Hemodynamics — Flashcards

Flashcard 241: How does increased efferent sympathetic firing (e.g. baroreceptor reflex) affect venoconstriction?_____

Answer: Increased venoconstriction

Flashcard 242: A(n) _____ in velocity of blood causes an increase in Reynolds' number

Answer: increase

Flashcard 243: _____ number predicts whether blood flow will be laminar or turbulent

Answer: Reynolds'

Flashcard 244: Norepinephrine causes _____ systolic pressure

Answer: increased

Flashcard 245: What equation may be used to calculate the velocity of blood flow (v) given the flow rate (Q)?_____

Answer: v = Q/A

Flashcard 246: The likelihood of turbulent flow may be calculated using Reynolds' number (Nʀ), which states Nʀ = _____

Answer: (ρ × v × d) / η (Density × Velocity × Diameter / Viscosity)

Extra: Reynolds' number (Nʀ) predicts whether blood flow will be laminar or turbulent. Formula: Nʀ = (ρvd) / η • ρ = density of blood • v = velocity of blood flow • d = diameter of the blood vessel • η = viscosity of blood Interpretation: • < 2000: Laminar flow • > 2000: Likely turbulent flow • > 3000: Always turbulent flow

Flashcard 247: What effect does increased aortic pressure (afterload) have on cardiac wall stress?_____

Answer: Increased wall stress

Flashcard 248: What type of resistance is illustrated by the arrangement of blood vessels in systemic circulation? _____

Answer: Parallel resistance

Flashcard 249: How does EDV change in heart failure with systolic dysfunction? _____

Answer: Increased EDV

Flashcard 250: What is the approximate normal pressure in the pulmonary artery (systolic and diastolic)? _____

Answer: 25/10 mmHg