CLIFF NOTES – AVF/AVG

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AVF
  • Maturation: 2-3 months
  • ~50% never viable/never mature
  • Relative to AVG:
    • Less inections
    • Longer lifespan
  • Types
    • Radiocephalic (RC)
      • Juxta-anastomatic stenosis
    • Brachiocephalic
      • High rate dialysis associated steal syndrome
      • Cephalic arch stenosis common
    • Brachiobasicilc
      • When cephalic vein is unsuitable
      • Stenosis at proximal swing segment
  • Adequate fistula: Rule of 6’s
    • Flow: > 600 cc/min
    • Diameter: > 0.6 cm
    • Depth: No more than 0.6 cm deep
    • Mature by 6 weeks
  • Most common cause of non maturation = inflow stenosis
    • Other: competing outflow veins
  • Fistula fails to mature at 6 weeks = further eval required
AVG
  • Types:
    • Loop or straight configuration
    • Necklace (axillary to axillary)
  • Graft vein anastomotic stenosis
    • SG > PTA
Cephalic arch
  • Deltopectoral groove to axillary vein
  • Low primary potency rate at 1 year w/ angioplasty alone (~20%)
HeRO graft (hemodialysis reliable outflow)
Dialysis Parameters:
  • Qa = Access flow rate
  • Qb = Dialysis pump flow rate
    • 350-400 cc/min
  • Kt/V = # quantifying dialysis tx adequacy
    • Intervention: <1.2 or decrease >0.2
Indication ~ Dx
  • Prolonged bleeding = outflow stenosis
  • Difficult cannulation = inflow stenosis
Surveillance Imaging
  • AVG < 600cc/min or <1000 cc/min if > 25% drop (referral for IR intervention)
  • AVF < 400 cc/min or <1000 cc/min if > 25% drop (referral for IR intervention)
  • Anastomotic stenosis PSV
    • >400 cm/sec
Physical Exam:
  1. Palpation:
    1. Inflow stenosis: weak pulse
    2. Outflow stenosis: increased pulse
  2. K < 6.5 if no EKG changes => IR interventions
National Kidney Foundation-Kidney Disease Outcomes Quality Initiative (NKF-KDOQI) – Guidelines (LINK)