Division of the small bowel with the LigaSure Atlas device during the right laparoscopic colectomy

Ex-Vivo Evaluation of "First Tip Closing" Radiofrequency Vessel Sealing Devices for Swine Small Intestinal Transection

This study compared burst pressure (BP), number of activations, and histological assessment of ex vivo swine small intestine loops transected by stapler, a single fulcrum radiofrequency vessel sealing (RFVS) device, and the newly-developed jaws RFVS. Fifty (n = 50) 20 cm long jejunal loops were randomly assigned to be transected with RFVS devices and linear stapler (Caiman5, Caiman Maryland, Caiman12, Ligasure Atlas, and Stapler group as control respectively). Caiman5, Caiman12 and stapler required only one activation to complete the sealing. The mean BP in Caiman5 and Caiman Maryland groups were significantly lower (p < 0.05) than the S group as control and the other RFVS devices studied. RFVS Caiman12 and Ligasure Atlas produced mean BP values that were close to the Control and did not differ between them. The lumen was totally closed in the Caiman12 and Ligasure Atlas groups. The findings of this investigation were promising; we discovered that Caiman12 and Ligasure Atlas produce comparable mechanical capabilities as well as stapled intestinal closure, however Caiman12 need a single activation to complete the transection.

Swine Small Intestine Sealing Performed by Different Vessel Sealing Devices: Ex-Vivo Test

This study aimed to evaluate the sealing quality of swine small intestine using different laparoscopic radiofrequency vessel sealing devices (two 5 mm: RFVS-1 and -2; one 10 mm: RFVS-3) and a harmonic scalpel (HS) compared to golden standard closure technique. The study was divided into two arms. In study arm 1: n = 50 swine intestinal loops (10 per group) were transected with each instrument and the loops in which the devices provided complete sealing, at the gross inspection, were tested for maximum burst pressure (BP) and histological evaluation and compared to an automatic linear stapler. After the BP tests, the devices that achieved significantly lower BP values were excluded from the second arm. The RFVS-1 and -3 provided statistically significant results and were used in study arm 2, to obtain full-thickness biopsies along the antimesenteric border of the loop and were compared with hand-sewn intestinal closure (n = 30; 10 per group). The biopsies were histologically evaluated for thermal injury and diagnostic features, and intestinal loops tested for BP. RFVS-3 achieved comparable results (69.78 ± 4.23 mmHg, interquartile range (IQR) 5.8) to stapler closing technique (71.09 ± 4.22 mmHg, IQR 4.38; p > 0.05), while the RFVS-1 resulted in significantly (p < 0.05) lower BP (45.28 ± 15.23 mmHg, IQR 24.95) but over the physiological range, conversely to RFVS-2 (20.16 ± 7.19 mmHg, IQR 12.02) and HS (not measurable). RFVS-3 resulted not significantly different (p > 0.05) (45.09 ± 8.75 mmHg, IQR 10.48) than Suture (35.71 ± 17.51 mmHg, IQR 23.77); RFVS-1 resulted significantly lower values (23.96 ± 10.63 mmHg, IQR 9.62; p < 0.05). All biopsies were judged diagnostic. Data confirmed that RFVS-1 and -3 devices provided suitable intestinal sealing, with BP pressures over the physiological range. Conversely, the HS and RFVS-2 should not be considered for intestinal sealing. RFVS devices could be employed to obtain small intestine stump closure or full-thickness biopsies. However, further studies should be performed in live animals to assess the role of the healing process.

Comparison of the use of a vessel-sealing device versus ligatures for occlusion of uterine tissues during ovariohysterectomy or ovariectomy in rabbits (Oryctolagus cuniculus)

OBJECTIVE

To compare the bursting strength of the uterine horns (UHs) and cervical-vestibule junction (CVJs) of rabbits following sealing with a vessel-sealing device (VSD) or encircling ligatures.

SAMPLE

UHs and CVJs collected from 30 rabbit (Oryctolagus cuniculus) cadavers.

PROCEDURES

UHs and CVJs were randomly assigned to sealing with encircling Miller knot ligatures (LIG; n = 10 CVJs and 20 UHs) or a VSD (12 CVJs and 24 UHs). Lumens were infused with saline (0.9% NaCl) solution under pressure until seals burst or to a maximum pressure of 300 mm Hg.

RESULTS

For CVJs, median (range) bursting pressure of the LIG and VSD groups was > 300 mm Hg (224 to > 300 mm Hg) and 35 mm Hg (0 to 60 mm Hg), respectively. Five of 12 CVJs in the VSD group failed at pressures < 33 mm Hg. For UHs, median (range) bursting pressure of the LIG and VSD groups was 255 mm Hg (120 to > 300 mm Hg) and 154 mm Hg (range, 44 to 202 mm Hg), respectively.

CONCLUSIONS AND CLINICAL RELEVANCE

The evaluated VSD was effective in sealing UHs at bursting pressures well in excess of expected physiologic pressures, indicating that the VSD may be useful for ovariectomy procedures in rabbits. However, CVJ seals created with the VSD were ineffective and could potentially burst at low pressures, which could predispose to urine entering the abdomen. Given these results, we do not recommend sealing of the CVJ with a VSD for ovariohysterectomy in rabbits.

Evaluation of the LigaSure(™) Vessel Sealing System for bowel transection and intestinal anastomosis-an experimental study in a porcine model

BACKGROUND

The purpose of the present study is to assess the value of the LigaSure™ Vessel Sealing System (LVSS) as a means for bowel transection and intestinal anastomosis.

METHODS

We compared the LVSS for (1) transecting bowel and (2) creation of an intestinal anastomosis with standard methods such as stapler (S) and hand-sewn (HS) in a porcine model. For each study arm, i.e., bowel transection and anastomosis creation, both the small bowel and colon were examined. In total, ten transections and ten anastomoses were performed for each. Burst and anastomotic leak pressures were compared.

RESULTS

In the study arm 1, LVSS achieved lowest burst pressures in both small bowel (LVSS 39.8 ± 3.6 mmHg, S 81.9 ± 3.9, HS 111.9 ± 14.7 mmHg, p < 0.0001) and colon transections (LVSS 21.5 ± 2.6 mmHg, S 79.5 ± 4.9, HS 91.0 ± 5.2 mmHg, p < 0.0001). There was no difference in burst pressures between S and HS in both small bowel and colon transections. In the study arm 2, LVSS showed the lowest anastomotic leak pressures for small bowel (LVSS 26.4 ± 2.6 mmHg, S 52.1 ± 6.2, HS 87.4 ± 7.0 mmHg, p < 0.0001) and colonic anastomoses (LVSS 16.9 ± 1.3 mmHg, S 55.9 ± 4.3, HS 74.4 ± 4.4 mmHg, p < 0.0001). Furthermore, small bowel and colonic anastomoses using S demonstrated significantly lower leak pressures than HS anastomosis p < 0.001 and p = 0.004, respectively.

CONCLUSIONS

The LVSS achieves significantly lower burst pressures and anastomotic leak pressures for bowel transection and intestinal anastomosis than S and HS techniques. However, due to the achieved pressure levels of 39.8 ± 3.6 mmHg, LVSS appears to be a sufficient stand-alone method for bowel transection. Whether it can be used to perform intestinal anastomosis warrants further research in a survival model.

Colorectal anastomosis facilitated by the use of the LigaSure(®) sealing device: comparative study in an animal model

BACKGROUND

Recently, there has been speculation about the possibility of fusing intestinal tissue using bipolar sealing devices. In this study we compare in a porcine model the anastomoses created using the LigaSure(®) device with those created with a stapler after section and closure of a rectal stump.

METHODS

Thirty pigs underwent laparoscopic colorectal anastomosis. In group A (n = 15), the division of the intestine and distal stump closure were done with a 10-mm LigaSure Atlas(®) device. In group B, these steps were carried out using an endoscopic stapler. Subsequently, the colorectal anastomosis was performed using circular stapling in both groups. The 4-week follow-up included health status, weight gain, blood tests, X-rays, and colonoscopy. Anastomotic tissue was processed to study the mechanical tensile strength and histopathology.

RESULTS

There was no difference in the rate of conversion to open surgery or in average operating time between the groups. In the sealing device group, there was a significantly higher rate of failure in rectal stump closure (p = 0.042). There was one death in group B due to anastomotic leak. There was no difference in adhesion formation or stenosis. Mid-section anastomosis area was 89.7 mm(2) in group A compared with 100 mm(2) in group B (p = 0.52). In tensile strength studies, the maximum load resisted by the sample was 13.8 ± 4.9 N (group A) versus 15.7 ± 4.4 N (group B) (p = 0.17). There was no difference between the groups in degree of reepithelialization, number of inflammatory cells, or the presence of microabscesses.

CONCLUSIONS

Division and sealing of the rectal stump with the LigaSure(®) device is feasible in the proposed experimental model, but it is less reliable than conventional closure with a stapler, since it has a significantly greater failure rate. Therefore, The LigaSure(®) device should not be used for this purpose in the clinical setting as this could lead to serious and dramatic complications.

The nightknife©: evaluation of efficiency and quality of bipolar vessel sealing

BACKGROUND

Nightknife(©) is a novel reusable bipolar vessel sealing device. In the present study we analyzed its efficiency and quality of vessel sealing in comparison to a standard instrument (LigaSure™).

MATERIALS AND METHODS

Mesenteric veins and arteries of 5 Swabian-Hall pigs were sealed by means of Nightknife and LigaSure. Thermal performance of both devices was assessed by dynamic thermography. Analysis of the sealed vessels included the determination of seal failure rates and heat-associated macroscopic tissue appearance.

RESULTS

The overall sealing rate of Nightknife was significantly higher than that of LigaSure (95.8% versus 87.0%; P=.012). This was associated with a more pronounced thermal spread (8.22±0.13 versus 7.12±0.10 mm; P=.012) and tissue desiccation (2.15±0.06 versus 1.86±0.07; P=.003). Moreover, sealing time (12.30±0.17 versus 7.72±0.17 seconds; P=.038) and tissue temperature (93.73°C±0.69°C versus 66.71°C±2.18°C; P=.001) were significantly higher with the use of Nightknife. Logistic regression analysis revealed that the degree of tissue desiccation correlated with the overall sealing success.

CONCLUSION

Nightknife is as appropriate as LigaSure for the successful sealing of mesenteric vessels despite significant differences in tissue alterations and sealing time between the two devices.