can someone help me with hypokalemia?

[totoy1]

Ø The present condition stated 5 days PTA when the patient experienced LBM watery in character, non-blood tinged, non mucoid, foul smelling with associated abdominal pain, cramps in character. No associated vomiting. Patient self medicated with Diatabs affording temporary relief of LBM.

Ø 1 day PTA, patient no longer had LBM but this time patient experienced submission. weakness of lower extremities promptly consult and subsequent

->it's the cause of her admission, can someone help me to make a patophysiology for hypokalemia. thanks in advanced. we will going to have a case presentation today. i badly need it.

[rachelgeorgina]

Have you heard of Google?

Hypokalemia: low concentration of potassium in the blood. (Go look up why potassium is important if you don't know that one, otherwise none of this will make sense.)

Pathophysiology

Potassium is essential for many body functions, including muscle and nerve activity. The electrochemical gradient of potassium between the intracellular and extracellular space is essential for nerve function; in particular, potassium is needed to repolarize the cell membrane to a resting state after an action potential has passed. Decreased potassium levels in the extracellular space will cause hyperpolarization of the resting membrane potential. This hyperpolarization is caused by the effect of the altered potassium gradient on resting membrane potential as defined by the Goldman equation. As a result, a greater than normal stimulus is required for depolarization of the membrane in order to initiate an action potential.

In certain conditions, this will make cells less excitable. However, in the heart, it causes myocytes to become hyperexcitable. Lower membrane potentials in the atrium may cause arrhythmias because of more complete recovery from sodium-channel inactivation, making the triggering of an action potential more likely. In addition, the reduced extracellular potassium (paradoxically) inhibits the activity of the IKr potassium current[9] and delays ventricular repolarization. This delayed repolarization may promote reentrant arrythmias.

- The Wik.

In short, one's potassium needs to be within normal ranges or else you see:

Mild hypokalemia is often without symptoms, although it may cause a small elevation of blood pressure,[2] and can occasionally provoke cardiac arrhythmias.

Moderate hypokalemia, with serum potassium concentrations of 2.5-3 mEq/L, may cause muscular weakness, myalgia, and muscle cramps (owing to disturbed function of the skeletal muscles), and constipation (from disturbed function of smooth muscles).

With more severe hypokalemia, flaccid paralysis, hyporeflexia, and tetany may result. There are reports of rhabdomyolysis occurring with profound hypokalemia with serum potassium levels less than 2 mEq/L. Respiratory depression from severe impairment of skeletal muscle function is found in many patients.

Some electrocardiographic (ECG) findings associated with hypokalemia are flattened T waves and prolongation of the QT interval. The prolonged QT interval may lead to arrhythmias.

- The Wik

Pt you describe sounds like hypokalemia is a result of prolonged:

Gastrointestinal/integument loss

A more common cause is excessive loss of potassium, often associated with heavy fluid losses that "flush" potassium out of the body. Typically, this is a consequence of vomiting, diarrhea, excessive perspiration, or losses associated with surgical procedures

- The Wik

[Daytonite, BSN, RN]

see potassium.doc for signs and symptoms.