Hemodynamics — Flashcards

Flashcard 251: Relative polycythemia is characterized by _____ plasma volume

Answer: decreased

Flashcard 252: What effect does increased afterload have on end-systolic volume? _____

Answer: Increased ESV

Flashcard 253: What is the major factor determining blood flow to resting skeletal muscle?

Answer: Sympathetic innervation (α1 receptors)

Extra: At rest, skeletal muscle blood flow is primarily controlled by **sympathetic innervation** (extrinsic control). During exercise, blood flow is dominated by **local metabolic factors** (intrinsic control/autoregulation) such as lactate, adenosine, and K+.

Flashcard 254: What effect does increased preload have on ejection fraction? _____

Answer: Increased EF

Flashcard 255: How does increased efferent sympathetic firing (e.g. baroreceptor reflex) affect TPR?_____

Answer: Increased TPR (via increased arteriolar vasoconstriction)

Flashcard 256: The Kussmaul sign (increased JVP on inspiration) occurs due to failure of negative intrathoracic pressure to be transmitted to the _____ during inspiration

Answer: heart

Flashcard 257: What equation may be used to calculate Mean Arterial Pressure (MAP) given a patient's blood pressure?

Answer: MAP = 2/3 diastolic pressure + 1/3 systolic pressure

Flashcard 258: How do SVR and afterload change during distributive shock?_____

Answer: Severely decreased

Flashcard 259: In addition to it's actions on serum osmolarity, ADH (vasopressin) may also cause _____

Answer: contraction of vascular smooth muscle (regulate blood pressure)

Flashcard 260: When a blood vessel is added to a system in parallel, the total resistance _____

Answer: decreases