Traditional electrosurgery and a low thermal injury dissection device yield different outcomes following bilateral skin-sparing mastectomy: a case report

Preclinical Comparison of Thermal Tissue Effects from Traditional Electrosurgery and a Low-Temperature Electrosurgical Device during Anterior Cervical Discectomy and Fusion

Background

Exposure of the anterior cervical spine requires dissection in proximity to critical neurovascular structures. Monopolar electrosurgical (ES) devices generate heat in contacted tissues, resulting in thermal damage and temperature change. This study examined depth of thermal injury and temperature change associated with use of a low-temperature electrosurgical device (LTD) compared to traditional electrosurgery during a cadaveric anterior cervical discectomy and fusion (ACDF) dissection.

Methods

ACDF was performed, using ES or LTD, on cervical spines (C3-4 and C4-5) from 2 fresh human cadavers with intact neck soft tissues and no history of surgery. Cadavers were maintained at 22-23°C, and fiber-optic temperature sensors (Neoptix, Québec City, Québec, Canada) were placed near relevant structures to measure changes during dissection. Depth of thermal injury was assessed by hematoxylin and eosin and Masson's trichrome histology of fixed tissue specimens.

Results

Use of the LTD resulted in a statistically significant reduction in temperature change at platysma (3.0 ± 1.04 vs. 11.41 ± 3.10°C, P = .003), carotid sheath (7.32 ± 1.13 vs. 15.57 ± 2.56°C, P = .007), and longus colli (6.11 ± 1.32 vs. 12.9 ± 3.62°C, P = .016) compared to ES. Temperature change at the trachea was similar between groups (6.06 ± 1.99 vs. 4.96 ± 1.89°C, P = .528). Histology showed that LTD produced less mean and maximal depth of thermal injury compared to ES (mean: 0.5 vs. 1.2 mm; max: 0.9 vs. 1.8 mm; P < .05).

Conclusions

The results of this pilot study demonstrate that anterior cervical spine exposure using an LTD reduces tissue temperature change and depth of thermal injury compared to ES.

Clinical Relevance

Although exploratory, these results suggest that use of an LTD during ACDF may reduce the extent of thermal tissue injury during dissection. Future studies in live animal models are warranted to determine if thermal injury is a potential cause of common exposure-related complications, such as dysphagia and dysphonia.

Effect of high-frequency electric field on the tissue sticking of minimally invasive electrosurgical devices

Generally minimally invasive surgery is performed using an endoscope and other instruments including electrosurgical units (ESUs), and the adhesion of tissue to electrodes is a major concern. The mechanism governing this tissue sticking, especially the influence of high-frequency electric field, is still unclear. In this study, the effect of high-frequency electric field on the tissue sticking upon electrodes was investigated. The electrosurgical cutting test was performed on ex vivo fresh porcine liver under blend mode using a monopolar ESU. A heat-adherence test without electric field was used as a control. For the control group, the electrode was heated and maintained at a certain temperature and directly in contact with porcine liver. Both sticking tissues obtained from these two tests are partially carbonized porcine liver tissue, but their microstructure and bonding with electrode are obviously different. The sticking tissue formed just under heat is composed of biggish nanoparticles of different sizes which are loosely aggregated and has a weak bonding with the electrode, while the sticking tissue from the electrosurgical cutting test consists of tightly packed fine nanoparticles of equable size as a result of thermo-electric coupling and has a strong bonding with the electrode. Obviously, high-frequency electric field plays an extremely important role in the formation of the sticking tissue. It is the thermo-electric coupling that underlies the function of minimally invasive electrosurgical devices, and the effect of high-frequency electric field cannot be ignored in the tissue sticking study and anti-sticking strategies.

An electrical plasma dissection tool for surgical treatment of chronic ulcers: Results of a prospective randomised trial

Cutaneous ulceration is a difficult medical problem and a major source of morbidity for patients. In the surgical treatment of ulcers, debridement is the first step, and it can be carried out using several surgical tools. Recently, new surgical devices have emerged using plasma-mediated electrical discharges with a lower peak temperature. A prospective single-blind trial was conducted on chronic ulcers not responsive to common non-surgical management. Patients were randomly separated into 2 groups: Group A received surgical debridement with conventional electrocautery, and Group B received surgical debridement using the plasma-mediated device. Histological samples were collected intraoperatively to evaluate the thermal damage during the surgical procedure and 2 weeks after surgery to evaluate the inflammatory response and collagen deposition. The width of coagulation necrosis at the incision margins in Group B was significantly shorter compared with Group A (P = .001). The inflammatory cell infiltration showed a cellular distribution percentage that was quite equal between the 2 groups. The granulation tissue showed an abundant deposition of dense and mature collagen in Group B, compared with Group A, where the mature collagen appeared in small quantities (P < .001). Microbial culture showed a lower incidence of postoperative infections in Group B compared with the control group (P < .05). The study demonstrated, based on the results, that the new technology with the use of a lower temperature electrosurgical device represents an effective therapeutic weapon for the surgical treatment of skin ulcers, both vascular and extravascular types.

Effect of Anti-Sticking Nanostructured Surface Coating on Minimally Invasive Electrosurgical Device in Brain

The purpose of the present study was to examine the extent of thermal injury in the brain after the use of a minimally invasive electrosurgical device with a nanostructured copper-doped diamond-like carbon (DLC-Cu) surface coating. To effectively utilize an electrosurgical device in clinical surgery, it is important to decrease the thermal injury to the adjacent tissues. The surface characteristics and morphology of DLC-Cu thin film was evaluated using a contact angle goniometer, scanning electron microscopy, and atomic force microscopy. Three-dimensional biomedical brain models were reconstructed using magnetic resonance images to simulate the electrosurgical procedure. Results indicated that the temperature was reduced significantly when a minimally invasive electrosurgical device with a DLC-Cu thin film coating (DLC-Cu-SS) was used. Temperatures decreased with the use of devices with increasing film thickness. Thermographic data revealed that surgical temperatures in an animal model were significantly lower with the DLC-Cu-SS electrosurgical device compared to an untreated device. Furthermore, the DLC-Cu-SS device created a relatively small region of injury and lateral thermal range. As described above, the biomedical nanostructured film reduced excessive thermal injury with the use of a minimally invasive electrosurgical device in the brain.

Biomedical electrosurgery devices containing nanostructure for minimally invasive surgery: reduction of thermal injury and acceleration of wound healing for liver cancer

The aim of the present study was to investigate the thermal injury in the liver after a minimally invasive electrosurgery technique with a copper-doped diamond-like carbon (DLC-Cu) surface coating. To effectively utilize electrosurgery in a clinical caner setting, it is necessary to suppress the thermal injury to adjacent tissues. The surface morphologies of DLC-Cu thin films were characterized using scanning electron microscopy and transmission electron microscopy. Three-dimensional liver models were reconstructed using magnetic resonance imaging to simulate the electrosurgical procedure. Our results indicated that the temperature decreased significantly when minimally electrosurgery with nanostructured DLC-Cu thin films was used, and that it continued to decrease with increasing film thickness. In an animal model, thermography revealed that the surgical temperature was significantly lower in the minimally invasive electrosurgery with DLC-Cu thin film (DLC-Cu-SS) compared to untreated electrosurgery. In addition, DLC-Cu-SS created a relatively small thermal injury area and lateral thermal effect. These results indicated that the biomedical nanostructure coating reduced excessive thermal injury, and uniformly distributed temperature in the liver.

Determinants of optimal mastectomy skin flap thickness

Background

There is a limited evidence base to guide surgeons on the ideal thickness of skin flaps during mastectomy. Here the literature relevant to optimizing mastectomy skin flap thickness is reviewed, including anatomical studies, oncological considerations, factors affecting viability, and the impact of surgical technique and adjuvant therapies.

Methods

A MEDLINE search was performed using the search terms ‘mastectomy’ and ‘skin flap’ or ‘flap thickness’. Titles and abstracts from peer-reviewed publications were screened for relevance.

Results

A subcutaneous layer of variable thickness that contains minimal breast epithelium lies between the dermis and breast tissue. The thickness of this layer may vary within and between breasts, and does not appear to be associated with obesity or age. The existence of a distinct layer of superficial fascia in the breast remains controversial and may be present in only up to 56 per cent of patients. When present, it may not be visible macroscopically, and can contain islands of breast tissue. As skin flap necrosis occurs in approximately 5 per cent of patients, a balance must be sought between removing all breast tissue at mastectomy and leaving reliably viable skin flaps.

Conclusion

The variable and unpredictable thickness of the breast subcutaneous layer means that a single specific universal thickness for mastectomy skin flaps cannot be recommended. It may be that the plane between the subdermal fat and breast parenchyma is a reasonable guide for mastectomy flap thickness, but this may not always correspond to a subcutaneous fascial layer.