Does topical haemostatic agent have an adverse effect on the function of the prostatic neurovascular bundle?

To assess the functional and histological effects of a bovine thrombin topical haemostatic agent used clinically to aid in surgical haemostasis (FloSeal(TM), Baxter International Inc., Deerfield, IL, USA) on the cavernous nerves in a canine model of survival, as there are concerns that the fibrotic/inflammatory response to this product could affect neural function.

In phase I, nine adult male dogs had the bilateral neurovascular bundles (NVBs) dissected. A small intravenous catheter placed directly into the erectile bodies of the penis was used to record the intracorporal pressure (ICP). Erection was induced by electrical stimulation of the NVB on each side. After intraoperative randomization to treatment or control, 5 mL of FloSeal was unilaterally applied along the NVB on the treatment side. In phase II, after 2 weeks of survival, both control and treatment NVB were again dissected and re-stimulated to produce an erectile response. The mean arterial pressure and ICP were recorded. The prostate and the NVBs were then removed for histological analysis.

All dogs achieved erections after electrical stimulation on both the control and treatment side. There was no statistically significant difference in absolute ICP, pressure increase from baseline or systemic pressure after stimulating the NVB on the treatment side between phases I and II. Histological analysis showed a giant-cell reaction around the FloSeal granules and mild focal perineural oedema, but the cavernous nerves were otherwise normal in appearance.

In this short-term functional study, FloSeal did not adversely affect cavernous nerve function, measured as the erectile response to electrical stimulation. We found no evidence contraindicating its use during radical prostatectomy.