Evidence-based On-call

Hyperkalaemia

Prevalence
Causes
Clinical features
Investigations
Therapy
Prognosis

Investigations

Repeat the sample if haemolysis is possible ^c
12-lead ECG ^b

Beware of attributing extreme values to haemolysis alone: obtain an ECG while awaiting any repeat potassium readings. ^d
Look for ^b

peaked T waves, small P waves

or worse yet: absent P waves, wide QRS, blurring of ST into T

or worse yet, sine wave pattern

Consider continuous ECG monitoring ^d

If no obvious cause can be found, consider the following investigations ^d

blood count
glucose
arterial blood gas
cortisol level
monitor urine output

Expiry date: September 2005
Levels of Evidence used in grading these guides

Authors	W Lee , CM Ball
Reviewer	C Clase
CAT Writers	W Lee , CM Ball