Hemodynamic Disorders covers hemodynamic disorders for INI CET (AIIMS PG).
Edema: Abnormal fluid accumulation in interstitial spaces or body cavities.
Types of Edema:
- Localized edema: DVT (unilateral leg swelling), allergic reactions (angioedema), lymphatic obstruction
- Generalized edema: Anasarca (severe generalized), peripheral pitting edema
Pathogenesis (Starling forces):
- Increased capillary hydrostatic pressure: Heart failure, renal failure
- Reduced plasma oncotic pressure: Hypoalbuminemia (liver disease, nephrotic syndrome)
- Increased capillary permeability: Inflammation, burns
- Lymphatic obstruction: Lymphedema (elephantiasis)
Pitting Edema Test: Press skin over tibia for 5 seconds — if indentation persists = pitting edema (fluid-filled, not fatty)
Hyperemia and Congestion:
- Active hyperemia: Arterial inflow increases (inflammation, exercise) — bright red
- Passive congestion: Venous outflow decreases — dark red-blue (liver, lungs)
- Chronic venous congestion (CVC) of liver: Nutmeg liver (dilated central veins, atrophic hepatocytes, hemorrhage)
- Pulmonary congestion: Brown induration (hemosiderin-laden macrophages = “heart failure cells”)
Hemorrhage:
- Petechiae: 1–2 mm (platelet disorders, infections)
- Purpura: 3–10 mm
- Ecchymosis: >10 mm (bruise)
- Hemothorax/Hemopericardium/Hemoperitoneum: Blood in body cavities
Shock: Inadequate tissue perfusion leading to cellular hypoxia. Types:
| Type | Mechanism | Example |
|---|---|---|
| Hypovolemic | Blood/fluid loss | Hemorrhage, severe dehydration |
| Cardiogenic | Pump failure | MI, cardiac tamponade |
| Distributive (Septic) | Vasodilation + maldistribution | Sepsis, anaphylaxis, neurogenic |
| Obstructive | Mechanical obstruction | PE, tension pneumothorax |
⚡ Exam Tip for INI CET (AIIMS PG): In septic shock, TNF-α and IL-1 cause vasodilation → warm shock (warm extremities early). In hypovolemic shock → cold extremities. Knowing this difference is critical for clinical diagnosis.