Physics for Surgeons - Part 4: Energy Devices in Surgery

Modern surgery has advanced astoundingly in the last century owing to the advent of number of energy devices in the operation room. Surgeon in the past were only using electric current –monopolar diathermy to burn and couterize the tissue, the present day surgeons are equiped with a number of more advanced energy devices e.g. LASER, ultrasonic vibrating shears, radiofrequency, shockwaves, argon beam coagulator and advanced bipolar electric energy with hybrid systems and light energy of different wavelengths. In the present paper, we have explained the physical principles involved in the commonly used energy devices in the operation theatre.

Skin ligation and argon beam coagulation for giant pachydermatocele resection

Resection of giant neurofibroma in neurofibromatosis type 1 has a high risk of perioperative bleeding because the tumors are enriched in blood vessels, which are weakened due to the loss and thinning of vascular smooth muscle. Therefore, we combined skin ligation around the tumor and use of an argon beam coagulator (ABC) for hemostasis during resecting the giant neurofibroma. The ABC is a non-contact-type hemostasis device employing argon gas as a medium. We examined the usefulness of our method by retrospectively comparing the outcomes of the ABC-use group with those of the non-use group (7 patients, 9 tumors). Although there was no difference in resected tumor weight between the two groups, the operation time was slightly shorter and the volume of blood loss was smaller in ABC-use group than in the non-use group. Our method for hemostasis is easy and safe and is considered to be a useful method.

A Comparison of Thermal Plasma Energy Versus Argon Beam Coagulator-Induced Intestinal Injury After Vaporization in a Porcine Model

ObjectivesComplete cytoreduction of ovarian cancer often requires excision or ablation of bowel serosa implants. Both argon beam coagulator (ABC) and thermal plasma energy (TPE) (PlasmaJet; PlasmaSurgical, Roswell, Ga) have been used to ablate bowel serosa implants. Our objective was to identify comparable power settings as well as determine the rate of bowel perforation, depth of thermal injury, and extent of inflammatory response with ABC versus TPE in a porcine model.Materials and MethodsNine pigs underwent vaporization of small bowel and colon serosa according to assigned treatment group (TPE vs ABC) and settings (ABC: 30, 50, and 70 W; TPE: Cut 10U, 20U, and 30U and Coagulation 10U, 20U, and 30U). Animals underwent necropsy with blinded histomorphologic evaluation on days 0, 3, and 10 postprocedure to assess for presence of bowel perforation, depth of thermal injury, and extent of inflammatory response.ResultsAt necropsy, bowel perforation was not identified in any animals. Depth of treatment with ABC in the porcine colon was variable and unrelated to power settings whereas TPE was associated with a consistent treatment depth of 1.0 mm regardless of location or power. Treatment with ABC resulted in greater tissue coagulation and desiccation as well as increased rates of mucosal necrosis, especially at higher settings (>50 W). Treatment with TPE primarily resulted in tissue ablation and minimal mucosal necrosis at low settings (Coag 10U–20U). The inflammatory response associated with TPE treatments was interpreted as biologically benign, and less than that observed with the ABC regardless of treatment settings.ConclusionsBoth ABC and TPE effectively ablate bowel serosa in a porcine model. The TPE seems to result in a more predictable tissue effect with less inflammatory response, especially when used at low power settings such as Coag 10U or 20U. These characteristics are appealing for ablation of bowel serosa implants during ovarian cancer surgery and warrant further investigation.