Characteristics of Low-Speed Vehicular Rollover Trauma in Dogs Presenting to an Emergency Service at a Veterinary Teaching Hospital

Abstract

Objective: To describe the epidemiology of, and injuries associated with, low- versus higher-speed vehicular trauma and to identify risk factors associated with mortality. Design: Retrospective study from January 2015 to November 2020. Setting: University teaching hospital. Animals: A total of 150 dogs with low-speed (<20 mph) vehicular rollover (LSVRO) trauma and 272 dogs with other vehicular trauma (hit by car [HBC]). Interventions: None. Measurements and Main Results: Eighty-five percent of vehicles causing LSVRO trauma were driven by owners or family members of the dogs. Dogs in the LSVRO group were older (median: 4 vs. 2 years, p = 0.001), smaller (median weight: 11 vs. 21.5 kg, p = 0.001), and more often female (53.3% vs. 40.1%, p = 0.005) than the HBC group. Pelvic fractures, sacroiliac luxation, prepubic tendon rupture, and vertebral fractures were more common in the LSVRO group, and more soft tissue surgical procedures were required than in the HBC group (18.0% vs. 8.85%, p = 0.02). Within the LSVRO group, abdominal injuries (e.g., abdominal hernia, prepubic tendon rupture), pelvic fractures, and traumatic brain injury were all associated with increased mortality. Surviving dogs had higher ionized calcium concentration (1.26 ± 0.1 mmol/L) than those that died (1.18 ± 0.1 mmol/L, p = 0.003). There was a 40% reduction in survival odds for every 1-point increase in animal trauma triage score (p < 0.001). Blood product requirement and each soft tissue surgery increased mortality by 98% (p < 0.001) and 74% (p = 0.001), respectively, while orthopedic surgery conferred a 25-fold increase in odds of survival (p < 0.001). Conclusions: LSVRO trauma is characterized by a specific constellation of injuries compared with HBC trauma. Veterinary practitioners should be aware of the differences between the two trauma types and focus triage, resuscitation, and diagnostic tests in dogs with LSVRO trauma accordingly.