Ultrasonically activated device for parenchymal division during open hepatectomy

Oncological safety of use of ultrasonic activated shears in gastric cancer surgery: Long-term results of randomized controlled trial

Objective

Ultrasonically activated shears (UAS) have been applied in open gastric surgeries with no or little evidence. It was previously reported about the surgical outcome and effectiveness of UAS based on a randomized controlled trial of 256 patients with gastric cancer. We aimed to clarify the long-term oncological safety of the use of UAS in the aspect of overall survival and recurrence.

Methods

Gastric cancer patients who underwent gastrectomy with D2 lymph node dissection were enrolled and randomly assigned to either the conventional surgery group (n=125) or the UAS group (n=128). Survival, recurrence and long-term postoperative complications were compared between the two groups. The median follow-up period was 56 months.

Results

Gastric cancer-related death was higher in patients of the UAS group compared with the conventional group (P=0.019). Overall survival rates stratified by stage were not significantly different between the two groups (P=0.170). Disease-free survival rates stratified by stage and recurrence-free survival rates of gastric cancer were similar between the conventional group and the UAS group (P=0.313 and 0.199, respectively). The postoperative complication rate was not significantly different between the groups (P=1.000).

Conclusions

It is suggested that the use of UAS in gastrectomy for gastric cancer showed oncologically acceptable safety compared with conventional electric instruments even in long-term period.

Viability of Airborne Tumor Cells during Excision by Ultrasonic Device

Background. Laparoscopic surgery has become more widely used, but peritoneal dissemination and port-site metastasis have been reported to occur in these surgeries. One reason for these problems is the ultrasonically activated scalpel (UAS) used for laparoscopic surgery. This study aimed to investigate the viability of airborne cells released during cancer dissection using a UAS. Methods. Flank tumors measuring about 2 cm were induced in male NOD-Cg-Rag1^tm1MomIL2rg^tm1wjl/SzJ mice by subcutaneous injection of 1 × 10⁶ HepG2 cells. Dissection was performed with UAS (in high or low power modes) and PowerStar bipolar scissors. The mist of released tissue was collected in cell culture medium. The viability of the cellular material was assessed with trypan blue exclusion cell counting, counting after immunofluorescence staining, and flow cytometric analysis. Results. Large quantities of cellular debris were trapped in the tissue dispersed by both devices. In all experiments, there were significantly more viable cells produced by the UAS in high power mode. By using suction at the excision site, the number of viable cancer cells was reduced. Conclusions. This study demonstrates that viable cancer cells can be released into the nearby environment during tumor ablation with a UAS.

Efficacy of a half-grip technique using a fine tip LigaSure™, Dolphin Tip Sealer/Divider, on liver dissection in swine model

BACKGROUND

Recently, a lot of energy devices in the surgical field, especially in the liver surgery, have been developed, and a fine tip LigaSure™, Dolphin Tip Sealer/Divider (DT-SD) also has been used frequently to dissect liver parenchyma as well as ultrasonically activated device (USAD). However, the utility of this instrument for liver dissection (LD) is still unknown. Moreover, to reduce bleeding during LD, a half-grip technique (HGT) was contrived. We herein report an experimental study in swine model to evaluate the feasibility and effectiveness of HGT using DT-SD for LD.

METHODS

The swine model experiment was carried out under general anesthesia by veterinarians. LD was performed repeatedly by DT-SD with the HGT (Group A, n = 6), or the conventional clamp-crush technique (CCT) (Group B, n = 6), and by variable mode USAD (Group C, n = 6). The dissection length and depth (cm) as well as bleeding volume (g) were measured carefully, and the dissection area (cm(2)) and speed (cm(2)/min) were calculated precisely. Histological examinations of the dissection surfaces were also executed. Mann-Whitney's U test was used for Statistical analyses with variance at a significance level of 0.05.

RESULTS

Among the three groups, the three averages of dissection lengths were unexpectedly equalized to 8.3 cm. The dissection area (cm(2)) was 9.9 ± 5.1 in Group A, 9.8 ± 4.7 in Group B, and 9.9 ± 4.5 in Group C. The mean blood loss during LD was 10.6 ± 14.8 g in Group A, 41.4 ± 39.2 g in Group B, and 34.3 ± 39.2 g in Group C. For Group A, the bleeding rate was the least, 0.9 ± 1.0 g/cm(2), and the average depth of coagulation was the thickest, 1.47 ± 0.29 mm, among the three groups (p < 0.05). The dissection speed in Group A (1.3 ± 0.3 cm(2)/min) was slower, than that in Group C (p < 0.05).

CONCLUSIONS

This report indicates firstly that the HGT using DT-SD bring the least blood loss when compared with CCT or USAD. Although the HGT is feasible and useful for LD, to popularize the HGT, further clinical studies will be needed.

Ultrasonically activated shears versus electrocautery in open gastrectomy for gastric cancer: a randomized controlled trial

BACKGROUND

Use of ultrasonically activated shears (UAS) is gaining popularity in open surgery but without concrete evidence. We conducted a prospectively randomized study to assess the efficacy of ultrasonic dissection in open gastrectomy for gastric cancer.

METHODS

Patients with gastric cancer who were to undergo gastrectomy with D2 lymph node dissection were enrolled and assigned to either the conventional surgery group (n = 125) or the UAS group (n = 128).

RESULTS

The mean operating time was significantly reduced in the UAS group (89.3 ± 15.6 min) when compared to the conventional group (97.8 ± 17.2 min; p < 0.001). However, we did not find any significant difference in operative blood loss, the amount of postoperative abdominal drainage, or the rate of postoperative complications between the groups. A multivariate analysis for operating time revealed that the use of UAS, female gender and BMI less than 25 were significantly associated with reduced operating time. The operating time was significantly longer in the conventional group than in the UAS group (B 7.786; 95 % CI 4.103-11.468; p < 0.001). In the subgroup analysis, the use of UAS significantly reduced the operating time, especially in male patients, regardless of the BMI status.

CONCLUSIONS

The use of UAS in gastrectomy for gastric cancer was a safe and efficient method, especially in terms of reducing operating time for male patients.

A new method for hepatic resection and hemostasis: absorbable plaque and suture

OBJECTIVE

Blunt and penetrating hepatic injuries are conditions that are frequently encountered in emergency surgeries, and they involve high mortality morbidity. In the handling of such injuries, methods ranging from the application of simple cauterization and suturing for hemostasis to hepatic lobectomies, which might involve the removal of the greater part of the organ, have been defined. Due to the organ's fragility and susceptibility to bleeding, elective hepatic resections necessitate both surgical experience and technological equipment. Therefore, the demand still exists for an affordable and easy-to-use-method that could be applied by all centers.

MATERIALS AND METHODS

To meet this demand, we have developed a method of hemorrhage control via sutures supported by absorbable plaques that provide effective compression and prevent the suture from cutting the tissue during the application of the sutures in the treatment of such fragile organs as the liver. In our method, we have achieved hemostasis by bilaterally compressing the tissue through strong ties after placing, on the part of the tissue on which the sutures are applied, absorbable and flexible plaques that prevent the suture from cutting the tissue during the application of a polyglactin suture to the solid organ. To prevent dislocation of the plaques, we have fastened the sutures by reeving them through the holes made in the plaques.

RESULTS

We have demonstrated the success and the practicality of our method by applying it on four pigs; we experimentally inflicted hepatic injuries on two pigs, and we performed resection on the other two pigs. The hepatic hemorrhages we developed in both of the animals were successfully restrained by the use of our method. On the other hand, two resections were performed on the right and left lobes of the other two animals. There were no hemorrhages during the surgery, and the procedure took 45 minutes in total. No postoperative complications occurred. While the liver function test values were high on the seventh day, due to the operation, they were observed to be normal on the thirtieth day. After the laparotomies, performed six months later, we observed that the plaques as well as the sutures were absorbed and that the injured tissues were completely healed. Additionally, it was observed during the pathological examination that the tissues beneath the area of application were healed through fibrosis and that the liver had no other pathologies.

CONCLUSIONS

In conclusion, we believe that the method can be safely used in hepatic resections or traumatic hemorrhages in the proper locations.