Hematology Flashcards
4 steps to Hemostasis:
- Vascular spasm
- Formation of platelet plug (primary hemostasis)
- Coagulation and formation of fibrin (secondary hemostasis)
- Fibrinolysis when clot is no longer needed.
Name the Procoagulants:
- Factors I-XIII
- Fibrinogen
- vWF
- Fibronectin
Patients with von Willebrand disease bleed more readily due to
A. inhibition of thromboxane A2 production
B. inactivation of platelet cyclooxygenase
C. decreased factor eight activity
D. Factor X deficiency
C. decreased factor eight activity
Von Willebrand factor (vWF) is responsible for carrying factor VIII and serves to help link platelets. Patients with von Willebrand disease have a prolonged bleeding time, low plasma vWF concentration, and decreased factor VIII activity. Aspirin inhibits the production of thromboxane A2. Aspirin and other NSAIDs acetylate and inactivate platelet cyclooxygenase. Aspirin inactivates cyclooxygenase for the life of the platelet but other NSAIDs inactivate reversibly and the effect lasts only about 24 hours. Factor X deficiency is Stuart-Prower deficiency and is unrelated to von Willebrand disease.
Which of the following values may be elevated in patients with disseminated intravascular coagulation?
A. Fibrinogen B. Platelet count C. Factor VIII D. D-dimer
D-dimer
The PT, PTT, thromboplastin time, D-dimer, and fibrin degradation products are all elevated in patients with acute DIC.
Hemophilia B can be treated with
A. factor VII concentrate B. factor VIII concentrate C. factor IX concentrate D. desmopressin and cryoprecipitate
C. factor IX concentrate
Hemophilia B (also called Christmas disease) is treated with factor IX concentrate. Hemophilia A can be treated with desmopressin, cryoprecipitate, and factor VIII concentrate. Congenital factor VII deficiency is known as Alexander’s disease or proconvertin deficiency. Severe liver disease is also associated with an acquired factor VII deficiency.
Which form of hemoglobin is most commonly found in the normal, adult bloodstream?
A. Hemoglobin A B. Hemoglobin C C. Hemoglobin F D. Hemoglobin S
hemoglobin A
Hemoglobin A comprises about 97% of all the hemoglobin found in the normal, adult bloodstream. Hemoglobin C is implicated in a type of hemolytic anemia, hemoglobin F is found in fetuses, and hemoglobin S is found in patients with sickle cell anemia.
Which of the following conditions does not lead to an elevated hematocrit?
A. Chronic hypertension B. Polycythemia C. Dehydration D. Sickle cell crisis
D. Sickle cell crisis
Chronic hypertension leads to a contracted fluid volume status, which results in a concentration of the red blood cells in a smaller space, thereby increasing the hematocrit. Polycythemia is a condition resulting in an elevation of the hematocrit due to an overproduction of red blood cells. Dehydration also concentrates the red blood cells in a smaller fluid space, resulting in an increased hematocrit. Sickle cell results in the destruction of red blood cells which lowers the hematocrit.
Which of the following is false regarding disseminated intravascular coagulation?
A. It usually occurs as a result of septic shock due to gram-negative organisms
B. It may occur as a result of prolonged surgery
C. It may occur as a result of placenta previa
D. It may occur in association with tumor lysis syndrome
A. It usually occurs as a result of septic shock due to gram-negative organisms
DIC is associated with a wide range of disorders including septic shock, placenta previa, abruption, amniotic fluid embolism, presence of a dead fetus late in pregnancy and tumor lysis syndrome. Prolonged surgery and surgery for certain procedures such as prostatectomy for carcinoma, liver transplantation, and coronary bypass surgery are associated with significant bleeding abnormalities. When associated with septic shock, it is most often caused by gram-positive organisms.
Which of the following statements regarding hemophilia is FALSE?
A. Hemophilia A is a sex-linked disorder
B. Hemophilia B is also known as Christmas disease
C. Patients with hemophilia A are deficient in factor VIII
D. Factor VIII is known as Christmas factor
D. Factor VIII is known as Christmas factor
Hemophilia A is a sex-linked deficiency of factor VIII that is carried on the X chromosome. Hemophilia B results from a decreased level of factor IX, also known as Christmas factor.
Which of the following drugs would not be safe for use in the anesthetic management of a patient with acute porphyria?
A. Nitrous oxide B. Neostigmine C. Morphine D. Ketorolac
D. Ketorolac
Nitrous oxide, neostigmine, morphine, fentanyl, succinylcholine, pancuronium, lidocaine, and propofol are considered safe for use in patients with porphyria. Ketorolac, thiopental, thiamylal, etomidate, pentazocine, methohexital, and nifedipine should all be avoided.
