Tissue sealant aids in collecting system repair

Charleston, SC- A two-component synthetic tissue sealant may serve as a viable alternative to current standard suturing techniques used in collecting system repair, according to researchers from Duke University, Durham, NC. Their research used a swine model to compare two FDA-approved sealants and traditional suturing.

Tissue sealants are most often used to assist in hemostasis, but their role has been broadened to include assistance in closure of fistulous tracts and applications outside of the genitourinary system, Dr. Springhart said during a presentation at the AUA Southeastern Section annual meeting.

"Other sealants are available that mimic differing aspects of the clotting cascade, but recent concerns over the potential side effects of a xenograft, such as bovine collagen, in the human body are being evaluated," Dr. Springhart said.

Comparing sealants To compare the sealants with standard suturing, Dr. Springhart and colleagues conducted a survival study of 15 swine. The animals were divided into three groups: BioGlue, Crosseal, and control. Open partial nephrectomy was performed on the lower pole of the right kidney via a retroperitoneal approach in all animals; a large collecting system injury was created during the procedure.

Hemostasis was obtained via electrocautery and 4.0 chromic suture in all three groups.

In the control group, collecting system repair was achieved by closing the defect with a running 3.0 vicryl suture. Surgical bolsters were placed to ensure hemostasis.

In the experimental groups, either BioGlue or Crosseal was applied to the dry surface of the kidney for closure of the collecting system and adjuvant hemostasis. A Jackson-Pratt drain was placed adjacent to the repair in all animals, and output was monitored daily. The animals were sacrificed 1 week after the procedure.

Right nephroureterectomy was performed, with intraoperative assessment for urinoma and hematoma, and collecting system leakage was evaluated during ex vivo retrograde pyelogram.

The investigators reported that operative time and warm ischemia time were significantly reduced in the BioGlue group, compared with the control group. In addition, the Crosseal group showed a trend toward shorter operative time and warm ischemia time than the control group. However, the complication rate in the Crosseal group was higher than that of both the control and BioGlue groups.

Mean operative time in the control group was 115 minutes, compared with 96 minutes in the Crosseal group (p=.129) and 77 minutes in the BioGlue group (p=.014). Mean warm ischemia time was 34.6 minutes in the control group, compared with 26.6 minutes in the Crosseal group (p=.117) and 17.4 minutes in the BioGlue group (p<.001).

Two swine in the Crosseal group had a hematoma, compared with none in the control or BioGlue groups. One swine in the control group and three in the Crosseal group had a urinoma, compared with none in the BioGlue group. Urine leakage was observed in a majority of animals in all groups (three control, three BioGlue, and four Crosseal recipients).

"This study provides insight into the steps being made to assist the urologist in adjunctive measures for repair and sealing of collecting system defects, but more experimental studies are needed to better delineate the most efficacious agent with the least potential side effects," Dr. Springhart said.

Funding for the animal research was provided by CryoLife, Inc.