Urinary Incontinence and Retention: Intro and drugs for urinary retention Flashcards
What controls the bladder to allow the retention and storage of urine?
The sympathetic nervous system via spinal reflex loops and pontine control.
What is a spinal reflex loop?
Efferent outflow from hypogastric nerve stimulates beta-3 receptors (NE) which inhibits contraction of the detrussor and stimulates alpha-1 (NE) mediated contraction of the the internal urethral sphincter
What is the effect of the pontine storage center on the bladder control?
The pontine storage center sends neural signals through the pudendal nerve to stimulate nicotinic (Ach) receptors and cause contraction of the external urethral sphincter.
What causes micturation?
The parasympathetic nervous system inhibits the SNS to cause micturation
By what mechanisms does the PNS cause micturation?
Signals from the pariaqueductal grey matter inhibit the pontine storage center thus relaxing the urethral sphincter. Furthermore, the PNS causes firing of the pelvic nerves to stimulate the detrussor to contract via M3 (Ach) receptors
What is the typical treatment plan for urinary incontinence?
- Begins with non -invasive treatment
- Surgery and cath may sometimes be appropriate
- Add drugs when non-invasive treatment fails
What are the most common drugs used for urinary incontinence?
Antimuscarinics:
Tolterodine
oxybutinin
In what patient population must one be careful about giving anti muscarinics?
Elderly population (drug-drug interactions, cognitive impairment)
What are the adverse effects of anti-muscarinics?
SLUDGEBBB opposites S - dry mouth (most common)W L - Dry eyes U - Urine retention** D - Constipation G - E - B - Tachycardia B - B -
What are the contraindications for the anti-muscrinics?
Glaucoma
Urinary/GI obstruction
Alzheimer’s Disease
What is the main difference between oxybutinin and tolterodine?
For the most part they are the same except tolterodine has less of a chance of withdrawal and dry mouth.
How does Solifenacin compare to Tolterodine?
Solifenacin is better than Tolterodine b/c it has less dry mouth and less withdrawal.
How does Fesoterodine compare with Tolterodine?
Fesoterodine has less withdrawal symptoms than Tolterodine.
How are some anti-muscarinics altered to reduce dry mouth but maintain efficacy?
They are made in extended release formulations.
What drugs are used to treat urinary retention?
Bethanechol
Neostigmine
