Cardiac Question #30
The nurse is caring for an older client who was admitted for extreme weakness, dizziness, and orthopnea. A diagnosis of heart failure is confirmed. Which of the following tests is a helpful in determining the diagnosis of heart failure?
- Electrolyte Panel
- Liver Function Panel
- 12-lead Electrocardiogram
- Brain Natriuretic Peptide (BNP)
The level of BNP increases with ventricular wall expansion, which occurs as a result of increased pressure. Natriuretic peptides are secreted by the heart as a way to balance and maintain homeostasis with blood pressure, plasma volume, and water/sodium ratios. It is secreted more when ventricles stretch or when chamber wall thickening occurs. BNP increases with straining of heart myocytes and is therefore a helpful tool in determining heart failure with or without systolic dysfunction. While potassium and sodium levels may present with imbalances they are not used to diagnose heart failure. While cardiac changes may be revealed through 12-lead ECG, such changes may not be diagnostic indicators of heart failure. The same holds true for liver function panels.