Chapter 129 - Renovascular disease acute occlusive and ischemic events

Question 1

Renal ischemic injury mechanism

Answer 1

Glomerular collapse + tubular necrosis –> reduced glomerular filtration –> loss of tubular function

Question 2

Reperfusion renal injury

Answer 2

Endothelial dysfunction –> excess cytokine secretion –> leukocyte influx

Excessive NO and ROS –> parenchymal damage

Question 3

1 hour warm ischemia associated with this much renal function loss
how much recovery is expected?

Answer 3

70-80%

Complete recovery within weeks

Question 4

2 hours warm ischemia time how much recovery is expected

Answer 4

30-50%

Question 5

Collaterals of the renal artery

Answer 5

1) inferior adrenal
2) gonadal
3) ureteral
4) internal iliac
5) lumbar
6) intercostal
7) capsular arteries
8) IMA

Question 6

Prevalence of assessory/aberrant or duplicate renal arteries

Answer 6

24-42%

Question 7

Symptoms of acute renal ischemia

Answer 7

1) abdominal/back pain
2) dyspnea
3) nausea vomiting
4) hematuria
5) anuria
6) acute HTN

Question 8

Differential diagnosis to acute renal ischemia

Answer 8

1) pyelonephritis
2) renal carcinoma
3) mesenteric ischemia
4) cholecystitis
5) biliary colic
6) gastritis
7) splenic infarction
8) myocardial infarction
9) pulmonary embolism

Question 9

Classic triad of renal vein thrombosis

Answer 9

1) flank mass
2) gross hematuria
3) thrombocytopenia

only in 13% of neonates with renal vein thrombosis

Question 10

Lab findings of acute renal ischemia

Answer 10

1) leukocytosis
2) elevated LDH
3) microscopic/gross hematuria
4) proteinuria
5) elevated D-dimer
6) eosinophilia (atheroembolism)

Question 11

does normal Cr rule out renal ischemia

Answer 11

no, contralateral kidney may still function well

Question 12

CTA sensitivity for renal ischemia

Answer 12

80%

Question 13

CTA sen and spe for renal vein thrombosis

Answer 13

100%; 100%

Question 14

CTA finding on renal infarct

Answer 14

1) hypoattenuation with associated mass effect

2) cortical rim sign - rim of functioning nephrons from capsular collaterals

Question 15

US in renal artery ischemia

Answer 15

Only useful in detecting total occlusions

Otherwise poor sensitivity

Question 16

Nuclear scan in renal ischemia

Answer 16

97% sensitivity

Sign: Marked reduction of renal blood flow with preserved kidney size

Question 17

Renal artery embolism incidence in hospital

Answer 17

0.007%

Question 18

Risk factors of cholesterol crystal embolization

Answer 18

1) male
2) HTN
3) atherosclerosis
4) following arterial cath

Question 19

Cholesterol crystal embolization to kidney and association with dialysis in 2 years

Answer 19

30%

Question 20

Percentage of patients with renal artery embolism with previous thromboembolism

Answer 20

20%

Question 21

Outcome of renal artery embolization

Answer 21

11% death 1 month
61% return to normal
8% dialysis

Question 22

Mortality following surgical renal artery thrombectomy

Answer 22

25%

Question 23

Causes of renal artery thrombosis

Answer 23

1) atherosclerosis
2) aortic occlusion
3) aortic/renal dissection
4) renal aneurysm
5) FMD
6) Takayasu
7) stent thrombosis
8) hypercoagulable state
9) trauma
10) antiphospholipid antibody
11) factor V Leiden
12) HITT
13) Bechet

Question 24

Prevalence of renal artery atherosclerotic stenosis

Answer 24

7%

Question 25

5 year rate of thrombosis in pre-existing renal artery stenosis

Answer 25

5%

Question 26

Risk factors for progression to renal artery thrombosis

Answer 26

1) SBP > 160 2) DM 3) > 60% stenosis

Question 27

Factors associated with risks of spontaneous renal artery dissection

Answer 27

1) FMD 2) Ehlers-Danlos 3) cocaine use 4) strenuous exercise

Question 28

Success of endovascular treatment of renal artery thrombosis

Answer 28

70% technically successful 25% recover renal function

Question 29

Mortality after open surgical revasc for renal thrombosis salveage of renal function

Answer 29

15-25% mortality 65% salvage

Question 30

Mortality after renal artery trauma

Answer 30

21% usually due to associated injuries 10.3% mortality without other major organ injuries

Question 31

Kidney salvage rate in unilateral traumatic renal artery injury

Answer 31

25%

Question 32

Grade IV/V kidney injury predictors of poor outcome

Answer 32

1) blunt trauma 2) dialysis or Cr > 200 3) <25% remaining renal function of affected kidney 4) postinjury HTN

Question 33

Causes of renal vein thrombosis

Answer 33

1) malignancy (RCC, lymphoma, retroperitoneal tumor) 66% 2) nephrotic syndrome 20% 3) inherited thrombophilia 4) local surgery/inflammation 5) oral contraceptive use 6) pregnancy 7) infection 8) iatrogenic (IVC filter)

Question 34

Risk factors that precipitate renal vein thrombosis

Answer 34

1) CVC 2) dehydration 3) prolonged hypotension

Question 35

Risk of recurrent renal vein thrombosis

Answer 35

1%/year

Question 36

Mortality 6 months after acute renal vein thrombosis

Answer 36

40% largely due to malignancy and infection

Question 37

Survival advantage treatment for renal vein thrombosis

Answer 37

Warfarin therapy

Question 38

Indication for thrombectomy/thrombolysis in renal vein thrombosis

Answer 38

1) failure of oral anticoagulation (propagation, PE) 2) bilateral thrombosis 3) thrombosis of solitary kidney 4) caval thrombosis 5) acute renal failure 6) persistence of symptoms (flank pain)