hypokalemia Flashcards
Q: What is hypokalemia?
A: Hypokalemia is defined as a low serum potassium level, usually below 3.5 milliequivalents per liter.
Q: What are the symptoms of mild and severe hypokalemia?
A: Mild hypokalemia can be asymptomatic, but severe hypokalemia can cause life-threatening symptoms like paralysis and cardiac arrhythmias.
Q: What are some common causes of hypokalemia?
A: Hypomagnesemia, low potassium intake, transcellular shift of potassium, extrarenal potassium wasting, increased mineralocorticoid activity, and acid-base disorders.
Q: What initial assessment should be performed if hypokalemia is suspected?
A: Perform an ABCDE assessment to determine if the patient is unstable or stable.
Q: How should you stabilize an unstable hypokalemic patient?
A: Stabilize airway, breathing, and circulation, obtain IV access, put the patient on cardiac telemetry, monitor vital signs, and provide supplemental oxygen if needed.
Q: What steps should be taken for a stable hypokalemic patient?
A: Obtain a focused history and physical examination, labs (comprehensive metabolic panel), and a 12-lead ECG.
Q: What history and physical exam findings are typical in hypokalemia?
A: History: weakness, muscle cramps, ascending paralysis, diuretic or laxative use, severe diarrhea. Physical exam: irregular pulse, decreased deep tendon reflexes.
Q: What lab and ECG findings are typical in hypokalemia?
A: Serum potassium below 3.5 milliequivalents per liter, ECG: broad flat T waves, ST segment depression, U waves, prolonged PR or QT interval.
Q: What is pseudohypokalemia and what causes it?
A: Pseudohypokalemia is a falsely low potassium level caused by blood sample being left in a warm environment or excessive potassium uptake by cancerous cells in leukemia.
Q: What immediate treatment is needed for severe hypokalemia with ECG changes or cardiac arrhythmia?
A: Administer an IV infusion of potassium and IV magnesium if Torsades de Pointes is present.
Q: What should be checked after confirming hypokalemia?
A: Check serum magnesium levels.
Q: How does hypomagnesemia affect hypokalemia?
A: Hypomagnesemia exacerbates hypokalemia by accelerating renal potassium wasting and impairing reuptake.
Q: What are the causes of hypokalemia due to low potassium intake?
A: Profound malnutrition, alcohol overuse, or pica.
Q: What conditions are associated with transcellular potassium shift causing hypokalemia?
A: Medication-induced hypokalemia (beta agonists, theophylline, insulin), hyperthyroidism, familial hypokalemic periodic paralysis, thyrotoxic periodic paralysis.
Q: What steps should be taken if there is no transcellular potassium shift?
A: Order labs to check urine potassium and creatinine to calculate the urine potassium-to-creatinine ratio.
