Thread by @edgarvlermamd

Hemodialysis 101: AVF/ AVG
#Nephpearls #DialysisDirector

Sites for AVF creation in the upper extremity #Nephpearls #NephJC

Various configurations and sites for AVG placement #Nephpearls #DialysisDirector

Neointimal hyperplasia
📌 Higher risk in AVG
📌 Usually in the venous segment downstream from the graft-vein anastomosis

👉🏼 Poor flow in the graft
👉🏼 Prolonged bleeding after removal of needles (⬆️ Intragraft pressure)
👉🏼 Leads to graft thrombosis
#Nephpearls #DialysisDirector

AVF creation: For successful surgical anastomosis -
📌 Minimum vein lumen diameter should be about 2.5 mm
📌 Minimal arterial diameter should be 2.0 mm
#Nephpearls #DialysisDirector
👉🏼 journals.sagepub.com/doi/pdf/10.530…

Steal due to fistula on the same side as an internal mammary artery-CABG
#Nephpearls #DialysisDirector
👉🏼 ncbi.nlm.nih.gov/m/pubmed/23344…

AVF maturation: Rule of 6
📌 Assess for signs of maturation at 4-6 weeks
📌 Vein diameter at least 6 mm (at time of intended use)
📌 < 6 mm below the skin
📌 BFR of at least 600 mL/min
📌 Straight segment for cannulation at least 6 cm in length
#Nephpearls #DialysisDirector

AVG maturation: A PTFE graft should not be cannulated for at least 2 weeks after placement
It is considered mature when -
📌 Edema and erythema have resolved
📌 AVG course is easily palpable
#Nephpearls #DialysisDirector

Most common sites of AVF/ AVG stenosis:
📌 AVF: juxta-anastomotic region
📌 AVG: at or just distal to the graft–vein anastomosis
#Nephpearls #DialysisDirector

Physical Examination findings with various forms of access dysfunction #Nephpearls #DialysisDirector

Access surveillance
📌 Trending ionic dialysance
📌 Trending venous outflow pressures
📌 Periodic measurement of access BFR
👉🏼 Direct measurement of access flow by saline dilution
👉🏼 Blood Temperature Module
👉🏼 Online Hemoglobin Monitor
📌 Doppler US
#Nephpearls #DialysisDirector

Dialysis access asso. hand ischemia aka “steal syndrome”
📌 Complicates 1-20% of accesses
📌 ‘’Arterial steal’ from retrograde flow in the distal artery toward the access
👉🏼 Arterial stenosis/ distal arteriopathy involving small vessels, contributory
#Nephpearls #DialysisDirector

Dialysis access-associated steal syndrome: Treatment from @RenalFellowNtwk @Buck1486
#Nephpearls #DialysisDirector
👉🏼 renalfellow.org/2019/06/30/an-…

Pseudoaneurysm
📌 Trauma to AV access from repeated cannulation in the same area can damage the layers of native vein/ graft material

📌 Signs of impending rupture
👉🏼 Thin/ shiny overlying skin
👉🏼 Prolonged leaking/ ulceration
👉🏼 ⬆️ size of aneurysm
#Nephpearls #DialysisDirector