72-year-old starting dialysis on a catheter — attempt, configuration, surveillance and cannulation counselling

Examiner notes

Probe five domains: (1) elderly attempt pricing with 70-plus benefit, 90-plus uncertainty, dependence months and 75-plus forearm verdict^[9][13][15]; (2) distal-to-proximal configuration with sole-RCT staging numbers and VQI reconciliation^[23][29][31]; (3) fistula-only surveillance with Cochrane split, flow-trial numbers and 500 threshold^[38][40][44]; (4) rope-ladder default with buttonhole infection pricing^[45][47]; (5) catheter locks, exchange ladder and contralateral discipline^[52][54][55]. Award marks for exact numbers with named papers; deduct for promising maturation, quoting catheter hazards as causal, surveying grafts, defaulting to buttonhole, or placing ipsilateral access without naming the 2.48 penalty.

Model dialogue

Is a fistula worth attempting at 72? Yes with priced honesty: benefit survives past 70 (HR 0.56) — but predialysis creation reaches dialysis access-less in half, fistulas cost more catheter months for 6 months while earning fewer infections and deaths, dependence crosses over only at 12-36 months with more cumulative catheter-days, and weighted advantages fade past 6 months — so attempt with the months consented, graft where waiting is unaffordable.^{[9][10][11][13][14]}

Which configuration, and staged or not? Distal first: radiocephalic preserves proximal sites despite brachiocephalic flow and patency advantages (492 vs 307 mL/min, 88.7 vs 62.9%) — then staged basilic where the vein is small, because the sole RCT stopped early at 33 vs 100% maturation trading 54 for 97 days, pooling differs only at 2-year primary (RR 2.50), and VQI finds adjusted patency tied with less swelling two-stage.^{[23][29][30][31]}

How will you know it is failing? Flow surveillance because it is a fistula: Qa below 500 or a 25% fall triggers fistulography — preemptive repair halves thrombosis (RR 0.5) and loss (RR 0.5) with randomised proofs at 0.022/0.099 and 0.025/0.086 — repaired above 500 for triple benefit — while grafts gain nothing and thrombosed accesses have no superior declot.^{[38][40][41][44][63]}

How should it be needled? Rope-ladder: no preferential buttonhole evidence with randomised pain gain erased — buttonhole earns aneurysm 0.18 but pays bloodstream infection at 2.6-fold with S. aureus in half — so rope-ladder in-centre, buttonhole only for difficult access.^[45][46][47]

What happens to the catheter? Lock it with a studied regimen (minocycline-EDTA 1.1 vs 4.3; gentamicin-citrate 73% cut), exchange by appearance (87.8/75/86.5% cures with 3 weeks directed antibiotics), and place the permanent access contralateral — because ipsilateral history doubles the cumulative fistula hazard (2.48) and central stenosis follows catheters at 2% yearly.^{[52][53][54][55][49]}