Renal Insufficiency

Question 1

What can cause renal insufficiency

Answer 1

disease
drugs
age

Question 2

What factors alter creatinine clearance

Answer 2

Sugars
Proteins
Cephalosporins
5-flucytosine
age, weight, gender
exercise
diurnal variation - lowest wake up
diet - meat increase
drugs

Question 3

What is cockloft-gault equation with creatinine clearance

Answer 3

Male:
(140-age) x (50 + (2.3 x ht over 5 ft))
—————————————————-
72 x SCr

Female:
(140 - age) x (45.5 + 2.3 * ht over 5 ft))
—————————————————— x .85
72 x SCr

Question 4

What is normal creatinine clearance

Answer 4

100 - 125 ml/min

Question 5

What is the effect of renal insufficiency on drug absorption

Answer 5

decreased gastric emptying and pH
Increased absorption
- dextropropoxyphene
- dihydrocodeine

Question 6

What is the effect of renal insufficiency on drug distribution

Answer 6

Changes in binding sites
decreased albumin concentrations
- acidic drugs decrease in plasma protein binding
- basic drugs inc/dec or normal plasma protein binding
measure unbound concentration for drugs with normal therapeutic range

Question 7

What is the effect of renal insufficiency on drug metabolism

Answer 7

Codeine/morphine - need smaller dose

meperidine - don’t use

Question 8

What is the effect of renal insufficiency on drug elimination

Answer 8

HR2 blockers dose can be smaller

aminoglycosides don’t get eliminated from body as eliminated via kidneys

Question 9

What factors affect ability of dialysis to clear drugs

Answer 9

molecular weight
water solubility
protein binding
volume of distribution
clearance