6 Fluid & Vascular Disturbances Flashcards

Flashcards about Fluid & Vascular Disturbances

Oedema

An abnormal accumulation of fluid in intercellular spaces or within body cavities.

Ascites

Oedema in peritoneum.

Hydrothorax

Oedema in thoracic cavity.

Hydropericardium

Oedema in pericardium.

Hydrocoele

Oedema in tunica vaginalis.

Anasarca

Generalized oedema.

Hydrops or Hydrops foetalis

Generalized oedema.

Transudate

Non-inflammatory tissue fluid with little protein content.

Exudate

Inflammatory fluid with high protein content.

Lymphatic obstruction

Prevention of normal drainage of tissue fluid (i.e. transudate).

Impaired venous drainage

Increased venous hydrostatic pressure (increased pressure within lumen of vein, so fluid moves into tissue space).

Malnutrition (e.g., Kwashiorkor)

Decreased plasma protein levels leading to disrupted Starling forces.

Haemorrhage

Loss of blood from the circulation.

Haemostasis

The physiological process preventing blood loss from the circulation.

Intrinsic pathway

Coagulation initiated by contact with surface agents such as collagen or proteases, acting through Factor XII (Hageman factor).

Extrinsic pathway

Coagulation initiated by Tissue Factor (generated from damaged tissues) and its interaction with Factor VII.

Common pathway

Series of steps that leads to generation of cross-linked fibrin.

Plasminogen

Inactive form in blood that converts to plasmin (active enzyme which dissolves fibrin).

Hypovolaemia

Decreased blood volume; Main effect of haemorrhage.

External haemorrhage

Blood lost to the exterior of body (e.g. bleeding into GI tract).

Internal haemorrhage

Blood lost into tissue or internal body cavities (e.g. bleeding into pleura).

Petechiae

Very small spots of haemorrhage - from microvasculature.

Haematoma

Large haemorrhage, “bruise” - from larger vessels.

Ecchymosis

Very large haematoma - patient on anticoagulants.

Diathesis

Predisposition or tendency to suffer from a disease.

Haemophilia A

X-linked recessive, deficiency of factor VIII, leading to bleeding.

Purpura

Disorder in which multiple small, purplish bruises develop on the skin or mucosal surfaces (i.e. petechiae/petechial haemorrhages).

Thrombocytopenia

Platelet count <100,000 platelets/µL blood.

Non-thrombocytopenic purpura

Vascular defects, normal platelet numbers.

Thrombasthenia

Platelets are abnormal in function.

Shock

A low perfusion circulatory insufficiency leading to an imbalance between the metabolic needs of the tissues and the blood available to perfuse them.

Primary shock

Low blood pressure mediated by a transient neurovascular reaction, often leading to fainting.

Secondary shock

Disturbance of fluid balance leading to decreased blood volume and renal functional deficiency.

Hypovolaemic shock

Shock due to haemorrhage, plasma loss (burns), fluid/electrolyte loss (sweating, diarrhoea).

Cardiogenic shock

Shock due to cardiac diseases (e.g. heart attack), respiratory disorders affecting heart (e.g. respiratory failure).

Septic shock

Shock due to septicaemia (Gram -ve bacteria), causing the production of endotoxin.

Thrombosis

The process resulting in the formation of a solid or semi-solid mass composed of blood constituents, within the circulation during life.

Thrombus

The resulting mass from thrombosis.

Pale (white) thrombi

Thrombi composed of platelets and fibrin forming in fast flowing blood.

Dark (red) thrombi

Thrombi composed of fibrin, red & white blood cells forming in static blood.

Mixed (laminated) thrombi

Thrombi composed of regions of platelets/fibrin, and RBC/WBC/fibrin forming in slow flowing blood.

Mural Thrombi

Adherent to one side of vessel wall, lumen not completely obstructed.

Occlusive Thrombi

Lumen totally obstructed.

Coralline Thrombi

Irregular, can become occlusive.

Propagating Thrombi

Progressive involvement of thrombus into other vessel branches.

Ball Thrombi

Unattached spherical thrombus.

Septic Thrombi

Presence of infection.

Vegetations

Thrombi on heart valves.

Virchow’s Triad

Changes in the vessel wall, blood flow, and blood constituents that predispose to thrombosis.

Propagation (of a thrombus)

Thrombus enlarges along a vessel, involving more branches.

Lysis and Resolution (of a thrombus)

Thrombus undergoes lysis by fibrinolytic system.

Calcification (of a thrombus)

Dystrophic calcification of thrombus.

Retraction, Organization, Recanalization (of a thrombus)

Granulation tissue forms, re-establishing blood flow through scar tissue.

Thromboembolism

Detachment of thrombus or small fragment, travelling to distant location.

Infarction

Interruption of blood flow due to a thrombus, leading to anoxia and necrosis of tissue.

Embolism

Occlusion of a vessel by a mass of material that is transported in the bloodstream.

Venous Emboli

Most commonly arise in the deep leg or pelvic veins and lodge in the pulmonary vessels.

Arterial Emboli

Most commonly arise in aorta, coronary & cerebral arteries due to atherosclerosis complicated by thrombosis and may lodge in any organ.

Bone fracture fat emboli

Severe bone fracture trauma may tear thin walled veins and allow marrow fat to enter bloodstream; may lodge in lungs & brain.

Atherosclerotic plaque fat emboli

Lipids from atheromatous plaques may enter bloodstream.

Air emboli

Most commonly arise in veins due to faulty IV therapy technique, complicated childbirth, open heart surgery.

Nitrogen emboli

Arise throughout circulation due to deep sea divers ascending too quickly to the surface.

Foreign body embolism

Needles, wood splinters, talc grains, tubing, catheter tips, acrylic bone cement due to IV drug use, faulty therapy techniques.

Tumour embolism

Usually arise in venules or veins due to malignant tumour infiltrating through the wall of a blood vessel.

Amniotic fluid embolism

Amniotic fluid enters maternal circulation via bleeding placental bed and travel to lung capillaries during childbirth.