Inefficacy of Dilute Epinephrine in Preventing Feline Scrotal Hematomas: Results From a Randomized Control Trial




feline medicine, TNR, trap-neuter-return, scrotal hematoma, epinephrine, hematoma, community cats, preventative medicine


Introduction: The authors previously investigated using epinephrine at 1:400,000 dilution to prevent scrotal hematoma but found no significant reduction in hematomas. We hypothesized that higher concentrations of epinephrine would reduce the incidence of hematomas.

Methods: Male cats trapped for Midwestern University College of Veterinary Medicine’s Trap-Neuter-Return program were assigned to one of three treatment groups in this randomized control trial: LRS control (A), 1:40,000 epinephrine (B), or 1:120,000 epinephrine (C). Each patient received 0.2 mL of treatment as a topical wash within the scrotum. Veterinarians blinded to the treatment group assessed for the presence and severity of hematoma at three stages.

Results: 398 cats were enrolled into groups A (n = 136), B (n = 133), and C (n = 129). Number of hematomas occurring in each group were 15 (11%, 95% confidence interval [CI]: 6–18%), 12 (9%, 95% CI: 5–15%), and 8 (6%, 95% CI: 3–12%), respectively. There was no difference in the incidence of scrotal hematoma (P = 0.397) or scrotal hematoma requiring treatment (P = 1.0). Weight was the only variable associated with the risk of hematoma (odds ratio [OR]: 7.3; 95% CI: 3.9–13.9; P < 0.0001).

Conclusion: Despite its vasoconstrictive effects, dilute epinephrine as a topical wash was ineffective in preventing feline scrotal hematomas.


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Pollari FL, Bonnett BN. Evaluation of postoperative complications following elective surgeries of dogs and cats at private practices using computer records. Can Vet J. 1996;37(11):672–678.

Kreisler RE, Harder KN, Douglas ML, Norris JW. Assessment of dilute epinephrine and mechanical pressure for prevention of feline postoperative scrotal hematoma: a randomized controlled trial. Top Companion Anim Med. 2022;46:100609. doi:10.1016/j.tcam.2021.100609

Leslie G, McPhee D. Adrenaline necrosis. Br Med J. 1953;1(4823):1315–1316. doi:10.1136/bmj.1.4823.1315

Aycock BG, Hawtof DB, Moody SB. Treatment of peripheral ischemia secondary to lidocaine containing epinephrine. Ann Plast Surg. 1989;23(1):27–30. doi:10.1097/00000637-198907000-00005

Denkler K. A comprehensive review of epinephrine in the finger: to do or not to do. Plast Reconstr Surg. 2001;108(1): 114–124. doi:10.1097/00006534-200107000-00017

Krunic AL, Wang LC, Soltani K, Weitzul S, Taylor RS. Digital anesthesia with epinephrine: an old myth revisited. J Am Acad Dermatol. 2004;51(5):755–759. doi:10.1016/j.jaad.2004.05.028

Finsen V. Nekrose i fingre og tær etter lokalbedøvelse med adrenalin – en vandrehistorie? [Necrosis in fingers and toes following local anesthesia with adrenaline – an urban legend?] Tidsskrift for den Norske Lægeforening. 2013;133(17): 1827–1830. doi:10.4045/tidsskr.13.0373

Chow Y-C, Yang S, Huang C-J, et al. Epinephrine promotes hemostasis in rats with cyclophosphamide-induced hemorrhagic cystitis. Urology. 2006;67(3):636–641. doi:10.1016/j.urology.2005.10.003

Sheikh R, Dahlstrand U, Memarzadeh K, Blohmé J, Reistad N, Malmsjö M. Optimal epinephrine concentration and time delay to minimize perfusion in eyelid surgery: measured by laser-based methods and a novel form of extended-wavelength diffuse reflectance spectroscopy. Ophthalmic Plast Reconstr Surg. 2018;34(2):123–129. doi:10.1097/IOP.0000000000000883

Whittle TJ, Sugawa C, Lucas CE, et al. Effect of hemostatic agents in canine gastric serosal blood vessels. Gastrointest Endosc. 1991;37(3):305–309. doi:10.1016/S0016-5107(91)70720-7

Millard H. Veterinary Surgery Chapter 111. 2nd ed. Saint-Louis, MI: Elsevier Health Sciences; 2017.

Kreisler RE, Shaver SL, Holmes JH. Outcomes of elective gonadectomy procedures performed on dogs and cats by veterinary students and shelter veterinarians in a shelter environment. J Am Vet Med Assoc. 2018 Nov 15;253(10): 1294–1299. doi:10.2460/javma.253.10.1294



How to Cite

Vitello, E., Sheffer, S., Norris, J., & Kreisler, R. (2024). Inefficacy of Dilute Epinephrine in Preventing Feline Scrotal Hematomas: Results From a Randomized Control Trial. Journal of Shelter Medicine and Community Animal Health, 3(1).



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