Kidney and Urinary Tract Disease - Test of Renal Function Flashcards Preview

Clinical Pathology > Kidney and Urinary Tract Disease - Test of Renal Function > Flashcards

Flashcards in Kidney and Urinary Tract Disease - Test of Renal Function Deck (44):
1

Kidney function

Excretion (uric acid), regulation (homeostasis, water, acid base), endocrine (renin, erythropoietin)

2

Kidney function

Excretion (uric acid), regulation (homeostasis, water, acid base), endocrine (renin, erythropoietin)

3

Urine volume

750-2000ml/24hr

4

Oliguria

5

Anuria

6

Polyuria

>3000

7

Plasma urea

Quick, simple measurement, 3-8mmol/L (sensitive)

8

Urea excretion

Filtered at glomerulus, 40% reabsorbed, if slow tubular flow more reabsorbed (renal hypo perfusion)

9

Causes of increased plasma urea

GI bleed, trauma, renal hypo perfusion (decreased RBF, ECFV), acute renal impairment, chronic renal disease, post-renal obstruction calculus tumour

10

Urea

Useful, must be interpreted with great care, always consider input, out and patient's fluid volume

11

Plasma creatinine

50-140umol/L, increases in conc as GFR decreases (NOT proportional to renal damage)

12

Creatine clearance

Ucreat X V/Pcreat

[RR 100-130 mL/min]
(incomplete collection/unreliable)

13

Tubular secretion of creatine

Increased in chronic renal disease and decreased by drugs (salicylate, cimetidine)

14

Pre-renal oliguria

GFR reduced, ADH increased, renal hypo perfusion causes renin secretion (increase Na reabsorption)

15

Low renal perfusion caused by

Dehydration, haemorrhage, renal artery damage, hypotension

16

Renal oliguria

GFR reduced/normal, weak urine/low volume, renal renin secretion may be raised (hypertension, unable reabsorb Na)

17

Intrinsic damage causing renal oliguria

Tubular necorsis, chronic infection, immunological damage (SLE), toxic damage (drugs, heavy metals Hg, Ur, poisons)

18

Lab tests of renal function

plasma creatinine
plasma urea
plasma sodium
urine volume
urine sodium
urine urea
creatinine clearance
urine dispsticks

19

Problem with GFR

Impractical

20

Problem with CC

Unreliable

21

Problem with plasma creatine

Specific, but insensitive

22

Problem with plasma urea

Subject to problems

23

Problem with urine vol

Often forgotten

24

Urine volume

750-2000ml/24hr

25

Oliguria

26

Anuria

27

Polyuria

>3000

28

Plasma urea

Quick, simple measurement, 3-8mmol/L (sensitive)

29

Urea excretion

Filtered at glomerulus, 40% reabsorbed, if slow tubular flow more reabsorbed (renal hypo perfusion)

30

Causes of increased plasma urea

GI bleed, trauma, renal hypo perfusion (decreased RBF, ECFV), acute renal impairment, chronic renal disease, post-renal obstruction calculus tumour

31

Urea

Useful, must be interpreted with great care, always consider input, out and patient's fluid volume

32

Plasma creatinine

50-140umol/L, increases in conc as GFR decreases (NOT proportional to renal damage)

33

Creatine clearance

Ucreat X V/Pcreat

[RR 100-130 mL/min]
(incomplete collection/unreliable)

34

Tubular secretion of creatine

Increased in chronic renal disease and decreased by drugs (salicylate, cimetidine)

35

Pre-renal oliguria

GFR reduced, ADH increased, renal hypo perfusion causes renin secretion (increase Na reabsorption)

36

Low renal perfusion caused by

Dehydration, haemorrhage, renal artery damage, hypotension

37

Renal oliguria

GFR reduced/normal, weak urine/low volume, renal renin secretion may be raised (hypertension, unable reabsorb Na)

38

Intrinsic damage causing renal oliguria

Tubular necorsis, chronic infection, immunological damage (SLE), toxic damage (drugs, heavy metals Hg, Ur, poisons)

39

Lab tests of renal function

plasma creatinine
plasma urea
plasma sodium
urine volume
urine sodium
urine urea
creatinine clearance
urine dispsticks

40

Problem with GFR

Impractical

41

Problem with CC

Unreliable

42

Problem with plasma creatine

Specific, but insensitive

43

Problem with plasma urea

Subject to problems

44

Problem with urine vol

Often forgotten

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