POST-NEUTERING URETHRAL SPHINCTER MECHANISM INCOMPETENCE IN FEMALE DOGS

A castração de fêmeas caninas é uma cirurgia de rotina que visa principalmente a prevenção de doenças e o controle populacional da espécie. Ela não é, todavia, desprovida de consequências indesejáveis, e a incontinência urinária pós-castração é uma das mais significativas. Tratamento medicamentoso é preconizado para estes casos, sendo o emprego dos fármacos α-adrenérgicos e estrogênicos os mais frequentemente descritos na literatura. Entretanto, o uso de antidepressivos tricíclicos pode ser eficaz no controle dos sinais clínicos da incontinência. O mecanismo exato que envolve esta afecção ainda não é completamente entendido. Acredita-se que uma deficiência de estrógeno e consequente perda de tônus uretral sejam responsáveis pela ocorrência dos sinais, mas é possível que outros fatores como os níveis de gonadotrofinas e de hormônio liberador de gonadotrofinas estejam implicados na patogenia da incontinência urinária pós-castração.

Surgical treatment of refractory incontinence in the bitch

Urinary incontinence is a common condition in spayed, female dogs with a reported prevalence between 3.1% and 20.1%. In the majority of dogs with acquired urinary incontinence, urethral sphincter mechanism incompetence is the underlying cause. Approximately 15% of bitches that initially respond to medical therapy ultimately become refractory. Surgical intervention is indicated when patients do not respond or become refractory to medical treatment. Based on the current literature, placement of an artificial urethral sphincter, i.e. an inflatable cuff around the proximal urethra connected to a subcutaneous injection port, provides a very reliable and longterm incontinence resolution in bitches and has a low complication rate.

Medical treatment of urinary incontinence in the bitch

Urinary incontinence, an uncontrolled urine leakage during the storage phase of micturition, is a common condition in female dogs. In intact bitches, the reported prevalence is only 0.2-0.3%, but in spayed bitches it varies between 3.1-20.1%. Most commonly, dogs with acquired urinary incontinence suffer from urethral sphincter mechanism incompetence. This condition seems to be multifactorial, and although the exact pathophysiology remains unclear, potential risk factors include gender, gonadectomy, breed, body weight, urethral length and bladder neck position. In daily practice, the diagnosis of urethral sphincter mechanism incompetence is usually made after eliminating other potential causes of urinary incontinence. Incontinent bitches are primarily treated with medications, such as alpha-adrenergic drugs, e.g. phenylpropanolamine and oestrogens. Surgery is recommended when patients become refractory to medical treatment.

Medical treatment of urinary incontinence in the bitch

Urinary incontinence, an uncontrolled urine leakage during the storage phase of micturition, is a common condition in female dogs. In intact bitches, the reported prevalence is only 0.2-0.3%, but in spayed bitches it varies between 3.1-20.1%. Most commonly, dogs with acquired urinary incontinence suffer from urethral sphincter mechanism incompetence. This condition seems tobe multifactorial, and although the exact pathophysiology remains unclear, potential risk factors include gender, gonadectomy, breed, body weight, urethral length and bladder neck position. In daily practice, the diagnosis of urethral sphincter mechanism incompetence is usually made after eliminating other potential causes of urinary incontinence. Incontinent bitches are primarily treated with medications, such as alpha-adrenergic drugs, e.g. phenylpropanolamine and oestrogens. Surgery is recommended when patients become refractory to medical treatment.

Long-Term Outcome of Female Dogs Treated with Static Hydraulic Urethral Sphincter for Urethral Sphincter Mechanism Incompetence

ABSTRACT The purpose of the study was to report the postoperative outcome, complications, and long-term follow-up of the use of a static hydraulic urethral sphincter for the management of urethral sphincter mechanism incompetence in female dogs. Medical records were reviewed to extract information on long-term (>365 days) outcome data. Telephone owner questionnaire was performed to assess postoperative urinary continence scores (scale 1–10, where 10 is complete continence) and the presence and frequency of complications. Twenty female dogs were included. Mean (±standard deviation) time to follow-up was 1,205.1 (±627.4) days. Median continence score/10 (range) was 3.5 (2–6) preoperatively, and 9.0 (7–10) at the last follow-up. Median continence score was significantly higher at all time points postoperatively compared with before surgery (P < .001). Complete continence was achieved in 90% of bitches. Minor complications occurred in 13 bitches and included dysuria (8), bacterial cystitis (8), longer urination time (10), incisional seroma (5), urinary retention (3), hematuria (2), and pain when urinating (2). Major complications occurred in one dog (static hydraulic urethral sphincter removed 28 mo after placement). Continence scores were sustainably improved in the long-term. Complications were mostly minor. Urinary tract infections were the most common but resolved with conventional antibiotic treatment.