Adult-Gerontology Clinical Nurse Specialist (CNS) Practice Exam

Which statement about renal blood flow (RBF) is least accurate?

1. RBF is higher in females than in males

2. RBF is increased with increasing age, until maturity

3. RBF is decreased in the elderly

4. RBF is increased in the supine position

The correct answer is: RBF is higher in females than in males

The concept of renal blood flow (RBF) is fundamentally linked to kidney function and varies based on several physiological factors. The assertion that RBF is higher in females than in males is considered the least accurate because research generally indicates that RBF is not significantly different between genders when considering body size and surface area. Men typically have larger body mass and kidney size, which can contribute to higher overall RBF relative to body size. RBF typically increases during growth and maturation due to hormonal changes and growth factors. However, in the elderly, RBF is known to decline due to age-related renal changes, such as decreased renal perfusion and nephron loss. Additionally, body position can influence RBF; it is often noted that RBF can increase in certain positions, such as the supine position, as this can enhance venous return and affect renal perfusion dynamics. Therefore, the statement about RBF being higher in females does not align with the broader evidence and understanding of renal physiology, making it the least accurate among the provided choices.