75% off all plans

Hemodynamic Disorders

On this page

Edema & Fluid Balance - Water Woes

  • Edema: Excess interstitial fluid. Body water: ~60% total weight (ICF 2/3, ECF 1/3).
  • Starling's Equation: Net Filtration = $K_f \times [(P_c - P_i) - \sigma (\pi_c - \pi_i)]$
  • Key Pathophysiology:
    • ↑ Capillary hydrostatic pressure ($P_c$): Heart failure, venous obstruction.
    • ↓ Plasma oncotic pressure ($%pi_c$): Nephrotic syndrome, liver failure, malnutrition (↓ albumin).
    • ↑ Capillary permeability: Inflammation, burns.
    • Lymphatic obstruction: Lymphedema, filariasis.
    • Sodium & water retention: Renal dysfunction.
  • Types:
    • Pitting (transudate) vs. Non-pitting (exudate/lymphedema).
    • Localized vs. Generalized (Anasarca). Starling Equation and Capillary Fluid Exchange

⭐ Pitting edema is characteristic of edema fluid rich in protein-poor interstitial fluid, typically seen in cardiac or renal failure.

Hyperemia & Congestion - Red Alert States

  • Hyperemia: Active process. Arteriolar dilation → ↑ inflow. Tissue red (erythema) with oxygenated blood. E.g., inflammation, exercise.
  • Congestion: Passive process. Impaired venous outflow → ↑ volume. Tissue blue-red (cyanotic) from deoxygenated Hb.
    • Systemic: Cardiac failure.
    • Localized: Venous obstruction.
  • Chronic Passive Congestion: Chronic hypoxia → cell death, scarring, hemosiderin macrophages.
    • Lungs: "Heart failure cells" (hemosiderin-laden alveolar macrophages).
    • Liver: "Nutmeg liver" (centrilobular congestion & necrosis). Nutmeg liver gross appearance

⭐ Nutmeg liver is the classic gross appearance of chronic passive hepatic congestion, often due to right-sided heart failure.

Thrombosis & Embolism - Clot Chronicles & Traveling Troubles

  • Thrombosis: Pathological intravascular clot (thrombus) formation.
    • 📌 Virchow's Triad: Stasis, Hypercoagulability, Endothelial injury.
    • Types: Arterial (platelet-rich, pale; e.g., coronary, cerebral arteries); Venous (fibrin-rich, red; e.g., DVT).
  • Virchow's Triad and risk factors
  • Fate of Thrombus:

⭐ Lines of Zahn (grossly and microscopically visible laminations of pale platelets/fibrin alternating with darker RBC-rich layers) are a hallmark of antemortem thrombi, distinguishing them from postmortem clots.

  • Embolism: Detached intravascular solid, liquid, or gaseous mass (embolus) carried by blood to a site distant from its origin.
    • Pulmonary Embolism (PE): >95% originate from deep leg vein DVT; can cause sudden death, right ventricular failure.
    • Systemic Embolism: 80% arise from intracardiac mural thrombi; lodge in lower extremities (75%), brain (10%), viscera.
    • Other types: Fat (long bone fractures), Air (decompression sickness, iatrogenic), Amniotic fluid (labor complication).

Infarction & Shock - Tissue Death & Systemic Shutdown

  • Infarction: Ischemic necrosis from occluded blood supply.

    • Coagulative necrosis (most tissues); liquefactive (brain).
    • Types:
      • Red (hemorrhagic): Venous occlusion, loose tissues (lung, gut), dual circulation, reperfusion injury.
      • White (anemic): Arterial occlusion in solid organs (heart, kidney, spleen).
    • Influenced by: Vascular anatomy, occlusion rate, tissue hypoxia sensitivity. White infarct in spleen
  • Shock: Systemic hypoperfusion leading to cellular hypoxia & vital organ dysfunction.

    • Types:
      • Cardiogenic: Myocardial pump failure (e.g., MI, arrhythmia).
      • Hypovolemic: Reduced circulating blood volume (e.g., hemorrhage, severe dehydration).
      • Distributive: Widespread vasodilation.
        • Septic: Systemic microbial infection.

          ⭐ Septic shock is most commonly caused by gram-positive bacteria, followed by gram-negative bacteria and fungi, and is characterized by systemic vasodilation and endothelial injury.

        • Neurogenic: Loss of vascular tone (e.g., spinal cord injury).
        • Anaphylactic: Systemic hypersensitivity reaction.
      • Obstructive: Mechanical obstruction to cardiac filling or outflow (e.g., pulmonary embolism, cardiac tamponade).
    • Stages of Shock:

High‑Yield Points - ⚡ Biggest Takeaways

  • Virchow's triad (endothelial injury, abnormal blood flow, hypercoagulability) is crucial for thrombosis.
  • Pulmonary embolism (PE) most often originates from deep vein thrombosis (DVT).
  • Lines of Zahn distinguish ante-mortem thrombi.
  • Septic shock is driven by LPS, causing vasodilation and organ dysfunction.
  • Red infarcts in dual-supply organs (lung); white infarcts in end-arterial organs (heart, kidney).
  • Edema mechanisms: ↑ hydrostatic pressure, ↓ oncotic pressure, lymphatic blockage, Na+ retention.
  • DIC features widespread microthrombi and subsequent bleeding_._

Continue reading on OnCourse

Sign up for free to access the full lesson, plus unlimited questions, flashcards, AI-powered notes, and more.

CONTINUE READING — FREE

or get the app

Rezzy AI Tutor

Have doubts about this lesson?

Ask Rezzy, our AI tutor, to explain anything you didn't understand

Practice Questions: Hemodynamic Disorders

Test your understanding with these related questions

Which of the following conditions is primarily associated with stasis as a cause of thrombosis?

1 of 5

Flashcards: Hemodynamic Disorders

1/10

_____ and turbulence of blood flow increases risk for thrombosis

TAP TO REVEAL ANSWER

_____ and turbulence of blood flow increases risk for thrombosis

Stasis

browseSpaceflip

Enjoying this lesson?

Get full access to all lessons, practice questions, and more.

START FOR FREE
Rezzy AI Tutor