Question

A 59 year old man was reffered to the hospital for hypertension, impaired immune system and chronic bacterial infection. Laboratory analysis revaled his potassium serum concentration to be 8.50 mEq/L and his ECG showed arrhythmias with widened QRS interval.

A) Exaplain in detail the biological mechanism on how his blood potassium concentration could have affected his nervous and cardiac resting membrane potential.

B) Explain in detail how this patient's severe hyperkalemia contributes to his chronic skin infections.

Answer 1

Ans 1- In hyperkalemia, the resting membrane potential is decreased , and the membrane becomes partially depolarized . Initially , this increases membrane excitability . However, on prolonged depolarization , the cell membrane will become more refractory and less likely to Fully depolarize .

First ,in case of hyperkalemia, the resting membrane potentialis shifted to a less negative value , that is , from -90mV to -80mV , which in turn moves resting membrane potential closer to the normal threshold potential of -75mV , resulting in increased myocyte excitability.

Ans 2- Normally adrenal glands releases hormone which Strengthens immunity and body against infections , in above case hyperkalemia affects adrenal gland function and hence release of hormones is affected and hence skin infections occur.