| Question | Answer |
| Hematopoietic system componenets | Erythrocytes (RBC), Leukocytes (WBC), Platelets, Plasma |
| Red Blood Cells | Contains hemoglobin and carries oxygen, biconcave in shape, accounts for 1-2% of red cells in blood. |
| White Blood Cells | Primarily responsible for immune protection, Absolute WBC count often not highly specific of sensitive in the diagnosis of diseases. |
| WBC Differential | (Percentage of different types of WBCs) can be more helpful in determining presence of active infection. |
| Platelets | Primarily responsible for hemostasis, initial defense mechanism for acute blood loss, circulatory life span of 9-10 days, contains proteins on the surface that allow them to stick together. |
| Plasma | Yellowish, liquid component of whole blood, comprises of 55% of total blood volume, composed of 92% water by volume, contains dissolved proteins, ions, and clotting factors. |
| Anemia | An absolute or relative decrease in the number of circulating, functional RBCs |
| Polycythemia/erythrocytosis | An absolute or relative increase in the number of circulating RBCs |
| Thrombocytopenia | An absolute or relative decrease in the number of circulating, functional platelets. |
| Thrombocytosis | An absolute or relative increase in the number of circulating, functional platelets. |
| Leukopenia | An absolute or relative decrease in the number of circulating, functional WBCs. |
| Leukocytosis | An absolute or relative increase in the number of circulating functional WBCs. |
| Components of Hemostasis | Vascular integrity
platelet function
Coagulation factors
Fibrinolysis |
| Bleeding time | measures time between skin incision and cessation of bleeding, normal= 3-8 minutes |
| Platelet Count | Reported as part of complete blood count (CBC), normal= 150,000-400,000/mm. |
| Prothrombin Time (PT) | Evaluates function of extrinsic pathway of coagulation cascade, normal control values= 11-13 seconds. |
| International Normalized Ratio (INR) | Calculated from PT ratio that would have been obtained if the world health organizations reference thromboplastin had been used in measurement of PT. |
| INR also does what? | Allows monitoring of anticoagulation effects if Coumadin. |
| INR therapeutic range depends on reson for anti-coagulation | Atrial fibrillation, biological valve replacement, prevention of DVT/VTE = 2.0-3.0
Mechanical valve replacement, recurrent systemic VTE = 2.5-3.5 |
| Partial thromboplatin time (PTT) | test all factors except VII and XIII, but used primarily to evaluate intrinsic pathway |
| PTT Normal value | Normal= 25-35 |
| Thrombin time | Evaluates ability of fibrinogen (Factor I) to convert into a fibrin clot |
| Thrombin time normal value | < 22 seconds, heparin therapy
-inhibits fibrin formation |
| Heparin has no: | Fibrinolytic capacity
CAN BE REVERSED BY PROTAMINE SULFATE |
| tPA...? | Tissue plasminogen activators (tPA, rtPA) |
| tPA does what? | Catalyzes conversion of plasminogen to plasmin
- Major enzyme responsible for clot degradation
Can result in bleeding in sites other than desired location |
| FFP...? | Fresh Frozen Plasma |
| FFP contains what? | Contains all coagulation factors except platelets. Used for treatment of a pt with an unknown or undiagnosed bleeding disorder with clinically significant active hemorrhage |
| Platelets indicated for what? | Indicated for pt's with bleeding due to thrombocytopenia or platelet dysfunction |
| Typical adult dose of a 6-unit pack of platelets will raise platelet count by about...? | 50,000/mm3 |
| Willebrands disease = | Factor VIII containing vWF (Humate-P or Koate HS) |
| Jaundice caused by what... | Buildup of bilirubin in circulatory system
may also indicate increased hemolysis of RBCs |
| Anemia is what...? | an absolute decrease in the number of circulating RBCs |
| Mayor function of RBC is to...? | Transport oxygen |
| Anemia is classified into three casual categories: | Increased RBC destruction
Decreased RBC production
Acute or chronic blood loss |
| Causes INTRINSIC or EXTRINSIC to RBC cell membrane | INTRINSIC-
Enzyme defects, Membrane abnormality, Hemoglobin abnormality
EXTRINSIC-
Immunologic, mechanical, environmental, abnormal sequestrations |
| Sickle Cell- | Most common hemoglobinopathy encountered in american emergency departments, affects predominantly person of african ancestry |
| Sickle cell patho- | Causes an interlocking with an adjacent hemoglobin chain in the deoxygenated state, leading to the "sickling" of the entire RBC |
| Sickled cells cause and are what? | Cause an increase in viscosity, are less deformable and do not pass through microcirculation, and are sequestered and destroyed the the liver and spleen |
| Sickle cells S&S: | Pt's most often present with symptoms related to a vaso-occlusive crisis and associated sequelae |
| Sickle cell: Vaso-occlusive Crisis- | Severe in extremities, back, joints, abdomen, or chest. Treatment is analgesics and fluid replacement if clinically dehydrated. |
| Hemolytic Crisis treatment: | Similar to vaso-occlusive crisis but includes treatment for potential shock state, may require blood transfusion if symptomatically anemic. |
| Priaprism is what? | Sustained, painful pathologic erection, occurs in 10-40% of male's with sickle cell, can result in impotence. |
| Priaprism treatment? | Immediate urologic consultation, terbutaline 0.25-0.5 mg SQ (reduces blood flow to the penis and other end-organs), Hydration, Analgesia (comfort only) and pRBC transfusion |
| Acute Chest Syndrome accounts for... | 25% of premature deaths in patients with sickle cell disease. |
| Acute Chest Syndrome Tx: | No definitive therapy identified,
supportive care
-Hydration
-Analgesia
-Maintenance of oxygen and ventilation
-Empiric antibiotics |
| Thrombocytopenia is what? | Decreased production of platelets
- Due to bone marrow suppression from variety of causes |
| Immune thrombocytopenia is what? | Increased destruction due to an antiplatelet antibody
Can be related to various other immunilogic disorders such as lupas, leukemia, lymphoma, etc. |
| Heparin-induced thrombocytopenia (HIT): | -Immune-mediated side effect
Occurs in 1-5% of pts receiving heparin
-Usually occurs within 5-7 days of first dose
-Diagnosis is suggested by absolute thrombocytopenia or a >50% reduction in platelets after beginning therapy
-Mortality up to 30% |
| Disseminated Intravascular Coagulation (DIC): | -Relatively common acquired coagulopathy
-Most often encountered in critical care setting |
| DIC potential causes: | -Trauma (burns, crush injuries, TBI, etc)
-Pregnancy complications
-Sepsis
-Transfusion of drug reaction
-Envenomation
-Heat stroke |
| DIC | Out of control coagulation of fibrinolytic cascade within systemic circulation |
| DIC- lifethreatening combination of: | Bleeding tendency
-Loss of platelet and remaining platelet dysfuction
-loss of coagulation factors
-fibrinolysis
Fiberin deposition
-Small vessel obstruction
-Tissue ischemia
RBC injury and resulting anemia |
| Diseases of Hemophilia A | caused by a genetic variant of factor VIII
-present in normal levels but lacks procoagulant properties
-Abnormal gene carried on X chromosome |
| Hemophilia A:Female carriers can have the following possible offspring with each pregnancy | -female carrier
-female without carrier trait
-male with hemophilia A
-male without hemophilia A |
| Hemophilia A: Males with hemophilia A can have the following possible offspring | -All daughters will be carriers
-None of the sons will have hemophilia |
| Hemophilia treatment: | Desmopressin (DDAVP) can be used to increase levels of Factor VIII in pts with mild Hemophilia A and is treatment of choice
-Dose is 0.3mcg/kg intranasally, IV or SQ |
| Hemophilia B: | Caused by genetic decrease in function of factor IX |
| Hemophilia B treatment: | |
| Malignant Pericardial Tamponade: | -Most often caused by pericardial effusiions
-Most common primary malignancies
*Lung
*Breast
*Esophagus
*Leukemia
*Melanoma
-Can result from radiation therapy to chest |
| Malignant Pericardial Tamponade treatment: | -Initial treatment of pericadiocentesis with (or without, but more risky) ultrasound guidance can be lifesaving
-Acts as a bridge to pericardial window in operating room |
| Hernation Syndromes | -Uncal herniation
-Central herniation
-Tonsillar herniation |
