Pathology: Haemodynamic Disorders and Hemostasis

This set of vocabulary flashcards covers key concepts in pathology including haemodynamic disorders, fluid balance, sodium and potassium regulation, haemostasis, thrombosis, embolism, infarction, edema, and shock.

Haemodynamic Disorders

Disorders relating to the flow of blood within the organs and tissues of the body, including water, minerals, and the whole blood.

Osmolality

The ratio of total body solute in total body water, regulated to be at a constant level between $280\text{--}295\,mOsm/kg$.

Arginine Vasopressin (ADH)

A hormone activated by pain, stress, volume, and thirst sensors that acts on the collecting ducts to reabsorb water and concentrate urine.

Isonatremic Dehydration

A type of dehydration that does not affect the concentration of sodium in the extracellular fluid, also known as isotonic or iso-osmolar dehydration.

Hyponatremia

A condition referring to a serum sodium level under $130\,mmol/l$, often caused by dilution from excess water or increased sodium loss.

Hypernatremia

A condition referring to a serum sodium level greater than $150\,mmol/l$, indicative of an absolute or relative water deficit.

Hypokalemia

A reduction of serum potassium to less than $3.5\,mmol/l$, which can be caused by redistributional shifts or renal and gastrointestinal losses.

Hyperkalemia

An increase in serum potassium, which may be caused by reduced excretion in renal failure, potassium-sparing diuretics, or cell destruction.

Haemostasis

A synergistic mechanism through which the body controls bleeding and prevents thrombosis using blood vessels, platelets, and coagulation factors.

Thrombus

A coagulated solid mass composed of blood constituents including platelets, fibrin, WBCs, and RBCs that develops in an artery, vein, capillary, or heart chamber.

Virchow’s Triad

The three factors responsible for the pathogenesis of thrombosis: damage to the endothelial lining, abnormal blood flow (stasis or turbulence), and increased blood coagulability.

Lines of Zhan

Alternating white (platelets and fibrin) and red (RBCs) lines found in large thrombi formed in a living person.

Embolism

The passage of solid, liquid, or gaseous material in blood vessels capable of obstructing blood flow distal to the site of insertion.

Saddle Embolus

A large thrombus that blocks the outflow tract of the right ventricle or the bifurcation of the main pulmonary trunk, potentially causing sudden death.

Infarction

A process in which ischemic necrosis develops in an area after the occlusion or rupture of an artery by an embolus, thrombus, spasm, or torsion.

Red Infarcts (Hemorrhagic)

Infarcts occurring in venous occlusions, loose tissues like the intestine, or tissues with dual circulation such as the lung and liver.

White Infarcts (Anaemic)

Infarcts occurring due to arterial occlusion in solid organs with a single arterial blood supply, such as the heart, spleen, and kidney.

Edema

The abnormal accumulation of fluid in the interstitial spaces of organs or body cavities, clinically manifesting as swelling.

Starling’s Law

A law stating that the accumulation of interstitial fluid is regulated by the balance between hydrostatic pressure, oncotic pressure, and the permeability of vessels.

Pitting Edema

A type of peripheral edema where pressure applied to a small area results in an indentation that persists after the pressure is released.

Lymphedema

An abnormal accumulation of interstitial fluid caused by an obstruction of the lymphatic system, such as from cancer, radiotherapy, or parasites.

Shock

A clinical state of systemic hypoperfusion characterized by progressive cardiovascular collapse, reduced cardiac output, and effective circulating blood volume.

Cardiogenic Shock

Shock resulting from severe depression of cardiac performance, primarily pump failure of the left or right ventricle, most commonly due to myocardial infarction.

Septic Shock

A subtype of distributive shock caused by serious bacterial infections where endotoxins induce vasodilation and increased capillary permeability.

Hyperemia

An active process resulting from increased blood flow into a tissue due to arteriolar vasodilation, causing the tissue to become red.

Congestion

A passive process resulting from impaired outflow of blood from a tissue, causing it to appear blue-red due to deoxygenated blood accumulation.

Nutmeg Liver

The gross appearance of the liver in chronic passive hepatic congestion, where central zones appear red-brown and portal zones appear tan.

Atherosclerosis

Developing intimal thickened lesions, such as fatty streaks and fibrofatty plaques, leading to complications like thrombosis, embolism, or aneurysm.