A retrospective analysis of clinical features, management and outcomes in dogs and cats with Eastern Brown Snake envenomation (2016–2022)

Australian Eastern brown snakes (Pseudonaja textilis) can cause venom-induced consumptive coagulopathy (VICC) in envenomated dogs and cats due to toxin-induced consumption of clotting factors. The objective of this study was to describe presenting clinical signs, prevalence of VICC and haemorrhage, VICC resolution timelines and patient outcomes in a population of dogs and cats with Eastern brown snake envenomation (EBSE). Data from dogs and cats presenting with EBSE were retrospectively evaluated. Univariable and multivariable analyses were performed to test predictor variable effects on outcomes. Animals who were euthanased for financial reasons on presentation were excluded from treatment and outcome analysis. Two-hundred and forty dogs and 98 cats were included. On presentation, 66% (159/240) of dogs had lower motor neuropathy (LMN), 31% (74/240) had preparalytic collapse and 30% (72/240) had signs of haemorrhage. In cats, 94% (92/98) had LMN, and only 5% (5/98) had haemorrhage. Ninety-two percent of dogs (209/226) and cats (81/88) were diagnosed with VICC on presentation and median time to normalisation of coagulation tests was 24 hours. Median hospitalisation length was 1.5 days for dogs (lower quartile [LQ]-upper quartile [UQ]: 1.0-3.0) and 2 days for cats (LQ - UQ: 1.0-2.5). Dogs presenting with LMN and no history of preparalytic collapse had significantly longer hospitalisation times (median 2.25 vs. 1.0 days, P-value <0.001; median 2.0 vs. 1.0 days, P-value <0.001 respectively). Odds of survival was lower in dogs with LMN (odds ratio [OR]: 0.23) and in the pooled multivariable analysis of dogs and cats with haemorrhage (OR: 0.39). The administration of antivenom overall was found to confer a survival advantage; however analysis failed to show increased odds of survival with administration of more than 4000 units. Overall, 89% (187/210) of dogs and 75% (58/77) of cats survived to discharge.