Nursing care
A client who missed haemodialysis: ranking hyperkalaemia, fluid overload and what can wait
Written and reviewed by Dana Whitfield, RN, MSN · 4 min read · Updated October 2026
Short answer
After a missed haemodialysis session, the two immediate dangers are hyperkalaemia, which can cause fatal arrhythmias, and fluid overload, which can cause pulmonary oedema. The nurse assesses airway, breathing and oxygen saturation, places the client on cardiac monitoring, obtains an urgent potassium level and notifies the provider so dialysis can be arranged. Diet teaching and routine assessment come later.
Why a missed session is dangerous
In kidney failure, dialysis does much of the work of removing potassium and excess fluid. NIDDK explains that fluid builds up between haemodialysis treatments, and MedlinePlus notes that failing kidneys may not remove enough potassium. Missing a scheduled session lengthens the gap, so both accumulate further. The client may look well yet carry a dangerous potassium level.
The MSD Manual describes hyperkalaemia as often silent until it affects the heart. Electrocardiogram changes progress from peaked T waves to widened QRS complexes and loss of P waves, and can end in ventricular fibrillation or asystole. Fluid overload, meanwhile, presents with weight gain, oedema, hypertension, crackles and breathlessness. Both problems need treatment that only dialysis or urgent medical therapy can provide.
First actions: breathing, cardiac monitoring and potassium
Start with airway and breathing. A client who is short of breath, unable to lie flat, has crackles or falling saturation needs upright positioning, oxygen per protocol and urgent provider review because pulmonary oedema can deteriorate quickly. In a client who is breathing comfortably, the next priority is cardiac rhythm: place them on a monitor and obtain a 12-lead ECG per protocol.
Obtain an urgent potassium level and other ordered laboratory tests, and notify the provider and dialysis team. If ECG changes or a high potassium are found, expect emergency treatments described by the MSD Manual, such as intravenous calcium to protect the heart and insulin with glucose to shift potassium into cells, while dialysis is arranged to remove it. Keep resuscitation equipment nearby.
Assessing fluid overload at the bedside
Fluid overload is assessed with weight compared with the client's target or dry weight, blood pressure, jugular venous distension, peripheral and sacral oedema, lung sounds and the ability to lie flat. NIDDK notes that dialysis relieves the shortness of breath and swelling caused by fluid build-up, so these findings worsening after a missed session are expected but still need reporting.
Restrict oral fluids per order while dialysis is arranged and record intake and output accurately. Avoid giving routine intravenous fluids without clear direction, because the client cannot excrete the extra volume. When dialysis does run, monitor for hypotension, cramps and dizziness, which NIDDK links to rapid fluid removal, especially when a large amount has accumulated since the last treatment.
What can wait and what can be delegated
Diet and fluid teaching, exploring why the session was missed, and a full head-to-toe assessment are important but follow stabilisation. Asking about transport problems, symptoms such as feeling unwell after dialysis, cost or depression can prevent future missed sessions, and a social work referral may help. These conversations are more productive once the client is safe.
Assistive personnel can weigh the client, measure intake and output, and obtain routine vital signs once the RN has assessed stability, with clear instructions on what to report. Interpreting the ECG, recognising hyperkalaemia patterns, assessing lung sounds and evaluating response to emergency treatment remain RN responsibilities. Avoid using the fistula arm for blood pressure or blood draws.
Worked example: who and what comes first
Imagine a hypothetical client who skipped two days of dialysis and arrives feeling weak with mild ankle swelling. Breathing is comfortable and saturation is normal. Options: teach about high-potassium foods; weigh the client and compare with dry weight; place the client on a cardiac monitor and request an urgent potassium level; or check the fistula for a thrill and bruit.
Cardiac monitoring with an urgent potassium is the priority because weakness after missed dialysis can signal hyperkalaemia, which may cause a fatal arrhythmia without warning. Weight and fistula checks matter but carry less immediate risk. Teaching waits. If the stem instead described crackles and severe breathlessness, airway and breathing would move to the top.
Sources and further reading
MSD Manual Professional: Hyperkalemia. ECG progression, arrhythmia and arrest risk, IV calcium, insulin with glucose and haemodialysis, with renal failure as a leading cause.
NIDDK: Hemodialysis. Fluid build-up between treatments, fluid limits and shortness of breath and swelling relieved by dialysis.
MedlinePlus: High potassium level. Kidney failure reducing potassium removal, palpitations, weakness, ECG testing and emergency treatment.
The next step on this is the same as on everything else here: answer questions and read the rationales. Our renal and genitourinary practice questions are the closest set to what this page covers.
Common questions
Why is muscle weakness concerning after missed dialysis?
Weakness can be a sign of hyperkalaemia, which also affects heart conduction. It prompts cardiac monitoring and an urgent potassium level rather than reassurance.
Does a normal-looking client mean potassium is safe?
No. Hyperkalaemia can be present with few symptoms until cardiac toxicity appears. Laboratory testing and ECG findings guide the response, not appearance alone.
Which comes first: fluid overload or hyperkalaemia?
It depends on the findings. Respiratory distress from pulmonary oedema is an airway and breathing priority. In a client breathing comfortably, cardiac monitoring and potassium testing for hyperkalaemia come first.