Chapter 126 - Renovascular disease open surgical treatment

Question 1

First definition on the causal relationship between RVD and HTN

Answer 1

1934 Goldblatt

Question 2

Historical timeline of renovascular disease treatment

Answer 2

FIGURE 126.1

Question 3

Factors favoring recovery of renal function after open treatment of RAS

Answer 3

1) severe HTN 2) bilateral/global atherosclerotic renovascular disease (>90% stenosis) 3) rapidly deteriorating renal function before surgery if these features exist, surgery can remove 70% of patients from dialysis

Question 4

General guidelines for RAS open repair

Answer 4

1) severe one side, mild the other, treat as unilateral lesion 2) bilateral moderate 60-80% then treat if HTN severe 3) bilateral severe > 80% then treat bilateral revasc

Question 5

Prerequisite of renal artery intervention

Answer 5

Severe HTN

Question 6

open renal repair advocated in these select patients

Answer 6

1) children with hypoplastic lesions 2) adults with dysplastic lesions not medial fibroplasia 3) FMD with aneurysm 4) atherosclerotic lesions in good risk < 65yr

Question 7

Dose of mannitol for aortic/renal dissection

Answer 7

12.5g given early additional dose up to 1g/kg possible

Question 8

Meandering mesenteric vessel

Answer 8

Arc of Riolan SMA –> middle colic –> left colic –> IMA

Question 9

Open techniques for reconstructing renal artery

Answer 9

1) Aortorenal bypass 2) renal artery thromboendarterectomy 3) renal artery reimplantation

Question 10

Length of arteriotomy in renal artery bypass

Answer 10

3x of the renal artery diameter

Question 11

Conduit for aorto-renal bypass

Answer 11

GSV, PTFE 6mm, IIA renal artery at least 4mm

Question 12

Thromboendarterectomy of renal artery

Answer 12

Typically via transaortic approach Eversion endarterectomy of renals

Question 13

Other inflow options for renal bypass

Answer 13

1) Hepato renal bypass 2) splenorenal bypass 3) ex vivo reconstruction

Question 14

Hepatorenal bypass key points

Answer 14

1) Subcostal incision 2) enter lesser sac 3) hepatic artery around GDA isolated 4) Kocher maneuver to mobilize descending duodenum 5) IVC identified along with right renal vein 6) right renal artery exposed immediately behind renal vein 7) route bypass via foramen of Winslow

Question 15

Splenorenal bypass key points

Answer 15

1) left subcostal or midline incision 2) posterior pancreas mobilized to develop retropancreatic plane 3) splenic artery mobilized from left GEA to terminal branches 4) left renal artery exposed by dividing adrenal vein 5) splenic artery used as conduit or GSV bypass

Question 16

Renal protection should occur if more than this amount of time of ischemia anticipated

Answer 16

40 min

Question 17

Renal protection

Answer 17

1) surface cooling 2) hypothermic perfusion 3) topical ice slush 4) mannitol

Question 18

Exvivo reconstruction steps

Answer 18

1) extended flank incision from midline to posterior axillary line 2) Gerota’s fascia opened with cruciate incision 3) kidney mobilized and vessels divided 4) ice slush (good for 2-3 hours) 5) flush kidney with 300-500 ml until effluent is clear

Question 19

Reasons to use iliac fossa as site of renal transplant

Answer 19

1) reduction in magnitude of exposure 2) manual palpation of transplanted kidney 3) ease in removal not applicable in autotransplantation

Question 20

reasons to not autotransplant kidney to iliac fossa

Answer 20

1) makes future aortoiliac intervention more difficult 2) question on patency in cases of worsening atherosclerosis

Question 21

Intraoperative duplex sonography sensitivity and specificity to detect technical problems

Answer 21

Sensitivity 86% Specificity 100%

Question 22

Appearance of acute venous thrombus and acute arterial platelet aggregate on duplex

Answer 22

Venous thrombus = echolucent Arterial platelet = irregular echogenic

Question 23

Post-operative stenosis/thrombosis rate after open bypass

Answer 23

3.3%

Question 24

Recurrent HTN and declining renal function after open bypass

Answer 24

3.7%

Question 25

Followup restenosis after open bypass in 22 months

Answer 25

3.4%

Question 26

Operative morbidity and mortality after open renal artery reconstruction

Answer 26

Morbidity 15-20% Dialysis dependence <1% Mortality 0.8% unilateral; 1.6% bilateral; 3.3% combined with aortic work; 6.9% when visceral and aortic work combined

Question 27

Improvement with renal function following repair

Answer 27

58% 70% removed from permanent dialysis

Question 28

Blood pressure improvement following renal reconstruction

Answer 28

85% improved 15% no improvement

Question 29

Factors associated with death or dialysis

Answer 29

Pre-op 1) DM 2) severe aortic occlusive disease 3) poor renal function Post-op 1) level of BP improvement 2) level of renal function improvement

Question 30

Consequence of failed open renal artery repair

Answer 30

Needing reoperation or nephrectomy RISK of dialysis dependence 12.6x RISK of reduced dialysis-free survival 2.4x