Chapter 175 - Hemodialysis introduction

Question 1

1997 National Kidney Foundation - Dialysis Outcome Quality Initiative key point

Answer 1

Autogenous AV access first
Early detection of dysfunction before thrombosis

Goal of 50% fistula first
40% current HD patients

Question 2

Fistula first breakthrough initiative

Answer 2

Put forward in 2005 KDOQI

reached 60% prevalence in 2011

Question 3

Fistula first catheter last workgroup coalition goal

Answer 3

1) increase autogenous AV acces to 68%
2) decrease long term catheter > 90 days to 10%

Difference is to go to prosthetic access early if autogenous unlikely

Question 4

SVS guidelines targeted 7 areas

Answer 4

1) timing of referral to access surgeon
2) operative strategy to maximize placement of autogenous AV access
3) first choice for autogenous access
4) choice of AV access when patient not suitable for forearm
5) role of monitoring and surveillance
6) conversion of prosthetic AV access to secondary autogenous AV access
7) management of nonfunctional or failed av ACCESS

Question 5

Timing of referral for permanent dialysis access

Answer 5

1) CrCl < 25
2) > 6 months before anticipated HD
3) if prosthetic use then delay until 3-6 weeks prior to dialysis

Question 6

Current rate of fistula first in new dialysis patients

Answer 6

25%

Question 7

Real life reasons for starting dialysis with catheter

Answer 7

1) inadequate predialysis care 45%
2) AKI failure to recover 31%
3) noncompliance of patient with appointments 17%

Question 8

H&P for pre-op access

Answer 8

1) dominant extremity
2) recent peripheral IV
3) previous CVC and PM and defibrillator
4) previous access procedure
5) previous trauma or surgery

PEx

1) arterial: brachial, radial, ulnar
2) Allen test
3) superficial venous system mapping +/- tourniquet

Question 9

Factors that worsen patency

Answer 9

1) age
2) DM
3) atherosclerosis
4) smoking
5) parathyroid hormone
6) anemia
7) some medications (no consensus)

Question 10

Factors that do not affect patency

Answer 10

Sex

Obesity

Question 11

Lazarides metaanalysis on elderly whats best first access key points

Answer 11

1) age 50-70
2) RC AVF patency poor than younger patients
3) BC AVF > RC AVF patency
4) prosthetic access just as good

Recommend BC AVF > prosthetic > RC AVF

Question 12

Diabetes on fistula maturation rate

Answer 12

1) increase failure
2) increase risk of steal

Suggest using distal artery to avoid steal

Question 13

Arterial characteristic for adequate AVF inflow

Answer 13

1) no pressure gradient between two arms
2) artery > 2 mm
3) patent palmar arch

Question 14

Success rate based on vein diameter

Answer 14

2mm 76%
2.5 mm 92%
3 mm 90%

Question 15

Snuffbox fistula define

Answer 15

posterior radial branch - cephalic wrist access

Question 16

Another name for racial-cephalic fistula

Answer 16

Brescia-Cimino-Appel fistula

Question 17

General sequence of access site and type selection

Answer 17

1) UE access first in non-dominant arm
2) As far distally as possible
3 Autogenous before prosthetic
4) Direct AV best > venous transposition > venous translocation

Question 18

Arteriotomy size for fistula anastomosis

Answer 18

4-6 mm

Question 19

Two stage procedure duration of wait

Answer 19

4-6 weeks

Question 20

Vein sizes that may be more suitable for single stage rather than 2 stage creation

Answer 20

> 4 mm

Question 21

Timing of cannulating standard wall grafts in AVG

Answer 21

2 weeks

Question 22

Early cannulation prosthetic graft

name
manufacturer
composition
time to cannulate

Answer 22

Acuseal (Gore)
24 hour to cannulation

3 layers: elastomeric membrane between two layer of ePTFE

Question 23

BAM procedure

Answer 23

Balloon-assisted maturation of fistula

repeated ballooning turning vein into a collagen tube

similar patency as prosthetic conduits

Question 24

Method of monitoring access flow

Answer 24

1) ultrasound dilution
2) conductance dilution
3) thermal dilution
4) Doppler technique

Question 25

Access flow numbers to prompt further investigation

Answer 25

1) < 600 ml/min

2) < 1000 ml/min and 25% decrease over 4 months

Question 26

Static venous dialysis pressure values that prompt further investigation in AVG

Answer 26

1) graft-arterial ratio > 0.75
2) graft venous ratio < 0.5
3) progressive increase in venous or arterial segment > 0.25

Question 27

Committee on reporting standards of the SVS on AV access patency

Answer 27

1) flow rate 350-400 ml/min
2) no access recirculation
3) dialysis time < 4 hours

Question 28

Definition of primary patency, assisted primary patency and secondary patency in AV access

Answer 28

Primary patency: no intervention
Assisted primary: endo or surgical intervention without thrombosis
Secondary patency: intervention including thrombosed graft thats brought back

Question 29

Primary patency of autogenous vs prosthetic access

Answer 29

1 year
AVF: 43-85%
AVG 40-54%

2 year
AVF: 40-69%
AVG: 18-30%

Question 30

Secondary patency of autogenous vs prosthetic access

Answer 30

1 year
AVF 46-90%
AVG 59-65%

2 year
AVF 62-75%
AVG 40-60%

Question 31

Basilic vein vs prosthetic

Answer 31

Basilic better patency with 1 stage or two stage techniques

Question 32

Initial success of autogenous AVF rate

Answer 32

55-97%