Polymer clips (Hem-o-lok®

Objective: To describe our experience using polymer clips (Hem-o-lok®) for renal vessel control in laparoscopic living donor nephrectomy (LLDN). Materials and methods: We conducted a retrospective and descriptive analysis from our database of all minimally invasive living donor nephrectomies (hand-assisted and pure laparoscopic) performed from 2008 to 2020 in our institution. We included patients who underwent LLDN using polymer clips (Hem-o-lok®) for vascular control of renal arteries and veins, and whose clinical records were complete. Results: 330 LLDN were performed, 183 (55.5%) were hand-assisted nephrec-tomies and 147 (44.5%) were pure laparoscopic nephrectomies. Mean warm ischemia time (WIT) was 3.98 minutes and median of estimated blood loss (EBL) was 100±140 ml. Four patients (1.2%) required conversion to an open procedure due to vascular injury. 31 complications (9.3%) were registered, of which 23 (6.9%) were non-life-threatening complications. No deaths nor loss of renal grafts were reported. Limitations:

staples to control renal vessels. (8) Nevertheless, stapler misfire present in up to 1.7% of LLDN. (9) Furthermore, the use of stapling devices represents higher costs for patients and healthcare systems in comparison polymer clips. For that reason, proving that the use of polymer clips is a safe and effective method for vascular control in LLDN could be a valid contribution for low-and mid-income healthcare systems or to reduce out-of-pocket expenses to patients.
The aim of our study was to describe the experience in our Tertiary-care center using polymer clips (Hem-o-lok ® ) for vascular control during LLDN. (8)

Materials and methods
We

Results
A total of 380 LLDN were performed between 2008 and 2020 at our center. We excluded 50 patients due to incomplete information regarding vascular control device used or perioperative variables, leaving 330 LLDN suitable for analysis.

Postoperative outcomes
Thirty one complications (9.3%) were registered during the 30-day postoperative period, of which 23 (6.9%) were modified Clavien-Dindo grade 1 (Non-life-threatening complications); five (1.5%) were grade 2a complications (one pulmonary embolism, three pneumonias, and one intraabdominal abscess managed conservatively); there were only three (0.9%) grade 2b complications in two patients (one patient with a pancreatic fistula and an intraabdominal fluid collection requiring percutaneous drainage; and one patient with a pleural effusion and an intraabdominal abscess requiring thoracentesis and percutaneous drainage). Description is summarized in Table 2. No deaths nor loss of renal grafts were reported.

Intraoperative Complications
Conversion to open surgery 4 2c

Discussion
In However, the use of staplers is not free from complications, which have been reported to happen in 1-2% of the cases. (11,12) In this study, we  (14,15) Regarding other intraoperative characteristics in our series, mean WIT, EBL and operative time are comparable to those reported by other groups using staplers, without clinical difference. (16)(17)(18) Recently, a meta-analysis comparing the use of polymer clips and vascular staplers for donor nephrectomies found no differences in terms of mechanical failure rate, intraoperative bleeding or death confirming that the correct use of both devices is safe. ( Figure 2 shows the cost differences between using stapling devices compared to polymer clips after 20 procedures. Estimating a cost of $521 USD per patient in the stapler group results in a total expense of $10,000 USD after 20 procedures. Conversely, the estimated cost of the clip applicator is $2,000 USD, while the cost of 10mm (purple) and 15mm (gold) Hem-o-lok® cartridges is $21 and $40 USD, respectively, resulting in an approximate expense of $3,300 USD after 20 procedures. Therefore, when using polymer clips, we reach a cost-benefit advantage after 5-6 procedures.

Conclusions
According to our results, the use of self-locking polymer clips is a safe method for vascular control of the renal hilum vessels in LLDN. A careful dissection and refined surgical technique are essential to avoid perioperative complications. Additionally, this method appears to be the most cost-effective option, with similar outcomes when compared to stapling devices.

Financing
No sponsorship was received to write this article.