Decision Making in Urethral Trauma

Is the cause of urethral trauma similar in dogs and cats?
Road accident/pelvic trauma is the most common cause in dogs whereas traumatic urethral catheterisation in obstructed cats is common. In a study of 63 cats with urethral rupture the cause was trauma in 55% and iatrogenic in 45%. In dogs, the majority of urethral injuries presenting with concurrent pelvic fractures, whereas only 37% of trauma cases cats have concurrent pelvic fractures, indicating that blunt trauma without pelvic fractures can commonly lead to significant urethral injury in cats. All cats with iatrogenic injury only suffered a partial urethral rupture, whereas only 3/13 cats (23%) in the trauma group has a partial injury

Does the timing of imaging studies, temporary surgery/urinary diversion and definitive surgery affect outcome?
The only prognostic factor in a series of dogs and cats with urethral rupture was the presence of multiple traumatic injuries i.e. the urethral injury itself was not the limiting factor. Initial clinicopathologic findings and time to surgery were not prognostic factors. Another series of cats with traumatic uroperitoneum also concluded that morbidity and mortality depends on the severity of associated injuries rather than the urinary tract injuries. A study of 63 cats with urethral rupture found that those due to trauma were more likely to have concurrent musculoskeletal injury (not necessarily pelvic fractures) and less likely to survive to discharge (57% v 86%). Significant wounds did develop in association with uraemic cellulitis. It is important to prioritise any other life-threatening injuries, whilst instituting urinary diversion and stabilisation to address the consequences of urine leakage which itself does not require immediate definitive surgical correction. In some unstable patients urinary diversion may be instituted before contrast imaging studies and a precise location for the urethral/urinary tract rupture is known. A minimally invasive inguinal approach for tube cystotostomy has been described. A definitive surgical/treatment plan is made when the patient is stable and appropriate contrast imaging studies have been performed. Partial injuries in humans are treated with an indwelling catheter for 2-4 weeks and it has been suggested that any primary urethral repair should be performed at least 7-10 days after trauma at which point haemorrhage will have stabilised and the elasticity of the urethral tissues is still sufficient, and more recently there has been a shift towards delayed urethroplasty (3-6 months suprapubic urinary diversion) or early endoscopic re-alignment. However the management of urethral ruptures in humans is influenced not only by stricture formation but also by the high impotence and urinary incontinence rate post immediate primary repair, which is not reported in cats and dogs.  [...]