pathophysiology podcats (ch 9)

Inflammation

localized immune response to injury or infection

Acute inflammation

rapid, short-lived response featuring redness, heat, swelling, pain, and loss of function

Vasodilation

widening of blood vessels increasing blood flow to affected area

Increased vascular permeability

allows plasma proteins and leukocytes to migrate from circulation into tissue

Exudate

protein-rich fluid and immune cells that leak out of blood vessels

Transudate

low-protein fluid caused by imbalanced hydrostatic/osmotic pressures

Margination

movement of leukocytes toward vessel walls

Diapedesis

passage of leukocytes through blood vessel walls into tissues

Chemotaxis

directional movement of leukocytes toward chemical signals at injury site

Neutrophils

first responders to inflammation, phagocytose pathogens and debris

Macrophages

phagocytic cells that clear debris, coordinate repair and immunity

Inflammatory mediators

molecules (e.g., histamine, prostaglandins, cytokines) that regulate inflammatory response

Histamine

mediator from mast cells causing vasodilation and vascular permeability

Prostaglandins

lipid mediators involved in pain, fever, and vasodilation

Cytokines

signaling proteins (e.g., IL‑1, TNF) that regulate immune and inflammatory responses

Fever

elevated body temperature induced by pyrogens acting on hypothalamus

Chronic inflammation

prolonged inflammation featuring tissue destruction and fibrosis

Granuloma

organized cluster of macrophages (often with lymphocytes) in chronic inflammation

Fibrosis

formation of scar tissue through collagen deposition by fibroblasts

Resolution

restoration of normal tissue structure and function after injury

Regeneration

replacement of lost cells with identical tissue

Scar formation

deposition of collagen in wound, replacing normal structures

Wound healing phases

hemostasis → inflammation → proliferation → remodeling

Primary intention

wound edges approximated, minimal tissue loss and scarring

Secondary intention

wound heals with significant tissue loss and granulation, more scarring required.