Understanding Circulation and Pulse Points

Sep 28, 2024

Anatomy 1352 - Unit Four: Circulation

Overview

  • This unit covers circulation, focusing on the hepatic portal system and fetal circulation.
  • Emphasis on understanding circulation routes and common places for checking pulse.

Circulation and Pulse

  • Pulse is the expansion and relaxation of arteries due to systolic pressure.
  • Closer to the heart = stronger pulse; further = weaker pulse.
  • Common pulse points:
    • Radial Artery: Lateral wrist, easy to access.
    • Brachial Artery: Elbow, used for blood pressure.
    • Carotid Artery: Neck, deeper and harder to feel.
    • Temporal and Facial Arteries: Head, temporal often easier.
    • Femoral, Popliteal, and Dorsalis Pedis Arteries: Thigh, knee, foot.
  • Use different locations based on patient conditions like IVs or injuries.

Circulatory Routes

  • Pulmonary Circulation: Right side of heart to lungs and back.
    • Purpose: Oxygenate blood, remove CO2.
  • Systemic Circulation: Left heart to body and back.
    • Purpose: Deliver oxygen, remove waste.

Major Arteries and Veins

  • Arteries:
    • Subclavian, brachial, radial, femoral, popliteal, tibial.
    • Aorta regions: Ascending, arch, thoracic, abdominal.
    • Renal, hepatic, phrenic arteries for kidneys, liver, diaphragm.
  • Veins:
    • Subclavian, axillary, cubital, saphenous (important for bypass).
    • Jugular veins for head, superior vena cava for return to heart.
    • Azygos vein drains chest wall.

Hepatic Portal System

  • Blood flow around intestines and liver.
  • Nutrients absorbed into blood from intestines via capillaries.
  • Hepatic Portal Vein: Nutrient-rich blood to liver.
  • Hepatic Artery: Oxygen to liver.
  • Liver processes nutrients, stores or releases into circulation.

Fetal Circulation

  • Fetus gets oxygen from placenta, not lungs.
  • Umbilical Arteries: From iliac arteries to placenta.
  • Umbilical Vein: Returns oxygen-rich blood to fetus.
  • Bypasses: Foramen ovale (right to left atrium), ductus arteriosus (pulmonary trunk to aorta).
  • Adjustments at birth: Lungs expand, pressure changes, ductus arteriosus closes, foramen ovale closes over months.

Common Conditions

  • Syncope: Fainting from stress, drug induction, or orthostatic hypotension.
  • Aneurysm: Weakness in artery wall, risk of rupture.
    • Causes: Atherosclerosis, trauma, congenital defects.

Key Points to Remember

  • Understand circulation routes and purposes.
  • Know major arteries and veins.
  • Grasp fetal circulation and transitions post-birth.
  • Be aware of conditions like syncope and aneurysms.