bleeding disorders Flashcards
Petechiae
– pinpoint hemorrhages
–> scurvy “petechial rash” vitamin c deficiency
Purpura
– larger than a pinpoint, but
Ecchymoses
– bruises > 2 cm
types of ecchymoses
- cushing’s syndrome (overproduction of corticosteroids from adrenal cortex)
- raccoon sign
- battle sign
hematoma
- leak of blood into cavities or into tissues (i.e. muscle belly)
- rupture of middle meningeal artery—> epidural hematoma
Hemorrhagic Disorders
- Thrombocytopenia
- Von Willebrand’s disease
- hemophilia
Thrombocytopenia
o Normal amount of platelets in blood: 250,000 – 300,000 o
Von Willebrand’s Disease
- Do not produce von Willebrand factor (no platelet activation, cannot form plug
- hereditary only
- Menorrhagia (increased blood loss during period)
Hemophilia →
- non-production of certain protein clotting factors
- X chromosome linked – females pass the trait to their sons
- 2 types
hemophilia A
non production of CF 8
hemophilia B
- AKA christmas disease
- nonproduction of christmas factor CF 9
hemoarthritis
- blood in joint
- iron in hemes destroy going cartilage
- joint degeneration
hemodynamic Disorders
Disorders that arise from interruptions in normal blood flow
Thrombosis (thrombus formation)
platelet activation and platelet aggregation
without threat of blood loss or vascular damage; platelet plug without blood clot
Blood clot
can be formed inside and/or outside of a vessel
Thrombus
always originates from a vascular wall and always maintains
point of contact with the vascular wall through von Willebrand factor-
platelet activaton and platelet aggregation
Thrombus in the arterial system
Dense and strong , firm and small (fast)
Thrombus in the venous system
Loose and weak , loose and large (slow)
Lines of Zahn
– represent a special type of thrombi characterized by visible and
microscopic laminations produced by alternating layers: pale layer composed of
platelets mixed with fibrin and dark layer composed of RBCs
2 areas where thrombi with lines of Zahn can be found
1- heart
2- aorta (usually in the arch)
mitral stenosis would cause thrombi with lines of Zhan to be formed due to slowed blood flow
Endothelial damage
- hemodynamic stress (normal wear and tear)
– stretching of endothelial cells from the inner surface of
blood vessel collagen fibers are exposed thrombus formed
Hypertension
- increase resistance of the vascular wall to the fluid. Serious factor
that promotes endothelial damage.
Hemodynamic stress
= normal wear and tear resulting in
arteriosclerosis, accelerated and strengthen by hypertension
Artherosclerosis
– specific changes, such as formation of plaque, in arterial walls ..leads to endothelial damage in the arteries.
Artherosclerotic plugs Damaged endothelia cells
Iatrogenic thrombosis
– caused by medical care; e
Myocardial infarction (MI)
– dead heart
tissue heals/scars over with fibrotic tissue
which is non-contractile tissue
decreased cardiac output ..near the
dead/or tissues replaced the death tissure.
Mural thrombus
– thrombi formed in chambers of the heart
Rheumatic heart disease
– mitral stenosis
slows blood flow in the left atrium
thrombus formation likely, usually kills the
patient
Increased blood viscosity
- Psoriatic arthritis
- Polycytemia – increased RBCs (normal = 3 –
5 million/mm3) up to double the normal
amount; increased friction with the
vascular wall; - ex. erythemia – a type of
leukemia
Turbulence (disruption of laminar flow)
May be due to:
- Narrowed portion of lumen
- Expanded lumen, aneurysm
- Twists and turns in a vessel (as seen in varicose veins)
Blood hypercoagulation
– increased ability of the blood to coagulate
o Extensive burns-increase coagulation o Some kidney diseases-usually associated with kidney failure o Heart failure o Widespread metastatic tumor growth-when too many metastatic usually
malignant tumor o Birth control pills due to endocrine imbalance MCC of
hypercoagulation ..promotes artherosclerosis
Sequela/ae (pl.)
– the pathological consequence(s) of an event
White infarct
– develops in tissues that have 1 blood vessel supply
Heart – coronary artery
Red infarct
– when a tissue is supplied by 2+ blood vessels
Lungs – pulmonary artery and bronchial artery
Ischemic stroke (AKA brain infarction)
i. Most common area for stroke ii. Liquefactive necrosis with cavity formation
iii. Neuroglia (neuroglial cells) are responsible for repairing the lost
brain tissue
Gliosis
= process of repair via neuroglia in the brain does not
shrink which is a huge advantage for the brain.
Heart sources of thrombus:
- Mitral stenosis
- Bacterial endocarditis – MCC of ischemic stroke
- Artificial valve – thrombus forms around it
Fat embolism:
-From long bone fracture (in 1 or 2 days) → enters the venous circulation →
travel towards the lungs
-Can cross capillaries and travel in reverse direction to the brain causing
purpuric brain hemorrhages
air embolism
- At least 300ml Gas within the vessels would increase pressure → blockage of fluid flow Air lock – pathology in which air embolism blocks blood flow Bends (aka caisson disease, divers’ disease) – elevation changes and changes
in concentration of nitrogen in blood due to pressure change ; appearance of
gas in blood circulation
