| ObjectiveSurgical system which applies low temperature plasma is a disruptive technique in the history of electrosurgery, which core technique is that using pulsed radio frequency technique, high electric field creates plasma in front of the end of knife and overheating of water by a plasma-mediated discharge causes explosive vaporization and rapid expansion of a vapor bubble that fragments or ablates tissue. This effect is limited into the surface layer of tissue in the condition of relatively low temperature, which leads to less thermal injury to the adjacent tissue. However, this technique is monopolized by the western countries. Domestic experimental prototype of new surgical system which applies low temperature plasma (NTS-100) is manufactured by the PLA General Hospital and Beijing Notus Technology Co. Ltd. The result of initial animal skin experiment demonstrates that local working temperature is lower than the most advanced electrosurgical devices [eg. the pulsed-electron avalanche knife (PEAK)PlasmaBlade device (Medtronic Inc., USA)] and produces less thermal injury; that the function of incision and coagulation is better; that the scar of the end of knife is less;that wound healing is also improved. After 1-yeared improvement and optimization, the engineering prototype is also manufactured finally. The object of this experiment is to evaluate the effectiveness and safety of the new surgical system which applies low temperature plasma (NTS-100) and provide experimental evidences for the register of this device.MethodsThe advantages and disadvantages of NTS-100 are evaluated in the porcine abdominal operation, including cutting, hemostasis, thermal damage and the others, by comparing with high frequency electrotome (Valley) and the PlasmaBlade (PEAK). The indexes are including local working temperature, the amount of bleeding, the region of coagulation necrosis, operative fluency, etc.Twelve piglets were randomly divided into three groups, each group underwent the operation using NTS-100, Valley or the PEAK, respectively. The experimental data were analyzed statistically by SPSS 22 software.1. Cutting and coagulation experiment in liver and spleen(1) Calculate the amount of bleeding in the operation using the method of filter paper absorption.(2) Record the tip temperature of each instrument in the operation using infrared camera.(3) Measure the width of acute thermal injury zone using specimens stained with hematoxylin and eosin (HE) and image processing software.2. Coagulation experiment in blood vesselsObserve active bleeding and delayed bleeding after 1 hour in the closed end of the mesenteric vascular, the retinal vein, the splenic vein and the abdominal wall vein,which were cutted in the coagulation model by the three surgical scalpels, following measuring the diameter of the blood vessels.3. Partial resection of liver lobe experimentRecord the total bleeding volume, the operation time, the cutting area, the number of ligation and calculate the cutting speed, the amount of bleeding per unit area, the number of ligation per unit area by performing partial resection on the porcine left external hepatic lobe, left internal hepatic lobe and the right external hepatic lobe,simulating the real partial resection of liver in clinical surgery.4. Surgical fluency evaluationEvaluate the cutting sharpness, the tissue adhesion after coagulation and surgical smoke as using the three surgical scalpels.Results1. Cutting and coagulation experiment in liver and spleen(1) The amount of bleedingIn the liver experiment, the amount of bleeding using Valley, PEAK, or NTS-100 in the incision model was 1.377±0.358g、1.597±0.382g、1.383±0.429g, respectively.There was no significant difference in the amount of bleeding among the three surgical scalpels in the same model (P>0.05).In the spleen experiment, the amount of bleeding using Valley, PEAK, or NTS-100 in the incision model was 1.388±0.506g、1.672±0.283g、1.542±0.433g, respectively.There was no statistically significant difference (P>0.05). In the coagulation model,the amount of bleeding in the NTS-100 was 0.762±0.290g, significantly less than that of the Valley (1.170±0.364g) and PEAK (1.233±0.454g) (P<0.05).(2) Local working temperatureIn the liver experiment, local working temperature using NTS-100 in the incision model was 75.3±6.1 ℃,significantly lower than Valley ( 204.6±20.5℃) ( P <0.01) ,and comparable to PEAK (77.4±6.1±)(P>0.05) .In the coagulation model,local working temperature using NTS-100 was 195.8±15.4℃, significantly lower than Valley (272.3±26.6℃)(P<0.01),and comparable to PEAK (198.2℃±14.3℃)(P>0.05).In the spleen experiment, local working temperature using NTS-100 in the incision model was 69.4±11.1℃, significantly lower than Valley (226.8±30.0℃ ) (P<0.01 ),and comparable to PEAK (78.0±7.9℃ )(P>0.05 ) .In the coagulation model, local working temperature using NTS-100 was 199.8±16.9℃,significantly lower than Valley ( 267.8±42.5℃ ) ( P < 0.01 ) , and comparable to PEAK(213.8±18.8℃) (P>0.05).(3) HistologyIn the HE stained specimens of liver surgical margin, the width of acute heat injury of NTS-100 in the incision model was 399.35±125.37μm,significantly less than that of Valley ( 718.27±169.91μm) (P< 0.05), comparable to PEAK ( 312.00±70.53μm )(P>0.05) . In the coagulation model, the width of acute heat injury of Valley, PEAK,and NTS-100 wasl670.91±341.36μm、1378.50±216.22μm 、1462.60±201.54μm,respectively, there was no statistically significant difference among these three electrosurgical devices (P> 0.05).In the HE stained specimens of spleen surgical margin, the width of acute heat injury of NTS-100 in the incision model was 391.80±60.02μm,significantly less than that of Valley (808.75±81.35)(P<0.05),comparable to PEAK (371.75±97.06μm)(P>0.05) . In the coagulation model, the width of acute heat injury of NTS-100 was 893.43±176.23μm,significantly less than that of Valley (1221.13±269.11 ) (P<0.05),comparable to PEAK (891.88±164.23μm)(P>0.05).2. Coagulation experiment in blood vessels(1)Coagulating success rate of NTS-100 on the mesenteric vascular with average diameter of 1.5mm was 100%, and delayed bleeding rate was 0%. There was no statistically significant difference, comparing with Valley and PEAK (P>0.05);(2) Coagulating success rate of NTS-100 on the retinal vein, splenic vein and abdominal wall vein with average diameter of 3.56mm was 100%, delayed bleeding rate was 0%. The longest diameter of 4.53mm could be coagulated successfully. There was no statistically significant difference, comparing with Valley and PEAK (P>0.05).3. Partial resection of hepatic lobe experimentNTS-100 could be used to complete the lobectomy. There was no statistically significant difference in the ability of cutting, coagulation, comparing with Valley and PEAK (P> 0.05).4. Surgical fluency evaluation(1)The cutting experiment to skin, muscle, fat and other soft tissues showed that the sharpness of NTS-100 was better than that of Valley and PEAK, and the operation smoke was less;(2)The cutting experiment to omentum, fascia and other smaller impedance of the membrane tissue showed that the sharpness of NTS-100 was comparable to Valley, both of them was better than that of PEAK;(3)The cutting experiment to liver, spleen and other tissues with rich blood supply showed that the sharpness of NTS-100 was comparable to PEAK, both of them was better than that of Valley. The scab adhered to NTS-100 was less and easier to fall off than Valley.Conclusion1. Local working temperature of new surgical system which applies low temperature plasm (NTS-100) is significantly lower than Valley which is commonly clinically used, and lower than PEAK which is the most advanced electrosurgical device.There is less region of acute heat injury and less operation smoke produced as used NTS-100 than the others.2. Coagulation effect of NTS-100 to soft tissues and tissues with rich blood supply,including liver and spleen, is comparable to high frequency electrotome.3. Vessels with diameter less than 3.5mm could be coagulated reliably by NTS-100,comparable to high frequency electrotome.4. The sharpness of NTS-100 to soft tissues is better than the Valley and PEAK,The scar adhered to the tip of NTS-100 is less and easier to fall than the Valley. The operation fluency using NTS-100 is excellent. |
PDF Full Text Request