Lab Values & Bleeding Disorders Flashcards
What is normal hemoglobin range?
12-18g/100mL
What is normal hematocrit?
35-50%
What is a normal RBC count?
4-6 million/mm3
What is a normal WBC count for an infant?
8,000-15,000/mm3
What is a normal WBC count for a 4-7 year old?
6,000-15,000/mm3
What is a normal WBC count for an 8-18 year old?
4,500-13,500/mm3
What is a normal ANC?
> 1500/uL
What defines neutrophilia?
ANC > 7,000/uL
What defines neutropenia?
ANC < 1,000/uL
At what ANC should elective dental care be deferred?
ANC < 1,000/uL
At what ANC should antibiotic prophylaxis be provided before dental care?
ANC < 2,000/uL
What is a normal platelet count?
150-450k/mL
What test evaluates the extrinsic clotting cascade?
prothrombin time (PT)
What test evaluates the intrinsic clotting cascade?
partial thromboplastin time (PTT)
What is the MOA of anticoagulation of warfarin?
Inhibition of Vitamin K reductase involved in synthesis of factors II, VII, IX, X
What is the MOA of anticoagulation of heparin?
Blocks inhibitory binding site on antithrombin III enzyme to keep it actively degrading thrombin
What is the MOA of anticoagulation of eliquis?
Direct inhibitor of factor Xa
What is the MOA of anti-platelet effects of aspirin?
Irreversible inhibition of COX-1, blocking thromboxane synthesis.
What type of hemoglobin is seen in sickle cell disease?
Hemoglobin S
What is the life span of sickle cell red blood cell?
10-20 days
What is the 10/30/50 rule for elective dental surgery?
Hemoglobin = 10+
Hematocrit = 30% +
Platelet count = 50k +
What medication are sickle cell patients often taking?
folic acid - helps in proliferation of new RBCs
To what age do children with sickle cell disease take daily penicillin to prevent infection?
6 years
What occurs in sickle cell crisis?
sickle RBCs block blood flow to bones and results in intense pain that can last hours - days
What occurs in aplastic crisis?
a stop in the production of RBCs
Why do you have to be aware of ischemia in sickle cell patients?
can cause tooth pain without the presence of dental caries
T/F: nitrous oxide use is contraindicated in patients with sickle cell disease
False
What test is prolonged by vitamin K deficiency?
PT (extrinsic pathway)
What test is prolonged by hemophilia and von willebrands disease?
PTT (intrinsic pathway)
Why can’t patients with bleeding disorders take NSAIDs or aspirin?
they both inhibit COX which decreases platelet aggregation and causes bleeding
What metabolizes NSAIDs?
kidney
What metabolizes acetaminophen?
liver
What occurs in von willebrands disease?
deficiency in von willebrand factor affecting platelet adhesion
What factor is deficient in hemophilia A?
Factor VIII
What factor is deficient in hemophilia B?
Factor IX
What factor is deficient in hemophilia C?
Factor XI
How is hemophilia inherited?
X-linked recessive
What is considered mild hemophilia A?
5-25% factor activity
What is considered moderate hemophilia A?
1-5% factor activity
What is considered severe hemophilia A?
<1% factor activity
What treatment is given to treat von willebrand?
humate P and desmopressin
What treatment is given for Hemophilia A?
Desmopressin and/or recombianant factor VIII
What treatment is given for hemophilia B?
Benefix
How is recombinant factor provided to patients undergoing surgical procedures?
1 infusion gives 60-80% recovery for minor surgeries, repeated every 8-24 hours for major surguries
What is Avitene?
topical agent that attracts platelets and triggers aggregation to produce fibrin
What is the MOA of aminocaproic acid (Amicar) and Tranexamic acid (Cyclokapron)?
inhibit fibrinolysis mechanism by blocking the binding site of plasminogen
What cannot be given to a hemophilia patient for pain control?
NSAIDs or Aspirin
