Chapter 116: Bladder Flashcards
The lateral ligaments of the bladder attach the bladder to the pelvic walls. What do they contain?
Fat, the distal portion of each ureter, and the umbilical artery on each side.
Which nerve innervates the vesicourethral junction to keep it in a constant state of contraction, except at micturition?
The hypogastric nerve (from TL spine) via alpha receptors
sympathetic = store IMPORTANT
Which nerve innervates the periurethral striated muscle at the bladder neck - a.k.a. the external urethral sphincter?
The pudendal nerve (spinal nerves S1-S3)
Parasympathetic = pee IMPORTANT
Which artery is the major blood supply to the bladder?
Caudal vesicular artery (arising from vaginal or prostatic branch of the internal pudendal artery) IMPORTANT
Cranial vesicular may supply the cranial bladder.
What veins drain the bladder?
Internal pudendal veins
How many days does it take for a mucosal defect in the bladder to heal?
How many days to 100% normal tissue strength?
5 days
14-21 days to 100%
What is the infection rate for cystotomies when there is no concurrent UTI?
5%
How much of the bladder can feasibly be removed with cystectomy?
40-70% (depends on ureteral locations).
Why is it important to keep trigone of the bladder intact when performing cystectomy?
Leaving the trigone intact is important for regeneration of bladder mucosa because the cells arise from epithelium of the terminal ureters and urethra (in the trigone).
uroabdomen is a complication from cystotomy in what % of cases?
1.5%
What layer of the bladder wall is the strength-holding layer?
Submucosal
What is the best suture to use in the bladder?
What size and needle type?
Absorbable monofilament - less drag and bacterial adherence.
A study evaluating the tensile strengths of four monofilament suture materials found that while PDS and polyglyconate (maxon) are OK, poliglecaprone 25 (monocryl) may not have sufficient tensile strength during the critical phase of bladder healing in E. coli urine.
Voluntary control of micturition occurs via what pathway?
Pudendal nerve control of striated urethral muscle and direct cortical innervation of the pontine micturition center.
How is micturition stimulated?
When the bladder nears capacity, the distention of detrusor mm. activates stretch receptors -> parasympathetic stimulation -> reflex contraction of detrusor. Stretch receptors also lead to depression of sympathetic outflow and acts on the brainstem (pontine center) to cause relaxation of smooth/striated urethral muscles.
* integration of the brainstem is needed to sustain detrusor contraction long enough to void.
Parasympathetic = pee
What are three “P”s involved?
Pelvic nerve (S1-S3)
Pudendal nerve (S1-S3)
Pontine micturition center (Pons, brainstem)
Sympathetic = store
What is the non-s nerve (and it’s A and B receptors) that helps store urine?
Hypogastric nerve (TL spine)
Keeps smooth muscle tight with alpha receptors
Relaxes the detrusor with Beta receptors
What lymphatics drain the bladder?
hypogastric and sublumbar LN
What are the three parts of the bladder?
Apex
Body
Neck
What suture materials are most appropriate for use in the bladder?
What organism disintegrated all tested sutures by day 7?
- Polydioxanone and polyglyconate
- Proteus mirabilis
The ventral medial ligament connects the bladder to the linea and pubic symphysis. In fetuses, what else runs through here?
Urachus
What are the layers of the bladder wall?
Urothelium (mucosa (transitional cells) and submucosa connective tissue)
Detrusor muscle (smooth, with oblique, interdigitating fibers)
Serosa
Is there an anatomically distinct internal urethral sphincter?
NO
Urethral muscle is continuous with the detrusor.
Where does all bladder innervation merge before entering the bladder at the neck?
The pelvic plexus
What effect does azotemia have on anesthesia and surgery?
Alterations of pharmacokinetics of drugs and of animal’s sensitivity to those drugs.
Interferes with platelet function (check BMBT)
What are the effects of hyperkalemia on anesthesia?
Bradycardia
Arrhythmias
Potentiates the cardio-depressant effects of anesthetic drugs. ** Correct it before surgery**
How do you correct hyperkalemia in a urinary patient?
Fluid therapy, decompressive cysto or urinary diversion, peritoneal drainage, calcium gluconate, insulin+glucose, bicarbonate administration
What antibiotics are a reasonable choice for perioperative antibiosis in bladder surgery?
Clavamox
3rd generation cephalosporins
(Broad-spectrum, bactericidal, non-nephrotoxic)
Give at induction then q2hr intraop, don’t continue unless infected (will not affect any cultures taken)
What are good choices for oral empiric antibiotics in bladder procedures while culture is pending?
Clavamox, 3rd gen cephalosporins, enrofloxacin
Suture-associated recurrent urolithiasis was reported in one study in what % of cases?
9.4% dogs, 4% cats but was retrospective, materials used were not reported.
In general, avoid nonabsorbables and try to avoid penetrating mucosa.
What are principles of surgery for the bladder?
Gentle handling: stay sutures, moistened swabs, suction instead of swabs, keep everything moist, avoid cautery.
You may need an abdominal retractor - Tobias says the Gosset.
What is different between a Balfour and Gosset retractor?
The Gosset retractor functions similarly to the Balfour retractor, but it is generally smaller and does not have a central blade)
When should you use NSAIDs in a urinary surgery case?
Withold until normovolemic and eating / of course don’t use in renal failure.
What is normal urine output in small animals?
1-2 mL/kg/hour
