Suture or Hemostatic Agent During Laparoscopic Partial Nephrectomy? A Randomized Study Using a Hypertensive Porcine Model

Protective Topical Dual-Sided Nanofibrous Hemostatic Dressing Using Mussel and Silk Proteins with Multifunctionality of Hemostasis and Anti-Bacterial Infiltration

Topical hemostatic agents are preferred for application to sensitive bleeding sites because of their immediate locoregional effects with less tissue damage. However, the majority of commercial hemostatic agents fail to provide stable tissue adhesion to bleeding wounds or act as physical barriers against contaminants. Hence, it has become necessary to investigate biologically favorable materials that can be applied and left within the body post-surgery. In this study, a dual-sided nanofibrous dressing for topical hemostasis is electrospun using a combination of two protein materials: bioengineered mussel adhesive protein (MAP) and silk fibroin (SF). The wound-adhesive inner layer is fabricated using dihydroxyphenylalanine (DOPA)-containing MAP, which promotes blood clotting by aggregation of hemocytes and activation of platelets. The anti-adhesive outer layer is composed of alcohol-treated hydrophobic SF, which has excellent spinnability and mechanical strength for fabrication. Because both proteins are fully biodegradable in vivo and biocompatible, the dressing would be suitable to be left in the body. Through in vivo evaluation using a rat liver damage model, significantly reduced clotting time and blood loss are confirmed, successfully demonstrating that the proposed dual-sided nanofibrous dressing has the right properties and characteristics as a topical hemostatic agent having dual functionality of hemostasis and physical protection.

Comparison of off-clamp microwave scissors-based sutureless partial nephrectomy versus on-clamp conventional partial nephrectomy in a canine model

Objectives

To compare the usefulness and safety of off-clamp microwave scissors-based sutureless partial nephrectomy (MSPN) with on-clamp conventional partial nephrectomy (cPN) in dogs.

Methods

We performed off-clamp MSPN using microwave scissors (MWS) in six dogs, and on-clamp cPN in three dogs, in two-stage experiments. The bilateral kidney upper poles were resected via a midline incision under general anesthesia. After 14 days of follow-up, the lower pole resections were performed. The renal calyces exposed during renal resections were sealed and transected using MWS in off-clamp MSPN and were sutured in on-clamp cPN. In the off-clamp MSPN group, the generator's power output of MWS was set as either 50 W or 60 W for each kidney side. We compared the procedure time (PT), ischemic time (IT), blood loss (BL), and normal nephron loss (NNL) between the two techniques using the Mann-Whitney U-test.

Results

We successfully performed 24 off-clamp MSPNs and 12 on-clamp cPNs. The off-clamp MSPN was significantly superior to on-clamp cPN in avoiding renal ischemia (median IT, 0 min vs. 8.6 min, p < 0.001) and reducing PT (median PT, 5.8 min vs. 11.5 min, p < 0.001) and NNL (median NNL, 5.3 mm vs. 6.0 mm, p = 0.006) with comparable BL (median BL, 20.9 ml vs. 23.2 ml, p = 0.804). No bleeding and major urine leakage were noted during the reoperations.

Conclusions

Off-clamp MSPN outperforms on-clamp cPN in lowering the risks of postoperative renal function impairment in dogs.

Sutureless Purely Off-Clamp Robot-Assisted Partial Nephrectomy: Avoiding Renorrhaphy Does Not Jeopardize Surgical and Functional Outcomes

To compare outcomes of sutureless (SL) vs. renorrhaphy (RR) off-clamp robotic partial nephrectomy (ocRPN), we retrospectively analyzed procedures performed at our center, from January 2017 to April 2021, for cT1-2N0M0 renal masses. All the patients with a minimum follow-up < 1 month were excluded from the analysis. The trifecta rate defined surgical quality. Any worsening from chronic kidney disease (CKD) I-II to ≧ IIIa (from IIIa to ≧ IIIb, and from IIIb to ≧ IV) was considered as significant stage migration (sCKDsm). A 1:1 propensity score-matched (PSM) analysis minimized baseline imbalances between SL and RR cohorts in terms of age, gender, ASA score, baseline estimated glomerular filtration rate (eGFR), tumor size, and RENAL score. Logistic regression analyses identified predictors of trifecta achievement. Kaplan-Meier (KM) analysis assessed the impact of RR on significant chronic kidney disease sCKDsm-free survival (SMFS), while Cox regression analyses identified its predictors. Overall, 531 patients were included, with a median tumor size of 3.5 cm (IQR: 2.7-5); 70 (13%) presented with a cT2 mass. An SL approach was pursued in 180 cases, but 10 needed conversion to RR. After PSM analysis, patients receiving SL showed a higher trifecta rate (94% vs. 84%; p = 0.007). SMFS probabilities were comparable at KM analysis (log-rank = 0.69). Age (OR: 0.97; 95%CI: 0.95-0.99; p = 0.01), a RENAL score ≧ 10 (OR: 0.29; 95%CI: 0.15-0.57; p < 0.001), and RR (OR: 0.34; 95%CI: 0.17-0.67; p = 0.002) were independent predictors of trifecta achievement. Age (OR: 1.04; 95%CI: 1.003-1.07; p = 0.03) and baseline eGFR (OR: 0.99; 95%CI: 0.97-0.99; p = 0.05) independently predicted sCKDsm. Compared to RR, our experience seems to show that the SL approach significantly increased the probabilities of achieving the trifecta in the observed group of cases.

Clampless Laparoscopic Tumor Enucleation for Exophytic Masses Greater Than 4 cm: Is Renorrhaphy Necessary?

Objective: To demonstrate the safety of clampless 3D laparoscopic tumor enucleation (cLTE) for exophytic T1b kidney masses, avoiding suture to achieve hemostasis. Methods: Between January 2010 and January 2021, 241 consecutive patients with an exophytic renal tumor underwent sutureless cLTE. Patients with predominantly endophytic growth or tumors 4 mm closer to the collecting system less were excluded. In all cases, an attempt was made to accomplish surgery without suturing kidney parenchyma. Data were obtained from a retrospective review of history and physical examinations, operative and pathology reports, anesthesia records during the hospital stay, and follow-up visits. Results: Among 241 patients who underwent cLTE, 148 had cT1a and 93 had cT1b renal tumor. The median tumor size was 32 mm, and the median R.E.N.A.L. (radius exophytic/endophytic nearness anterior/posterior location) score was 6. Renorrhaphy was necessary in 5 cases. The median operative time (OT) was 100 minutes, and the estimated blood loss (EBL) was 150 mL. The median 24-hour decrease in hemoglobin was 1.8 g/dL. The median length of stay was 4 days. Nineteen patients had postoperative complications: 3 cases had Clavien-Dindo (CD) 3a or more, 6 had CD2, and 10 had CD1. Comparing the T1a and T1b groups, except for the median OT and the EBL, no significant differences were observed in all the other variables analyzed. In both groups, renal function was preserved after 1 year from surgery. Conclusion: Our experience showed that sutureless cLTE is safe and feasible for T1b tumors leading to radical oncological outcomes and preserving renal function.

Histological and radiological evaluation of thermal denaturation depth using soft coagulation during partial nephrectomy in living pigs

OBJECTIVES

To evaluate thermal denaturation depth using soft coagulation in kidneys in vivo.

METHODS

In experiment 1, nine kidneys from five pigs were cauterized using five soft-coagulation settings at 80 W with effect 7 by VIO300D and one monopolar-coagulation setting. The surface of the kidney was cauterized over a period of 2, 5 and 10 s. The temperature change was measured at depths of 5 and 10 mm. In experiment 2, three kidneys from two pigs were excised in a semicircular shape with a diameter of 5, 10 and 20 mm without clamping the renal artery. Cauterization was carried out until hemostasis was confirmed by soft coagulation at 80 W with effect 7. After completion of the experiments, pathology examinations of the kidneys were carried out.

RESULTS

Experiment 1 showed that with proper saline dripping, denaturation spread with increased cauterization time, reaching a depth of 4 mm at 10 s with or without clamps. The depth remained at 2-3 mm at 10 s in the absence or excess of saline. The temperature increased by 15.6°C at a depth of 5 mm and 8.8°C at 10 mm. In experiment 2, the depth was 4.6 mm from the incision surface regardless of the cauterization time or excision size.

CONCLUSIONS

These findings suggest that soft coagulation can be useful for preserving renal function and reducing complications in partial nephrectomy.

Nonischemic or Ischemic Laparoscopic Partial Nephrectomy Using a Newly Developed Hybrid Energy Device in a Porcine Model

Purpose: To compare the efficacy of a newly developed hybrid pencil-type energy device (HD) generating simultaneously monopolar high-frequency electric energy and ultrasonic energy with that of a conventional device (CD) during laparoscopic partial nephrectomy (LPN). Materials and Methods: A total of 16 female pigs (32 kidneys) were divided into 4 groups of 4 animals (8 kidneys) each: nonischemic and ischemic HD-LPN groups, and nonischemic and ischemic CD-LPN groups. We performed bilateral LPN for each pig. HD alone was used in the HD-LPN group, whereas commercially available monopolar scissors and a soft coagulation system were used in the CD-LPN group. After observing the postoperative course for 14 days, we euthanized the animals and harvested the kidneys for histopathological observations. Results: We completed an LPN on a total of 32 kidneys. There were no cases of conversion to open surgery, nor were there any deaths or complications requiring treatment. For nonischemic LPN, LPN time was significantly shorter in the HD-LPN group than in the CD-LPN group (11.4 ± 4.8 vs 17.7 ± 5.3 minutes, p = 0.027). The decrease in postoperative hemoglobin was equally low in both groups. However, the frequency of TachoSil^® use was significantly higher in the CD-LPN group than in the HD-LPN group (6/8 [75%] vs 0/8 [0%], p = 0.007). For ischemic LPN, we found no significant differences in parameters such as LPN time and using TachoSil between the two groups. The depth of thermal injury was the most superficial in the nonischemic HD-LPN group in comparison with the other three groups. Conclusions: The application of an HD allowed nonischemic LPN to be performed safely in a short time with less blood loss and less thermal injury to the kidney in the porcine model. Additional clinical investigations of human kidneys are required.

Robotic surgery and hemostatic agents in partial nephrectomy: a high rate of success without vascular clamping

Robot-assisted partial nephrectomy has been proposed as a technique to overcome technical challenges of laparoscopic partial nephrectomy. We prospectively collected and analyzed data from 31 patients who underwent robotic partial nephrectomy with systematic use of hemostatic agents, between February 2009 and October 2014. Thirty-three renal tumors were treated in 31 patients. There were no conversions to open surgery, intraoperative complications, or blood transfusions. The mean size of the resected tumors was 27 mm (median 20 mm, range 5-40 mm). Twenty-seven of 33 lesions (82%) did not require vascular clamping and therefore were treated in the absence of ischemia. All margins were negative. The high partial nephrectomy success rate without vascular clamping suggests that robotic nephron-sparing surgery with systematic use of hemostatic agents may be a safe, effective method to completely avoid ischemia in the treatment of selected renal masses.

Laparoscopic partial nephrectomy without intracorporeal suturing

BACKGROUND

Partial nephrectomy has gained wider acceptance as a surgical technique in treating small renal tumors. Laparoscopic partial nephrectomy (LPN) still remains a technically demanding surgery to this day. We present our technique of laparoscopic partial nephrectomy, one that is performed without intracorporeal suturing.

METHODS

We performed LPN on 31 patients with localized renal parenchymal tumor (stage T1). The procedures were done from September 2009 to March 2015 at the Kaohsiung Medical University Hospital and the Kaohsiung Municipal Ta-Tung Hospital. Our technique involves the covering of renal defect layer by layer with FloSeal, Tisseel and a fat pad after monopolar coagulation.

RESULTS

Thirty-one patients were included in this study. Mean patient age was 53 years old (range 39-70). Mean tumor size was 2.9 cm (range 1.8-6.3). Mean RENAL nephrometry score was 5.3 (range 4-7). The average operation time was 188 min (range 120-290), and the average warm ischemic time was 19.0 min (range 9-26). Mean estimated blood loss was 171 ml (range 10-650), with no postoperative bleeding among the total 31 patients. No recurrent tumors were identified at a mean follow-up of 29 months postoperatively. The mean change in eGFR was 6.5 (ml/min/m2).

CONCLUSION

Laparoscopic partial nephrectomy is a feasible surgical method for most patients with stage 1 tumor. Our technique has shown to reduce warm ischemic time significantly and provide patients with excellent functional outcomes without affecting oncological results. With this technique, surgeons can perform LPN with more efficiency and with fewer complications.

A combination of hemostatic agents may safely replace deep medullary suture during laparoscopic partial nephrectomy in a pig model

PURPOSE

We assessed whether a combination of the fibrin tissue adhesive Tisseel® (human fibrinogen and thrombin) plus the hemostatic matrix FloSeal® (bovine derived gelatin matrix/human thrombin) could safely replace the conventional deep medullary suture without compromising outcomes.

MATERIALS AND METHODS

Laparoscopic mid pole and one-third partial nephrectomy was performed on the right kidney of 12 female pigs. The only difference between the 2 groups of 6 pigs each was the use of a fibrin tissue adhesive plus hemostatic matrix combination in group 2 instead of the deep medullary running suture in control group 1. Renal scans and angiograms were performed at baseline and before sacrifice at 5-week followup. Retrograde in vivo pyelogram was also done.

RESULTS

No significant difference was seen in operative parameters or postoperative course between the groups. Renal scans revealed a statistically insignificant trend toward greater uptake loss in group 1 and angiograms showed 3 major vessel occlusions in that group. No active bleeding was detected. Those 3 kidneys had significantly poorer postoperative uptake on renal scan than that of other kidneys (18.6% vs 39.4%, p = 0.013). Only 1 small asymptomatic pseudoaneurysm was noted in group 1. No urine leakage was found in either group. No major vessel occlusion, pseudoaneurysm or urinary complications developed in group 2.

CONCLUSIONS

Even after deep one-third partial nephrectomy FloSeal with concurrent Tisseel appeared sufficient to control major medullary vascular injuries and replace the deep medullary conventional suture without compromising operative outcomes. The potential advantages seen during functional and vascular examinations by decreasing the risk of unnecessary segmental vessel occlusion need further clinical evaluation.

Postoperative adhesions after application of topical hemostatic agents: outcomes in a rat partial nephrectomy model

OBJECTIVE

To compare 3 kinds of topical hemostatic agents in terms of adhesive strength, control of hemorrhage, and postoperative intra-abdominal adhesions in an experimental partial nephrectomy (PN) model.

METHODS

A total of 27 Wistar rats were divided into 5 groups. PN was performed in 6 rats (control group) with the conventional technique, in which the lower pole of the kidney was excised and sutured after hilar control. In 5 rats, oxidized cellulose was placed over the excised part of the kidney following conventional technique. In 6 rats, the hemostatic plant extract was used without hilar control. In 5 rats, the hemostatic agent chitosan was used without hilar control. As a sham group, 5 rats underwent a laparotomy and handling of the renal pedicle without the removal of renal pole. On the tenth day after the operation, the degree of adhesions to the operated kidney were evaluated. Histopathological evaluation was also performed by a blinded pathologist.

RESULTS

Mean warm ischemia times for control and oxidized cellulose groups were 4.85 ± 0.75 and 4.28 ± 1.28 minutes, respectively (P = .662). Wound healing was excellent in all groups except in 1 rat in the chitosan group. Chitosan was associated with significantly higher intestinal and peritoneal adhesion scores, although histopathologically comparable scores were revealed.

CONCLUSION

In our rat model, chitosan and the hemostatic plant extract were as effective as conventional suturing in achieving hemostasis even without hilar control. Warm ischemia was eliminated and PN time was significantly decreased. The use of oxidized cellulose was not associated with higher scores of adhesion, suppuration, or hematoma.

Haemostatics in surgery and our experience in the enucleoresection of renal cell carcinoma

Background

30 patients, with T1 renal cell carcinomas (RCC) who underwent open enucleoresection of the tumour, were randomized to the use of a topical haemostatic agent (Floseal) or to an infrared-sapphire coagulator (ISC), to compare their efficacy in achieving haemostasis. Methods: Successful intra-operative haemostasis, intra- and post-operative bleeding, operative time, hospital discharge were evaluated.

Results

Statistically higher rates of successful haemostasis and shorter time-to-haemostasis (8,1 vs 12,9 min) were observed in the FloSeal group (p < 0.001 both). Patients operative time was not different between Group 1 vs 2 (58.7 ± 12 vs 62.4 ± 15; p > 0.05). The average blood loss during surgery was less (60 +/- 25.5 mL) for the FloSeal group than for the ISC group (85 +/- 40.5 mL) (p < 0.05). Postoperative blood loss was 25 +/- 5 mL and 40 +/- 45 mL for Floseal and ISC respectively, (p < 0.05). Length of the postoperative hospital discharge was 2.5 +/- 1.2 days for FloSeal group and 3.5 +/- 1.3 for the Group 2 (p < 0.05). No major immediate or delayed complications were observed in either Groups.

Conclusions

The use of Floseal and ISC offer a safe and efficacy haemostasis in the enucleoresection of RCC. Moreover, our results show a less intra-operative and post-operative blood loss as well as a shorter time to haemostasis of Floseal in respect to ISC.