The Cardiovascular
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Kt/V for haemodialysis adequacy (Daugirdas)

Single-pool Kt/V from pre/post urea, time and fluid removal.

Kt/V for haemodialysis adequacy (Daugirdas)
Pre-dialysis BUN (urea nitrogen)
mg/dL
Post-dialysis BUN (urea nitrogen)
mg/dL
Dialysis session length
hours
Ultrafiltration volume removed
L
Post-dialysis weight
kg
Complete the fields above to see the result.

When to use

  • Assessing delivered dose of thrice-weekly intermittent haemodialysis.

Formula

Kt/V = -ln(R - 0.008 x t) + (4 - 3.5 x R) x UF/W, where R = post/pre BUN, t = hours, UF = litres removed, W = post-dialysis weight (kg).

Pearls and pitfalls

  • Guidelines target single-pool Kt/V >=1.2 per session for three-times-weekly schedules.
  • Accurate post-dialysis BUN sampling (slow flow/stop-pump technique) avoids overestimating clearance.

References

  1. Daugirdas JT. J Am Soc Nephrol. 1993;4(5):1205-13.