Assessment of laparoscopic injuries by three methods

Lethal haemorrhage due to erosion of external iliac artery in a patient with ureterovaginal fistula following endometriosis surgery

We present a case report of a patient with laparoscopic surgery of a deep infiltrating endometriosis with a complicative course. In addition to a postoperatively diagnosed ureteral fistula with local inflammation, acute perforation and ultimately lethal bleeding from the adjacent external iliac artery occurred more than 3 weeks after surgery. To the best of our knowledge, a case with the same constellation has not yet been published. A literature review on the rare and comparable complication of a ureteroarterial fistula is discussed in connection with the case.

Thermal spread of vessel-sealing devices evaluated in a clinically relevant in vitro model

INTRODUCTION

Bipolar vessel-sealing devices (VSDs) have advantages in urological surgeries (less hemorrhage, shorter operating time). However, these instruments can cause thermal injuries, which can result in neural damage and necrosis. The objectives of this study were to establish a reproducible in vitro model for standardized assessment of electrosurgical devices and to evaluate whether optimized placement of surgical instruments can reduce the thermal spread.

METHODS

We evaluated thermal spread of two VSDs in vitro using thin bovine muscle strips. Thermal injury was measured using an infrared camera, temperature probes and histology. The recordings were made with the VSD alone and with a rectangular clamp next to the VSD.

RESULTS

Both instruments showed a significant temperature spread of 2.5 mm lateral to the VSD. The placement of a metal clamp next to the VSD significantly reduced the temperature spread. Histological examinations were able to underline these findings.

CONCLUSIONS

In this study we describe a straightforward clinically relevant in vitro model for the evaluation of future electrosurgical instruments. We demonstrated that the thermal spread of VSD could be further reduced by optimized placement of an additional surgical instrument. Our results could help surgeons protect sensitive structures like nerves in the vicinity of the VSD.

Intelligent, impedance-regulated, pulsed coagulation in a porcine renal artery model

OBJECTIVE

To compare the efficacy of conventional pulsed coagulation (CPC) and newly developed intelligent, impedance-regulated, pulsed coagulation (IPC) in the sealing of porcine renal arteries.

DESIGN

Prospective, randomized experimental study.

SETTING

Isolated porcine artery model in an academic research environment.

ANIMAL(S)

Female Swabian Hall pigs.

INTERVENTION(S)

Renal arteries were harvested from Swabian pigs, flushed with saline, and sealed with bipolar open forceps by using high-frequency modulations of CPC (CPC-I: 800-ms pulse, 30-ms pause; CPC-II: 800-ms pulse, 300-ms pause) or IPC (self-regulation of the current flow to tissue impedance during thermal alteration). Additional vessels underwent multiple CPC. Burst pressure and seal failure were measured by increasing the pressure in the sealed arteries with saline infusion until rupture of the seal or the vessel wall.

MAIN OUTCOME MEASURE(S)

Mean burst pressure, number of instant and secondary seal failures, and relation of burst pressure to vessel diameter.

RESULT(S)

Mean burst pressure after IPC (585.5 +/- 56.8 mm Hg) was statistically significantly higher than that after CPC (CPC-I: 372.6 +/- 40.0 mm Hg; CPC-II: 334.2 +/- 44.2 mm Hg). Only 5.0% of the vessel seals after IPC, but 34.0% and 39.5% after CPC-I and CPC-II, showed instant or secondary seal failures, which also was a statistically significant difference. Seal quality after multiple CPC was comparable to that observed after the single IPC application (burst pressure, 597.3 +/- 60.1 [MCPC-I] mm Hg and 656.2 +/- 56.5 mm Hg [MCPC-II]; seal failure rate, 0).

CONCLUSION(S)

In an isolated porcine renal artery model, self-regulating modulation of energy-based vessel coagulation achieved superior thermal fusion of vascular tissue than did CPC. This promising novel technique should be analyzed further to determine its in vivo efficacy in long-term studies.