Hyperemia (active hyperemia)

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1 Hyperemia (active hyperemia)
Is a localised increase in the blood flow to an organ as a result of active dilatation of its arterioles (active means change in the muscle tone of the vessels) Types: 1-Physiological e.g. muscle exercise 2-Pathological e.g. sites of acute inflammation

2 Venous congestion (passive hyperemia)
Is the local increase of venous blood in an organ due to obstruction in the venous outflow.

3 1-Chronic Venous Congestion of Lung (C.V.C,Lung)
*occurs in mitral stenosis or left sided heart failure. *the lungs are enlarged, firm and reddish brown >> brown induration *M/P the alveolar capillaries are dilated and congested >> rupture with extravasation of red cells that hemolyse with release of hemosiderin >>> phagocytosed by macrophages “Heart failure cells”

4 2-C.V.C , Liver *occurs in right heart failure or constrictive pericarditis *the liver is enlarged, firm with tense capsule *C/S >>alteration of brown(congested) and yellow (fatty change) coloration >> Nutmeg liver *M/P the central veins are dilated and congested.The centrizonal hepatocytes undergo pressure atrophy , and necrosis.The peripheral hepatocytes show fatty change.

5 3-C.V.C , Spleen *occur in impaired portal venous drainage as in cirrhosis or right side heart failure *the spleen in enlarged, firm with thick capsule.The cut surface is dark red. *M/P the splenic sinuses are dilated, congested and ruptured with the appearance of hemosiderin-laden macrophages followed by fibrosis >> Gamna-Gandy nodules.

6 Hemorrhage Definition :
the escape of blood outside the blood vessels or cardiac chambers Causes: 1-trauma. 2-diseases of the vascular wall e.g. atherosclerosis or aneurysm. 3-destruction of the vascular wall by tuberculosis, peptic ulcer or malignancy.

7 4-increased intravascular tension e. g
4-increased intravascular tension e.g. chronic venous congestion and hypertension. 5-hemorrhagic blood diseases as hemophilia. 6-vitamin C and K deficiency. Types: 1-External hemorrhage There is escape of blood outside the body a)Epistaxis :bleeding from the nose. b)Hemoptysis :coughing of blood. c)hematemesis:vomiting of blood.

8 II-Internal hemorrhage
d)Melena :presence of dark digested blood in stool. e)Hematuria :presence of blood in urine. f)Menorrhagia : excessive or prolonged menstrual bleeding . II-Internal hemorrhage There is escape of blood inside the body cavities. a)Hemothorax: bleeding into the pleura. b)Hemopericardium :bleeding into the pericardium

9 III –Interstitial hemorrhage
c)Hemoperitoneum : bleeding into the peritoneum d)Hemoarthrosis : bleeding into the joint cavity. e)Hematocele : bleeding into the tunica vaginalis. III –Interstitial hemorrhage There is escape of blood into the interstitial tissue spaces a)Petechiae : minute hemorrhage of capillary origin

10 b)Purpura :hemorrhage slightly larger than petechiae
c)Ecchymosis : hemorrhage larger than purpura (1-2 cm in diameter) d)Hematoma : large accumulation of blood within body tissues.

11 Ischemia Definition An inadequate flow of blood to a part of the body caused by constriction or blockage of the supplying blood vessels.

12 I- Acute (sudden) ischemia
Types I- Acute (sudden) ischemia Causes of sudden complete vascular occlusion : 1) Thrombosis or embolism (commonest) 2) Surgical ligature of the artery. 3) Twisting of the pedicle of a mobile organ e.g. intestinal loop. 4) Arterial spasm.

13 II- Chronic (gradual) ischemia
Causes of gradual incomplete vascular occlusion : 1) Atherosclerosis 2) Pressure from outside by tumor or enlarged LN Effects : 1- With inefficient collaterals >>> infarction 2- With efficient collaterals >>> no tissue damage

14 Edema the accumulation of abnormal amounts of fluid in the intercellular tissue space or body cavities. Anasarca severe and generalized edema. Hydropericardium the accumulation of edema fluid in the pericardial cavity. Hydrothora the accumulation of edema fluid in the thoracic cavity. Hydroperitoneum or Ascites the accumulation of edema fluid in the peritoneal cavity.

15 Causes of edema 1-Increased intravascular hydrostatic pressure:
a) congestive heart failure. b) impaired venous flow as in cases of external compression as by tumors 2-Reduced plasma colloid osmotic pressure: a) excessive loss of albumin e.g., nephrotic syndrome b) decreased synthesis of albumin e.g., malnutrition.

16 3-Lymphatic obstruction :
a) inflammatory or neoplastic obstruction. b) fibrosis of lymph nodes and lymphatics e.g., filariasis 4-Sodium and water retention: as in congestive heart failure. 5-Increased vascular permeability: a) inflammation. b) trauma, allergic reactions.

17 Classification of Edema
A)Generalized : 1- congestive heart failure. 2- nephrotic syndrome. B)Localized : 1- venous obstruction due to external compression by pregnant uterus. 2- lymphatic obstruction. 3- increased vascular permeability.

18 Edema also is classified into :
A-Soft (pitting ) edema: The affected edematous part pits on pressure as in cardiac failure, renal failure or malnutrition

19 Other types of edema B-Hard (non-pitting) edema:
The edematous part does not pit on pressure(edematous fluid is united with tissue elements) as in lymphatic edema. Other types of edema a)Dependent edema: Subcutaneous edema of lower limbs and sacral edema because distribution of edema is influenced by gravity.

20 b)Periorbital edema : as in renal dysfunction.

21 SHOCK (circulatory collapse)
Definition A widespread hypoperfusion of cells and tissues due to reduction in blood volume or cardiac output. * Reversible * But with prolonged shock >>> irreversible tissue injury and often fatal

22 Classification of shock
A) Cardiogenic shock Causes Coronary artery occlusion or myocardial infarction Rupture of a valve cusp Arrhythmia Cardiac tamponade Pulmonary embolism

23 C) Septic (endotoxic) shock
B) Hypovolemic shock Causes Severe hemorrhage Fluid loss e.g., severe vomiting, diarrhea and burns C) Septic (endotoxic) shock Severe fungal or bacterial infections : * Gram-negative organisms as E.coli * Gram-positive organisms as streptococci and pneumococci

24 D) Neurogenic shock E) Anaphylactic shock Causes 1. Anesthesia
2. Brain stem or spinal cord injury E) Anaphylactic shock with hypersensitivity reactions

25 THANKS Dr/Mona Kamal