P = 0.000 < 0.05). The decrease in mean reactance modulus with increasing burst pressures was highly significant (P = 0.019 < 0.05). The observed strong negative correlation between reactance modulus and burst pressures at frequency of 445 kHz indicates that reactance is likely to be a good index for tensile strength of RF-induced colorectal anastomosis, and should be considered for inclusion in a feedback loops in devices design. Institute of Physics and Engineering in Medicine3 Contribute equally.

An ex vivo preliminary investigation into the impact of parameters on tissue welding strength in small intestine mucosa-mucosa end-to-end anastomosis

“…The mechanical mechanism of thermo-fusion involves protein denaturation, cross-linking, and reannealing, which can be influenced by several parameters including ICP, pressure, and temperature ( Zhao et al, 2015a ). Previous studies have demonstrated that the average BP increases with an increase in ICP before reaching the optimal range ( Arya et al, 2013 ; Zhao et al, 2015b ; Zhao et al, 2017 ). However, beyond this range, an increase in ICP does not result in increased BP ( Arya et al, 2013 ).…”

“…In 2013, an anastomotic de-vice based on existing LigaSureTM technology was used to conduct mucosa-mucosa side-to-side anastomoses on porcine bowel ex vivo ( Arya et al, 2013 ). In 2015–2017, Zhao et al ( Zhao et al, 2015a ; Zhao et al, 2015b ; Zhao et al, 2017 ) has done extensive work on serosal-serosal end-to-end anastomosis of porcine intestines. While there is extensive research on serosa-serosal end-to-end anastomosis, there is limited published data on mucosa-mucosa end-to-end anastomosis, which is essential to avoid secondary injury to the body ( Smulders et al, 2007 ; Winter et al, 2010 ; Arya et al, 2013 ; Zhao et al, 2015a ; Zhao et al, 2015b ; Zhao et al, 2017 ).…”

“…In 2015–2017, Zhao et al ( Zhao et al, 2015a ; Zhao et al, 2015b ; Zhao et al, 2017 ) has done extensive work on serosal-serosal end-to-end anastomosis of porcine intestines. While there is extensive research on serosa-serosal end-to-end anastomosis, there is limited published data on mucosa-mucosa end-to-end anastomosis, which is essential to avoid secondary injury to the body ( Smulders et al, 2007 ; Winter et al, 2010 ; Arya et al, 2013 ; Zhao et al, 2015a ; Zhao et al, 2015b ; Zhao et al, 2017 ). Therefore, it is crucial to study the parameters affecting the strength of small intestinal mucosa-mucosa end-to-end fusion, providing experimental support for clinical research of intestinal anastomosis without foreign body residue and subsequent tissue regeneration.…”

Preliminary study of a control algorithm for radio-frequency-induced intestinal tissue fusion

“…The injection needle was inserted into the un-fusion port of the tissue and clamped using hemostatic forceps to ensure that burst occurred at the fusion area of the tissue. The constant-flow pump injected 0.9% saline into the tissue at a constant rate of 2 ml/min [14]. The output voltage signal of the pressure transducer was transmitted to the PC through the DAQ card.…”

“…Under the vessel sealing mechanism based on the RF energy, the collagen in the vessel forms a new hinge to achieve the effect of vessel sealing [7][8][9][10][11][12]. Because the small intestine tissue contains a certain amount of collagen [13], some scholars suspect that the tissue can be fused by RF energy [6,[14][15][16][17][18]. If this method is successful, it would have significant advantages over the traditional manual suture and stapler anastomosis methods.…”