MEDICINE FOR ALL

Dialysis management in severe cramps:

Immediate:

• Reduce ultrafiltration rate
• Reduce blood flow rate
• Massage limb if possible
• Administer oxygen
• Administer 0.9% sodium chloride (or machine prepared solution) in measured boluses
• Re-assess fluid removal and patient dry weight

Then:

• Re-educate patient re-fluid intake if weight gain is excessive
• Measured native urine output and maximise with diuretics
• Refer to dietitian to review sodium intake

Patients may complain of cramp at varying times during their dialysis session. Mostly cramps is felt in the lower calf muscles but it is not uncommon for cramping pain to be felt in hands, feet, abdomen etc. This can vary from mild to extreme pain and muscle spam.

Causes (these are often multifactorial but commonly):

1. Excessive fluid removal due to large interdialytic fluid gains and incorrect dry weight
2. Poor circulation-unable to adequately perfuse extremities

Sign and symptoms of physiological complication secondary to rate of fluid removal:

• Often the patients recognises no symptoms
• Gradual hypotension during dialysis session
• Yawning
• Muscle tightening and cramps

In patients with chronic hypotension:

• Perform cardiac work up to rule out cardiac causes
• Use haemodiafiltration not standard haemodialysis
• Consider suitability for more frequent dialysis whether at home or in centre
• Consider use of compression stockings and advise re-postural symptoms
• where transplant listed, ensure that transplant team aware that may need perioperative inotropes
• Ensure very close observation of dialysis access; lower blood pressure may accentuate haemodynamic effects of any vessels stenosis
• Consider screening for ischaemic proliferative retinopathy

Prevention:

• Ensure  all patients have  a personalised fluid intake guide that they can understand. Engagement of other family members/ carers may be necessary. This should be reassessed regularly taking into account residual urine output, size, degree of physical activity and any other fluid loss. Dietetic advice should be employed to aid salt and water intake
• Regular assessment of dry wight using clinical parameters and bioimpedance measurements if available
• Regular assessment of use of antihypertensive medication
• Consider use of haemodiafiltration if not already prescribed
• Consider use of blood volume monitoring to guide ultrafiltration
• Consider full cardiac assessment to identify severe left ventricular failure, valvular abnormalities, marked ischaemia or rhythm abnormalities
• Considering further cooling dialysate; it is unlikely that reduction to below 35,5ºC will be helpful
• Consider increasing frequency of dialysis in patients with significant cardiac disease
• Consider home haemodialysis and increased frequency/prolonged hours dialysis for patients who struggle with interdialytic weight gains
• Consider cautious changes in dialysate sodium
• Consider alternative ultafiltration schedules. Sodium profiling should not be used as tends to sodium load patients and worsen interdialytic fluid gains
• Advise against eating and drinking during dialysis
• If hypotension occurs at the beginning of dialysis, consider a fluid bolus at start of dialysis

Immediate action if clinically significant hypotensive episode occur:

• Place the patient in the Tredelenburg position
• Stop ultrafiltration and re-assess fluid loss. Keep off ultrafiltration for at least 10-15 mins
• Administer oxygen
• Administer 150 bolus of sodium chloride 0.9%
• If recovery not within 5 minutes consider need for medical review

Hypotension on dialysis can have several causes. An individual it may be multifactorial:

• When the rate of fluid removal exceeds vascular refilling rate. This is more likely to occur when ultrafiltration exceeds the rate of 10-15 ml/kg/hours and when fluid gain between dialysis sessions is excessive
• When a dry weight is not correct and is too low
• When antihypertensive medication or medication affecting the pulse rate does not allow physiological adaptation to fluid removal
• With significant cardiac disease preventing physiological adaptation to fluid removal. This includes significant left ventricular failure, dialysis-induced ischaemia and rhythm abnormalities
• When a patient has significant extra-kidney fluid losses resulting in reduced intravascular volume either temporarily e.g. diarrhoea and vomitting, blood loss on dialysis or long term e.g.  high output ileostomy
• With serious infection particularly sepsis syndrome
• As a chronic condition in long term, particularly anephric patients

Ultrafiltration can only be performed at a maximum rate of 10-15 ml/kg/hour:

• Assessment of residual urine output. It is essential that this is regularly recorded as it is a vital piece of information for guiding individualised fluid intake guidance. It should be measured within a month of commencing chronic haemodialysis and every six months thereafter. Furosemide should be used to help maintain urine output. In addition, nephrotoxic drugs should be avoided in patients with residual kidney functions
• Insensible loss (e.g. fluid lost through sweating and gastrointestinal loss) is approximately 750 ml/day. This may be greater in hot weather or in patients with higher than average activity levels. Individualised fluid intake guidance should be developed. In an anuric patients this generally amounts to a 1000 ml/day fluid restriction but will obviously depend on the patient’s size. This can be increased in a patient passing urine. In general fluid intake should be such that fluid gained between dialysis sessions is 2 litres or less and always such that weigh gain is <5% between even  a 3 day break. Dietetic advice should be given with regards to low salt intake in addition,
• Calculated fluid removal should be based on patient’s dry weight. However ultrafiltration rates should not be higher than 10-15 ml/kg/hour. This is often misquotes as “1 litre per hour” but of course will depend on the patient dry weight  (a 50kg patient is very different from a 120kg patient) and other co-morbidities affecting tolerance to rate of fluid removal
• Effective estimation of dry weght is important and should be reviewed regularly. This can be difficult and should be based upon blood venous pressure, peripheral oedema, any symptoms of pulmonary oedema and bioimpedance measures if available.
• If fluids removal results in hypotension or symptoms hypovolemia, above dry weight various methods can be utilised to aid adequate fluid removal
• If patient is still not be able to tolerate removal of gained fluid, then consideration should be given increased frequency of dialysis