This document summarizes the history and developments in vascular access for hemodialysis. It discusses key milestones like the first hemodialysis in 1924, the Quinton-Scribner shunt in 1960, and the Brescia-Cimino fistula in 1966. It then compares arteriovenous fistulas, grafts, and catheters and their primary failure rates, infection risks, and longevity. The document outlines criteria for successful fistulas and grafts and factors that can lead to stenosis. It also discusses strategies to prevent stenosis and reduce catheter use, such as earlier patient referral and education on permanent access options.
6. Burdens in vascular access
Ivan D. Maya et al: AJKD 2008 (University of Alabama at Birmingham)
>20% of dialysis patients hospitalizations:
access related
Adjusted mortality: 40 ~ 70% greater for
catheter > AV shunt
Fistula prevalence: USA < Europe/Japan
75% of US patients initiate dialysis with a
catheter
7. Choices in vascular access
Ivan D. Maya et al: AJKD 2008(University of Alabama at Birmingham)
Feature Fistula Graft Catheter
Primary failure rate % 20 ~ 50 10 ~ 20 <5
Time to 1st use (W) 4 ~ 12 2~ 3
Immediate
Need to intervene VL Mod H
Qb Excel Excel Mod
Thrombosis rate VL Mod H
Infection rate VL Mod VH
Longevity ~ 5Y ~ 2Y <1Y
8. Vascular access monitoring
Ivan D. Maya et al: AJKD 2008(University of Alabama at Birmingham)
PE: absent thrill, abnormal bruit, distal
edema, pulsating swelling aneurysm (F) or
pseudo-aneurysm (G)
Dialysis abnormality: difficult puncture,
aspiration of clots, prolonged bleeding from
needle site
Unexplained decrease in Kt/V
9. Vascular access surveillance
Ivan D. Maya et al: AJKD 2008(University of Alabama at Birmingham)
Static dialysis venous pressure (DVP): Ratio of
DVP to systolic BP > 0.5: inaccurate predictor
Access blood flow: < 600mL/min(G) or <400-500
mL/min(F)
A decrease in Qa > 33% from baseline WD paulson et al: KI 81:
132-142, 2010
Doppler ultrasound: peak systolic velocity (PSV)
ratio > 2/1
Dynamic DVP and recirculation: less useful
Flow and change in flow(Qa and DVP) early in a
dialysis session by monthly flow surveillance:
inaccurate predictor
Sunanda et al: ALKD 52: 930-938, 2008 (N=176)
11. What is a successful fistula?
Allon et al, KI 62: 1109-24, 2002
Caliber large enough
Blood flow rate: access Qb > dialysis Qb by at least 100
ml/min to avoid vein collapse and re-circulation
mean dialysis Qb:
400 ml/M (USA) 300 ml/M(Europe)
200 ml/M(Japan)
Vein wall hypertrophy enough
Superficial enough
12. How is a successful fistula?
Allon et al, KI 62: 1109-24, 2002
Experience ( >12 procedures) of the surgeon
Site of fistula:
primary failure rate: 66% in forearm; 41% upper arm
Pre-operative sonographic vascular mapping:
age, DM, race, BMI
Hand exercise ?
Anti-platelet agents for 3 ~ 6 W
Kaufman et a, Semin dial 13: 40-46, 2000
13. Pre-operative vascular mapping
Allon et al, KI 62: 1109-24, 2002
Mapping with ultrasonography or venography
Criteria for placement of a shunt:
Minimum vein diameter: 0.25cm (AVF)
Minimum vein diameter: 0.40cm (AVG)
Minimum artery diameter: 0.20cm
Draining vein or central vein: lack of stenosis, sclerosis, or
thrombosis
A change of planned surgical procedure: 31%
Order of preference of vascular access to be
placed: Distal F > Proximal F > Proximal
transposed brachio-basilic F > Upper extremity
G> Thigh G> Unusual G (Necklace, chest wall)
14. Assessment of fistula maturation
Allon et al, KI 62: 1109-24, 2002
Post-operative sonographic measurement at
2M:
A: minimum vein diameter: >0.4cm
B: Access Qb> 500ml/min
A or B: 70%
A+B: 95%
neither: 33%
Time interval for dialysis use: 2 ~ 4M
15. AF fistulas: primary failure
Ivan D. Maya et al: AJKD 2008(University of Alabama at Birmingham)
High primary failure rate: 20 ~ 50%
Steal syndrome: 1 ~ 4%
Post-operative ultrasound to evaluate
maturation: 4 ~ 8 W after surgery
Ultrasound criteria for maturity:
Fistula diameter ≧ 0.4cm
Access flow ≧ 500mL/min
Distance from skin ≦ 0.5cm
16. Primary failure
Primary failure rate : early thrombosis or
failure to mature adequately (Juxta-anastomotic
stenosis/Large accessory veins/Excessively deep fistula )
Primary survival ( intervention-free): time from
access placement to initial intervention
Cumulative survival ( assisted ) : time from
access placement to permanent failure
Primary or cumulative survival at 1 year:
Oliver et al, KI 60: 1532-39, 2001
F > G: if primary failure
excluded F = G: if primary failure
included
17. Effect of clopidogrel on early
failure of AVFs for HD
Multicenter randomized controlled trial: N= 877
Clopidogrel: 300mg loading dose/75mg/D for 6 weeks
Inclusion criteria: upper extremity AVF/start HD within 6 M
Primary outcome: unassisted AVF patency at 6W
Secondary outcome: AVF dialysis suitability ( Use of AVF with 2
needles at Q-b ≧>300 ml/min for 8 sessions this began ≧ 120 days
after AVF creation)
Clopidogrel group: 37% lower risk of thrombosis(RR 0.46
p=0.018); Forearm(RR 0.53); upper arm(RR 0.89)
A surprising high primary failure in both
groups(61%/59%) →more than reducing early fistula
thrombosis in required Dember LM et al: JAMA 299:
2164-71, 2008
18. Anti-platelet agents for fistula
Study N Intervention/Duration Thrombosis (%)
Intervention Control
Andrassy et al 92 Aspirin 500mg/D x 4W 4 23
1974
Grontoft et al 36 Ticlopidine 250mg/D x 4W 11 47
1985
Grontoft et al 260 Ticlopidine 250mg/D x 4W 12 19
1998
Dember et al 877 Clopidegrel 300mg/D(L) 12 19
2008 75mg/D x 6W
DOPPS: N= 2815: aspirin to reduce significantly lower risk of final AVF failure
19. AV fistulas: late failure
Ivan D. Maya et al: AJKD 2008(University of Alabama at Birmingham)
Late fistula failure by stenosis
60% at venous outlet
25% at arterial anastomosis
5% at central vessels
A large aneurysm,
rarely
Thrombosed fistula requires thrombectomy with
48 Hr
Primary patency rate after:
27 ~ 81% at 6M; 18 ~ 70% at 12M
21. AV grafts: graft failure
Ivan D. Maya et al: AJKD 2008(University of Alabama at Birmingham)
Graft failure:
~ 80% thrombosis
~ 20% infection
A large pseudo-aneurysm,
rarely
Underlying stenosis in most thrombosed grafts:
~ 60% Venous
anastomosis 15% venous
outlet 10%
central veins
10% intragraft
5% arterial anastomosis
22. AV grafts: graft failure
Ivan D. Maya et al: AJKD 2008(University of Alabama at Birmingham)
Intervention-free patency after elective
angioplasty: 70 ~ 85% at 3M; 20 ~ 40% at 12M
Intervention-free patency after thrombectomy:
33 ~ 63% at 3M; 10 ~ 39% at 6M
Stents may prolong patency in selected grafts:
elastic lesion
No clear advantage of bovine or cadaveric human
vein grafts over PTFE grafts
Polyurethane grafts (Vectra): can be cannulated
within 24 Hr
23. Vascular access stenosis: VNH
Ivan D. Maya et al: AJKD 2008(University of Alabama at Birmingham)
VNH: venous neo-intimal hyperplasia (SMC +
micro-F + microvessels)
Hemo-dynamic turbulence: an shear forces
Dialysis needle injury
Surgical vascular damage
PTFE
Uremia
Vascular damage from angioplasty
Expression of genes for cytokines
Local anti-proliferative drug delivery system:
Human study in progress
24. Preventive strategy for VNH
Strategy Mechanism of action Used in AVF
model
Mechanical design
Tapered graft and pre-cuffed graft geometry at anastomosis Y
Deculluarized xenograft elastic mismatch between graft/vessel Y
Biological reagents
Antisense ODNs inhibit DNA transcription N
Decoy(E2F) inhibit cell cycle progression Y
Gene transfer
VEGF promote endothelialization N
C-type natriuretic peptide inhibit proliferation via cGMP Y
Cell based therapy
Endothelial progenitor cells promote endothelialization of graft surface Y
Endothelial cell implant promote endothelial function Y
Small molecule drugs
Rapamycin inhibit protein translation Y
Paclitaxel inhibit mitosis by stabilizing microtubules Y
Dypiridamole inhibit phosphodiesterase activity Y
Imatinib inhibit PDGF receptor activity N
Irradiation induce DNA damage Y
ODN: antisense oligonucleotide Li Li Christi et al: KI 74 1247-61, 2008(University of Utah, USA)
28. Definition of CRB
Public Health Agency of Canada
Definite CRB diagnosis:
1> blood cultures from both
catheter lumen and a peripheral vein grow
the same organism
2>Colony count in catheter (C) ≧ 5
~ 10X colony count in vein (V)
or C ≧ V, 2 Hours earlier
False positive diagnosis: colonization if
from only one lumen
29. Diagnosis of CRB
Probable CRB diagnosis: ≧2 positive blood
culture ( blood culture/catheter tip:+/- or -/+
) + no evidence of a source of infection
other than catheter
Possible CRB diagnosis: negative or single
blood culture + no evidence of a source of
infection other than catheter , but fever
↓after catheter removal
Catheter culture( positive ): CRB 63%
30. Catheter-related bacteremia (CRB)
Similar rates but different average time
tunneled: 1/1000 catheter-days
non-tunneled: 1.54/1000 catheter-days
(p=0.98) Cuevas et al, JASN 1999
tunneled: 66.2 days
non-tunneled: 20.6 days
35% of patients within 3 months
48% of patients within 6 months
31. Risk factors for CRB
Femoral route
Duration of catheter use ( FVC: 5D; JVC: 3 ~ 4W)
Nasal/skin colonization with S.A.
Poor personal hygiene:
Povidone-iodine/Mupirocin over exit site of
catheter
Use of occlusive transparent dressing
DM
Immuno-suppression
Low albumin; high ferritin
33. Use rate of HD permanent
catheter < 10%
NKF-K/DOQI guidelines
34. CQI process to reduce catheter rates
in incident patients: a call to action
1. Discuss with referral sources about
criteria for referral: GFR≦ 30 ml/min
2. Refer patients and family to educational classes about treatment options
that should include PD, transplantation, etc: GFR ≦ 20 ml/min
3.Explicitly discuss with patients and family the need for a permanent
access at a GFR ≦ 20 ml/min
4.Track success of surgical outcomes by surgeon
Refer back to surgeon in 6-8 weeks if fistula is not maturing
5.Provide full disclosure of catheter related risks to patients and family
who refuse surgery for permanent access
6.Weaning of a medi-alert bracelet to protect one arm from veni-puncture
7.Classify requests to hospitals for access placement as urgent
RM Hakim et al: K 76: 1040-1048, 2009
35. Prophylaxis of CRB
Nasal mupirocin or 5-D course of oral
RIF/3M: S.A. carrier (50% in HD )who
have a previous catheter-related bacteremia
caused by S.A. and continue to need HD
catheter ongoing
by IDSA: Infectious Diseases Society of America
Prophylaxis of exit site colonization by mupirocin
or polysporin( Bacitracin+gramicidin+polymyxin
B) ointment at exit site
Lock therapy: GM/Citrate; Taurolidine/Citrate
36. Vancomycin plus Gentamicin in febrile HD
Life-threatening infection by β-lactam resistant
GPC or MRSA
GPC infection+ serious allergy to β-lactam
antibiotics
Antibiotic-associated colitis unresponsive to
Metronidazole or that is life-threatening
Prophylaxis of endocarditis in high-risk Patients:
Presence of central venous dialysis catheter
Alternative:Vancomycin plus 3rd cephalosporin
Rationale: mixed bacteremia 9.8 ~ 12.2%
37. Clinical approach to (tunneled) CRB
Ivan D. Maya et al: AJKD 2008(University of Alabama at Birmingham)
Vancomycin/Ceftazidime or GM
/Antibiotic lock
Negative culture Positive culture Positive culture
X 5D Fever resolve in 2-3D Fever persists
Catheter(-)
CNS GNB CPS Candida ECHO
Stop Metastatic
Catheter(+) Workup: bone
Keep lock Catheter(-) Catheter(-) Anti Duration
Anti: 3W Anti: 3W Fluconazole 6-8W
Guidewire Consider 2W
exchange ECHO/bone scan
38. Catheter removal ?
Non-cuffed Cuffed
Exit site infection Yes No
Tunnel infection Yes Yes
Catheter-related Yes S.A.: Yes
bacteremia(CRB) CNS: No ?
Enterococcus: Yes
39. Antibiotic dosing in HD patients
Systemic antibiotics
Vancomycin 20mg/Kg loading during last one hour ; 500 mg TIW
Gentamicin 1mg/Kg (maximum <100mg) TIW
Ceftazidime 1G TIW
Cefazolin 20mg/Kg TIW
Daptomycin 6mg/Kg TIW
Antibiotic lock: volume of solution(ml)
Vancomycin/Ceftazidime /Heparin: 1.0 /0.5/0.5
Vancomycin/Heparin: 1.0/1.0
Ceftazidime/Heparin: 1.0/1.0
Cefazolin/Heparin: 1.0/1.0
40. Tunnel infection
CDC guideline:
Erythema, tenderness, and induration in
tissues overlying the catheter + > 2cm from the exit site
Public Health Agency of Canada:
Definite:
1> Purulent discharge from tunnel
2> Erythema, tenderness, induration(2/3) at
tunnel with a positive culture from serous discharge
Probable: Erythema, tenderness,
induration(2/3) at tunnel with serous discharge, but
negative culture /no discharge, but lack of alternative
Possible:
Erythema, tenderness, induration(2/3) at tunnel , but
42. Exit site infection
CDC guideline:
Erythema, tenderness, and induration or purulence in
tissues overlying the catheter within 2cm from the exit
site
Public Health Agency of Canada:
Definite:
1> Purulent discharge at exit site
2> Erythema, tenderness, induration(2/3) at exit site
with a positive culture from serous discharge
Probable: Erythema, tenderness, induration(2/3) at
exit site with serous discharge, but negative culture /no
discharge, but lack of alternative
Possible: Erythema, tenderness,
induration(2/3) at exit site , but alternative cause cannot be
ruled out
44. AVG infection
30-day infection rate: 6%
Risk factors:
femoral route
poor hygiene
repetitive cannulations
perigraft hematoma formation
prolonged postdialysis bleeding from graft
repeat surgical revisions
HIV status(30%), DM, low albumin, high ferritin
transient bacteremia from distal site or CRB
45. AVG infection: S/S
Local pain, irritation, tenderness
Redness, warmth
Diffuse or local swelling
Skin breakdown
Serous or purulent discharge
Leukocytosis, fever
46. Sub-clavian vein obstruction
CVC placed for > 2 ~ 3 weeks:
40 ~ 50%
If infected:
75%
PTA+/- stent
Veno-venous bypass surgery
Access ligantion
47.
48. Antibiotic-heparin lock therapy
If Vancomycin: 2.0 mg/ml; Ceftazidime:
2.0 mg/ml plus heparin 5000IU/ml, each
concentration > 100µg/ml will persist > 21
days.
Cefazolin, Vancomycin: 10mg/ml;
Ceftazidime, Ciprofloxacin: 10mg/ml;
Gentamycin: 5mg/ml
No benefit to UK instillation as an adjunct
to antibiotic lock
49. Antibiotic lock: indications
Catheterretained during an episode of
catheter-related bacteremia
O’Grady et al, MMWR Morb Mortal Wkly Rep 51: 1-29,
2002
Historyof multiple catheter-related
bacterremias despite optimal aseptic
technique
Mernet et al, Clinical Infect Dis 32: 1249-72, 2001
51. Ideal lock solution for prophylaxis
Prophylaxis of bio-film formation → CRB↓
1> Cidal activity against a broad spectrum
of GPC/GNB/Fungi
2> Low likelihood of promoting
antibiotic resistant bacteria
3> Compatible with
catheter material and anticoagulant agent
4> Safe if inadvertently instilled
52. Potential antimicrobial lock solutions
Michael Allon: AJKD 44: 2004
1st 2nd 3rd 4th
殺菌 低阻 質合
安全
GM 40mg/dl /Citrate OK No OK OK
30% Citrate OK OK OK OK
70% Isopropyl alcohol OK OK OK No
Taurolidine OK OK OK No
53. CRB prevalence: per 1000 days
4.5
4
3.5
3
2.5 Heparin lock
2 Antimicrobial lock
1.5
1
0.5
0
Dogra Mcintyre Kim Nori Saxena
55. Antibiotic lock: barriers
All randomized trials: F-U for < 6M
Selection of antibiotic resistant infection if
longer use
Systemic toxicity from leaks into
circulation 10-fold lower concentration of
GM: 4 ~ 5 mg/mL
Economic
FDA not approved