Urinary Diversion

Question 1

What are relative contraindications for orthotopic neobladder?

Answer 1

Positive urethral margin, poor dexterity, male urethral stricture, Cr >1.8, gross positive margins, pubic bone involvement, hepatic insufficiency, IBD, malignant bowel disease

Question 2

What is an absolute contraindication to orthotopic ileal diversion?

Answer 2

Positive urethral margin on frozen intraop

Question 3

What is the most accurate way of measuring renal function with an ileal conduit? Why?

Answer 3

Fraction of excreted sodium since sodium absorption markedly unaffected in comparison to Cr and urea

Question 4

What renal function parameter is relatively unaffected after urinary diversion w/ bowel?

Answer 4

fraction of excreted sodium.

B/c ammonium is used instead of sodium in the Na/H anti porter

Question 5

What are the benefits to using colon over ileum?

Answer 5

Less likely to obstruct
Reaches easily to anywhere in the pelvis
Less nutritional problems

Question 6

For those w/ Cr of 2, what criteria must be met to proceed with orthotropic neobladder?

Answer 6

GFR > 35
urinary pH of 5.8 after ammonium challenge
osmolality of 600 w/ water deprivation