Hematopoietic System: Case 3 Flashcards
Certain elements of the history are particularly useful in determining whether bleeding is caused by:
- an underlying hemostatic disorder
- by a local anatomic defect
One clue is a history of bleeding following common hemostatic stresses such as:
dental extraction, childbirth, or minor surgery
What merits special attention?
Bleeding that is sufficiently severe to require blood transfusion
What suggests a systemic disorder?
A family history of bleeding and bleeding from multiple sites that cannot be linked to trauma or surgery
Since bleeding can be mild, lack of a family history of bleeding does not exclude an inherited hemostatic disorder.
This is usually localized to superficial sites such as the skin and mucous membranes, comes on immediately after trauma or surgery, and is readily controlled by local measures.
Bleeding from a platelet disorder
Differences in the Clinical Manifestations of Disorders of Primary and Secondary Hemostasis
Primary
Platelet Defects
Onset of bleeding after trauma: Immediate
Sites of bleeding: Superficial— skin, mucous membranes, nose, GI and genitourinary tracts
Physical findings: Petechiae, ecchymoses
Family history: Autosomal dominant
Response to therapy: Immediate; local measures effective
Secondary
Plasma Protein Defects
Onset of bleeding after trauma: Delayed — hours or days
Sites of bleeding: Deep — joints, muscle, retroperitoneum
Physical findings: Hematomas, hemarthroses
Family history: Autosomal or X-linked recessive
Response to therapy: Requires sustained systemic therapy
In contrast, bleeding from plasma coagulation defects occurs when?
hours or days after injury and is unaffected by local therapy. Such bleeding most often occurs in deep subcutaneous tissues, muscles, joints, or body cavities.
● A thorough history may establish presence of a hemostatic disorder and guide initial laboratory testing.
The most common site to observe bleeding is in the:
skin and mucous membranes
Collections of blood in the skin are called ___________ and may be subdivided on the basis of the site of bleeding in the skin.
Purpura
Small pinpoint hemorrhages into the dermis due to the leakage of red cells through capillaries are called ________ and are characteristic of platelet disorders in particular, severe thrombocytopenia.
Petechiae
Larger subcutaneous collections of blood due to leakage of blood from small arterioles and venules are called:
ecchymoses (common bruises) or, if somewhat deeper and palpable, hematomas
They are also common in patients with platelet defects and result from minor trauma.
What may cause bleeding without any hemostatic defect?
Dilated capillaries, or telangiectasia
In addition, the loss of connective tissue support for capillaries and small veins that accompanies aging increases the fragility of superficial vessels, such as those on the dorsum of the hand, leading to:
extravasation of blood into subcutaneous tissue — senile purpura
What is sometimes a serious problem in women with severe thrombocytopenia or platelet dysfunction?
Menorrhagia
Some patients with primary hemostatic defects, especially von Willebrand’s disease, may have:
- recurrent gastrointestinal hemorrhage
- often associated with angiodysplasia
- a common vascular malformation in the gastrointestinal tract
Bleeding into body cavities, the retroperitoneum, or joints is a common manifestation of:
plasma coagulation defects
What may cause synovial thickening, chronic inflammation, and fluid collections and may erode articular cartilage and lead to chronic joint deformity and limited mobility?
Repeated joint bleeding
Joint deformities are particularly common in patients with deficiencies of factors what?
VIll and IX, the two sex-linked coagulation disorders referred to as the hemophilias.
For unclear reasons, _____________ are much less common in patients with other plasma coagulation defects.
hemarthroses
What can cause secondary necrosis of tissues or nerve compression?
Blood collections in various body cavities or soft tissues
Retroperitoneal hematomas can cause femoral nerve compression, and large collections of poorly coagulated blood in soft tissues occasionally mimic malignant growths:
the pseudotumor syndrome
Two of the most life-threatening sites of bleeding are in the ___________, where bleeding can compromise the airway, and in the central nervous system.
oropharynx
What is one of the leading causes of death in patients with severe coagulation disorders?
Intracerebral hemorrhage
Because of their need for plasma and factor concentrates derived from multiple donors, many patients with hemophilia were infected with:
HIV before effective testing of donors was in place