the dialysis patient in the ED

introduction

the dialysis patient presents unique complexities to ED staff and early discussion with a renal team is advisable.
many peripheral hospitals have satellite outpatient dialysis services managed by a parent renal unit in a tertiary hospital, although dialysis is limited to routine dialysis and not to manage severe acute hyperkalaemia.
as a general rule, patients from these services who develop significant medical issues and present to the ED, should have their care discussed with their parent renal unit, in the first instance rather than a local renal unit.
if dialysis patients require admission to hospital, at most hospitals including WH, the patient should be admitted under the renal unit irrespective of their presenting complaint

these patients are at significant risk of both:
- life threatening hyperkalaemia
- fluid overload and acute pulmonary oedema (APO)
this risk increases with length of delay and if the delay has been more than 24hrs, the renal registrar should be contacted ASAP and the patient should have an urgent ECG and U&E on arrival, and if ECG changes or hyperkalaemia, moved to a monitored cubicle urgently and iv access gained (but not via the fistula)
if mod-severe ECG changes of hyperkalaemia, the patient should have Rx started ASAP whilst awaiting emergent dialysis
- start iv 50% glucose 50ml with 10-20 units actrapid insulin over 1hr
- consider iv 1g calcium gluconate 10% 10ml over 3-5min if severe ECG changes

immediate dialysis in a cardiac monitored area (ICU or ED) is preferable to driving K into cells as this then reduces the effectiveness of dialysis in removing K+ resulting in rebound hyperkalaemia after dialysis
- if K > 7mM or wide QRS or loss of P waves, it is probably worth starting insulin/dextrose whilst awaiting dialysis, particularly if there is delay

contact the renal team for advice which is likely to consist of:
- blood cultures and empirical IV antibiotics to Rx any infection
- admission under renal tam
- ultrasound scan to exclude aneurysm or collection

dialysis removes body fluid reducing effective circulating fluid volume and risks hypotension if rate of removal exceeds the person's ability to compensate
most patients have a 10ml/kg/hour maximum hourly ultrafiltration rate during haemodialysis although renal doctor may vary this
daily doses of antihypertensive medication should be given after, and not before, dialysis treatment unless otherwise instructed
hypotensive prone patients should not be given food during dialysis

in seated patients, may present as:
- stroke
- convulsions
- loss of consciousness
in recumbent patients, may present as:
- chest tightness, cough, SOB
- weakness
- arrhythmias
- cardiac arrest

turn blood pump off, do not return blood
clamp lines
position patient on left side, head down (Trendelenberg position) to trap air in the right ventricle of the heart
100% oxygen
resuscitation as needed
determine site of air entry
take dialysis machine out of service for maintenance

acute haemolysis during dialysis may be a medical emergency due to sudden severe hyperkalaemia and anaemia
note that delayed haemolysis of injured red blood cells may continue for some time after the dialysis session has been terminated
may present as:
- back pain/ chest pain/ dyspnoea
- tightness in chest and/or pain in fistula arm
- blood leaving the dialyser is translucent and doesn’t clot (cherry red or port wine colour)
- dramatic deepening of skin pigmentation
- marked fall in haemoglobin
- weakness
- cardiac arrest

stop blood pump and clamp venous and arterial lines
do not return blood to the patient - haemolysed blood has a very potassium content
disconnect patient from dialysis machine
resuscitation as needed
cardiac monitor and ECG, be prepared to Rx hyperkalaemia
take urgent bloods for U&E, FBE, haptoglobin, LDH, bilirubin and AST
collect dialysate sample for assessment of contaminants
dialysis machine must be taken out of service
batch numbers of the fistula needles, blood lines and dialyser must be recorded and communicated to the dialysis consumables provider
water contaminants will affect all patients, thus every patient undergoing dialysis at the same time in the unit should be reviewed for signs of haemolysis including the collection of an urgent FBE specimen