Dialysis is surprisingly difficult to find information about. In the emergency department, I think we're only interested in:
- how do we not look stupid when a renal patient comes
- which patients do we need to arrange urgent dialysis
- what do we do differently with a sick patient on
There are two main types of "routine" dialysis. In ICU it
is different, and their dialysis is normally continuous,
and there are many different types.
Fine fibre tubes mimic the body's glomeruli, and filter
the blood. Semi permiable. Waste products carried away.
You need hydrostatic pressure to be able to increase.
- Peritoneal dialysis
Dialysis fluid introduced into the adbdominal cavity.
Waste transfers through the peritoneal membrane into the
fluid. Abdomen then drained. Could be continuous
ambulatory peritoneal dialysis - which doesn't need a
machine, or continuous cycler-assisted peritoneal
I think the most common cause of urgent dialysis from the
ED is hyperkalaemia, and potentially drug overdose.
Dialysis might also be indicated for pulmonary oedema.
Not all drugs are dialysed out successfully.
Sick Dialysis Patient
- Speak to their renal unit
- Check electrolytes
- Fluid overload normally needs dialysis, as diuretics
need functioning kidneys
- Infection is a leading cause of death - always send
cultures. Pyrexia is often related to gram positive
- Anticoagulation - renal failure often leads to a
bleeding tendency. Ask which anticoagulants have been
- Dialysis related hypotension is the most frequent
symptomatic complication. It is caused by reflex
withdrawal of sympathetic tone resulting from reduced
left ventricular filling. This normally happens because
the patient's fluid balance is suboptimal.
- Cramps are common and might be due to volume depletion
and tissue hypoxia. Hypertonic fluid, like 50mls of 50%
dextrose often raises plasma osmolality and helps.
- The most serious acute events during dialysis include
air embolism, line disconnection leading to haemorrhage,
acute haemolysis or toxicity related to line kinking or
dialysis contamination, and acute allergic reactions to
dialysers or sterilants (ethylene oxide).
Don't touch the fistula. When cannulating use veins as
distal as possible, to try and preserve the bigger access.
Bleeding fistula are often caused by infection. They need
compression, possibly topical tranexamic acid, and urgent