Comparison of a reusable with a disposable vessel-sealing device in a sheep model: efficacy and costs

Safety and effectiveness of a novel generator algorithm for bipolar vessel sealing: a randomised controlled chronic animal study

BACKGROUND

Electrosurgical vessel sealers are gradually replacing conventional techniques such as ligation and clipping. Algorithms that control electrosurgical units (ESU), known as modes, are important for applications in different surgical disciplines. This chronic porcine animal study aimed to evaluate the safety and effectiveness of the novel thermoSEAL electrosurgical vessel sealing mode (TSM). The BiClamp® mode (BCM) of the renowned VIO® 300 D ESU served as control. BCM has been widely available since 2002 and has since been successfully used in many surgical disciplines. The TSM, for the novel VIO® 3 ESU, was developed to reduce sealing time and/or thermal lateral spread adjacent to the seal while maintaining clinical success rates. The primary aim of this study was to investigate the long-term and intraoperative seal quality of TSM.

METHODS

The BiCision® device was used for vessel sealing with TSM and BCM in ten German Landrace pigs which underwent splenectomy and unilateral nephrectomy during the first intervention of the study. The seals were cut with the BiCision® knife. Ninety-nine arteries, veins and vascular bundles were chronically sealed for 5 or 21 days. Thereafter, during the second and terminal intervention of the study, 97 additional arteries and veins were sealed. The carotid arteries were used for histological evaluation of thermal spread.

RESULTS

After each survival period, no long-term complications occurred with either mode. The intraoperative seal failure rates, i.e. vessel leaking or residual blood flow after the first sealing activation, were 2% with TSM versus 6% with BCM (p = 0.28). The sealing time was significantly shorter with TSM (3.5 ± 0.69 s vs. 7.3 ± 1.3 s, p < 0.0001). The thermal spread and burst pressure of arteries sealed with both modes were similar (p = 0.18 and p = 0.61) and corresponded to the histological evaluation. The measured tissue sticking parameter was rare with both modes (p = 0.33). Tissue charring did not occur. Regarding the cut quality, 97% of the seals were severed in the first and 3% in the second attempt (both with TSM and BCM).

CONCLUSIONS

The novel TSM seals blood vessels twice as fast as the BCM while maintaining excellent tissue effect and clinical success rates.

TRIAL REGISTRATION

Not applicable.

Performance and microbiological safety testing after multiple use cycles and hydrogen peroxide sterilization of a 5-mm vessel-sealing device

OBJECTIVE

To evaluate the functional and microbiological safety of a single-use laparoscopic vessel-sealing device in a multiuse setting.

STUDY DESIGN

Ex vivo study.

SAMPLE POPULATION

Twelve 5-mm LigaSure Maryland jaw devices.

METHODS

Handsets underwent repeated test cycles until failure. The handset packaging was opened, and handsets were agitated in phosphate-buffered saline (PBS). The PBS was removed, centrifuged, and submitted for culture. Canine ovariectomy was simulated on cadaveric tissue, after which vascular seal quality was evaluated by pressure testing of sealed porcine carotid arteries. The handsets were cleaned and sterilized with hydrogen peroxide gas and repackaged.

RESULTS

Mean ± SD cycles to failure was 7.7 ± 2.8, with a minimum of 4 and a maximum of 12 use cycles achieved. Eleven of the 12 handsets failed by failure of handset activation after depression of the activation trigger. Only 1 handset failed to hold an adequate vascular seal under 300 mm Hg of pressure. No handset exhibited positive bacterial culture at any cycle.

CONCLUSION

The sterilization method used in this study resulted in an excellent microbiological safety profile. Most of the handsets failed by activation button failure.

CLINICAL SIGNIFICANCE

Under the conditions of this study, hydrogen peroxide sterilization achieved microbiological safety. Handsets can successfully be reused until activation button failure without negative effects on the vascular seal or increased risk of infection to the patient.

Bipolar vessel-sealing devices in laparoscopic hysterectomies: a multicenter randomized controlled clinical trial

OBJECTIVE

To compare operating time and blood loss in patients undergoing total laparoscopic hysterectomies (TLH) for benign conditions with either the Marseal™ IQ 5 mm (MS) or the Ligasure™ 5 mm (LS) vessel-sealing device.

DESIGN AND SETTING

A randomized controlled clinical trial (RCT) in two German gynecology departments.

PATIENTS

74 patients scheduled to undergo TLH for a symptomatic fibroid uterus, adenomyosis or severe meno-metrorrhagia.

INTERVENTIONS

Patients were randomized to receive a TLH with either the MS or the LS device. 27 variables were prospectively collected to address potential confounding issues.

MEASUREMENT AND MAIN RESULTS

Operating time, defined as the time period between the first (round ligament dissection) and the last (uterine vessels sealing) use of the device, estimated and calculated intraoperative blood loss. The mean operating time (95% confidence interval, CI) was 22.7 min (95% CI 17.6-27.7) for LS and 26.4 min (95% CI 20-32.8) for the MS device (p = .89). The estimated intraoperative blood loss was 164 ml (95% CI 110-217) for LS and 160 ml (95% CI 116-203) for the MS device (p = .36). The multivariate analyses accounting for BMI, endometriosis, uterine weight and appearance of fibroids did not reveal any significant effect of the type of device used on operating time and estimated blood loss.

CONCLUSION

In this RCT, both devices provided reliable and effective sealing and dissection. The reusable MS showed non-inferiority against the disposable LS device with regard to operating time and estimated intraoperative blood loss.

Bond Strength of Thermally Fused Vascular Tissue Varies With Apposition Force

Surgical tissue fusion devices ligate blood vessels using thermal energy and coaptation pressure, while the molecular mechanisms underlying tissue fusion remain unclear. This study characterizes the influence of apposition force during fusion on bond strength, tissue temperature, and seal morphology. Porcine splenic arteries were thermally fused at varying apposition forces (10-500 N). Maximum bond strengths were attained at 40 N of apposition force. Bonds formed between 10 and 50 N contained laminated medial layers; those formed above 50 N contained only adventitia. These findings suggest that commercial fusion devices operate at greater than optimal apposition forces, and that constituents of the tunica media may alter the adhesive mechanics of the fusion mechanism.

Economics and energy sources

Energy-based instrumentation has not only facilitated the rapid adoption of laparoscopic surgery, but could be considered essential for the completion of abdominal and pelvic procedures under endoscopic guidance. For decades, relatively simple and generic reusable monopolar and bipolar systems were the only options available. More recently, the available options for energy-based surgical instrumentation have become more crowded with the introduction of ultrasound-based cutting and sealing instruments and proprietary, impedance monitoring radiofrequency coagulation devices. Such instrumentation is presented as being easier to use as well as providing greater safety and efficacy. However, these new instruments typically require the expenditure of capital for proprietary energy generators and are usually designed to be for single use, a circumstance that increases per case costs, a circumstance that begs the question of value. Do the additional costs expended for the more expensive devices translate into reduced complications, faster operating time, or even wider access to minimally invasive procedures because they enable more surgeons to offer the service? Herein is explored the complex economic issues associated with the use of energy-based surgical devices as they apply to minimal access surgery in general and to laparoscopic procedures specifically.

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.