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Draft: not yet reviewed by a clinician

Use this page to prepare questions for your care team. It does not replace their advice. Your own targets and doses come from your nephrologist, diabetes team and renal dietitian.

Dialysis adequacy

In short

"Adequacy" means dialysis is removing enough waste and fluid for you to stay well. On hemodialysis the main number is Kt/V, worked out from blood taken before and after a session. On peritoneal dialysis there is no single number to hit: the team looks at how you feel, your fluid, your nutrition, your blood tests and the clearance results together (ISPD 2020). The number you control most is time on dialysis: shortening sessions lowers the dose you get, and skipping sessions is linked with a higher risk of death (KDOQI 2015; DOPPS 2003).

Your numbers

Kt/V has no unit, so it is the same in every country.

Hemodialysis (KDOQI 2015):

Schedule Measure Target Minimum delivered
3 sessions a week single-pool Kt/V (spKt/V) per session 1.4 1.2
Other schedules (for example short daily or nocturnal home hemodialysis) standard Kt/V (stdKt/V) per week 2.3 2.1
3 sessions a week with little remaining kidney function session length – at least 3 hours

"Little remaining kidney function" means a urea clearance under about 2 mL/min. If you still pass a good amount of urine, your team may count it, as long as it is measured from time to time (KDOQI 2015).

What Kt/V means. K is how fast the dialyser clears urea, t is the time on dialysis, and V is the water in your body. A Kt/V of 1.4 means the session cleared urea from about 1.4 times your body water. Longer time (t) or better blood flow through your access raises it.

Peritoneal dialysis (ISPD 2020):

  • No specific clearance number guarantees enough dialysis for everyone.
  • Routinely aiming for a weekly Kt/V above 1.7 has shown no survival advantage.
  • If your symptoms, nutrition and fluid are all under control, the prescription does not need to change just to reach a number.
  • Your urine output (remaining kidney function) matters a lot and is protected; avoiding dehydration and low blood pressure helps.

US rules. US dialysis units must aim for a Kt/V of at least 1.2 per hemodialysis session and a weekly Kt/V of at least 1.7 on peritoneal dialysis, or meet another accepted standard of adequacy (42 CFR 494.90).

How often. If you are on hemodialysis, at home or in a center, your blood is tested once a month (NIDDK). On peritoneal dialysis your unit tests clearance and the peritoneal membrane from time to time; ask how often.

What lowers adequacy on hemodialysis

Problem What you can do
Missed sessions. Skipping one or more sessions a month was linked with a 30 % higher risk of death (DOPPS 2003) Never skip. If you must miss one, call the unit to make it up
Shortened sessions (coming off early) Stay for the full time; tell the team if cramps or low blood pressure make it hard, so they can fix the cause
Access problems: narrowing, clotting, or blood going round twice (recirculation). An unexplained drop of more than 0.2 in Kt/V can be a sign (KDOQI 2019 vascular access) Feel for the buzz (thrill) every day; report changes the same day (Dialysis access)
Catheter problems, which can lower blood flow and Kt/V (KDOQI 2019 vascular access) Ask about a fistula or graft if you still use a catheter
Large weight gains between sessions, high blood pressure, or high potassium or phosphate KDOQI suggests a longer or extra session for these (KDOQI 2015); keep to your fluid limit (Fluid)

The day after the long 2-day gap is the riskiest day of the week on a 3-a-week schedule (Foley 2011).

Signs that dialysis may not be enough

Tell your team if you notice these, even if your Kt/V looks fine. They are among the reasons KDIGO lists for starting dialysis, so on dialysis they can mean you need more (KDIGO 2024, Table 41):

  • poor appetite, nausea, or weight and muscle loss that diet advice does not fix;
  • itching that will not go away;
  • trouble thinking clearly, or feeling more tired and weak;
  • fluid or blood pressure you cannot keep under control: swelling, breathlessness;
  • chest pain: it can be a sign of pericarditis, an inflammation around the heart, which is urgent.

When dialysis is working, many people notice more energy and a better appetite (NIDDK).

What to do

  • Do every session for the full time, and every exchange or cycler night as prescribed.
  • Ask for your Kt/V each month and write it on your lab tracker.
  • Check your fistula or graft buzz every day; call the same day if it stops or changes.
  • Keep weight gains between sessions within your team's limit (Fluid; Dialysis days).
  • Tell your team how you feel: appetite, sleep, itch, energy, swelling. These count as much as the number.
  • If you pass urine, tell your team how much, and ask how to protect it (see also Medicines to avoid).

In the app

The app does not store Kt/V. With your dialysis days set, it totals potassium, sodium and fluid since your last session, so you can see the long gap coming (Targets and warnings).

Examples

  • Below target. Lena's spKt/V was 1.15, below the 1.2 minimum. She had been coming off 20 minutes early twice a week because of cramps. Her team treated the cramps, and with full sessions her next Kt/V was 1.45.
  • A quiet access warning. Ade's Kt/V fell from 1.5 to 1.25 with no change in his prescription. His unit checked his fistula and found a narrowing, which was treated.
  • Peritoneal dialysis, feeling well. Rosa's weekly Kt/V is 1.7. She eats well, her fluid and blood tests are fine, and she still passes urine. Her team keeps her prescription the same rather than pushing the number higher (ISPD 2020).

Ask your care team

  1. What was my last Kt/V (or clearance on PD), and is it on target?
  2. Should I have longer or extra sessions?
  3. Is my access working well? When was it last checked?
  4. How much kidney function do I have left, and how do we protect it?
  5. Would home hemodialysis or a different schedule suit me better?

Get help now if…

Call 911 (or your local emergency number)

Severe breathlessness or being unable to lie flat, chest pain, fainting, or a lab potassium of 6.5 mmol/L or more (KDIGO 2024, Table 28). Bleeding from your fistula or graft that is heavy or spurting, or has not stopped after 10–15 minutes of firm pressure: keep pressing while you call (AKF). See Get help now.

Call your dialysis unit today

A missed or shortened session (to make it up), no buzz in your fistula or graft, fever or redness at your access or catheter, or on peritoneal dialysis, cloudy fluid or belly pain (keep the bag).

Sources

Not yet reviewed by a clinician. Facts and sources last checked 2026-10-06.