Potassium distribution

Extracellular vs intracellular

Extracellular [K+]
= 4 mmol/L

Intracellular [K+]
= 140 mmol/L

Body potassium distribution

[KB2:p15]

Total body K+
= 40-45 mmol/kg

• Intracellular fluid = 90%
• Extracellular fluid = 2%
• Bone = 8%

NB:

• K+ in bone is not readily exchangeable
• Exchangeable K+ can be measured using ⁴²K+

Also see Potassium