Table 2

Achieving convection volume ≥23 L/treatment session

Processed BV (L)‡FF
20
2122232425262728293031*
Treatment time 3.5 hours
 Qb† 300 mL/min63.012.613.213.914.515.115.816.417.017.618.318.919.5
 Qb 350 mL/min73.514.715.416.216.917.618.419.119.820.621.322.122.8
 Qb 400 mL/min84.016.817.618.519.320.221.021.822.723.524.425.226.0
Treatment time 4.0 hours
 Qb 300 mL/min72.014.415.115.816.617.318.018.719.420.220.921.622.3
 Qb 350 mL/min84.016.817.618.519.320.221.021.822.723.524.425.226.0
 Qb 400 mL/min96.019.220.221.122.123.024.025.025.926.927.828.829.8
Treatment time .4.5 hours
 Qb 300 mL/min81.016.217.017.818.619.420.321.121.922.723.524.325.1
 Qb 350 mL/min94.518.919.820.821.722.723.624.625.526.527.428.429.3
 Qb 400 mL/min108.021.622.723.824.825.927.028.129.230.231.232.433.5
  • This table shows the interaction between session treatment time, blood flow rate through the extra corporeal circuit and ‘filtration fraction’. Convection volumes of ≥23 L/session are best achieved by a 4-hour session with a minimum blood flow of 350 mL/min. Convection volumes ≥23 L/treatment are marked in green.

  • Formula: Convection volumes in post-dilution HDF in relation to treatment time.

  • *Filtration fraction (as a percentage of blood flow: (convective flow rate / blood flow rate)×100).

  • †Effective blood flow rate (Qb).

  • ‡ BV = blood volume

  • BV, blood value; FF, filtration fraction.