Answers to Question about the Chapter

Nosebleeds[Epistaxis]

Nosebleeds

• 60% occurrence – ruptured blood vessels

• Most common cause: increased blood pressure

• Cure: waiting for blood to clot– Pinch nostrils together

(Little’s Area)

Nosebleed Factors

Blunt traumaNose-pickingAllergiesDrugs (snorting/Aspirin)AlcoholNasal SpraysHeart ProblemsDry/Not Humid Air

Otic Barotrauma• Damage to body

tissues from difference in pressure

• Ex. An airplane landing

• Underwater in a deep pool

• Going from high pressure to low pressure nosebleed!

Disorders of the Blood

Hemostasis

• Hemostasis – Stoppage of Blood Flow• Three Stages:

1. Platelet Plug Formation (platelets activated)2. Vascular Spasms (serotonin) – Blood vessels

• Decreases blood loss until clotting

3. Coagulation (clotting – platelets and fibrinogen)• Can take 3-6 minutes

Not Enough Hemostasis!!!

Hemophilia and Thrombocytopenia

Hemophilia

• When cut, your blood is unable to clot– Lacks platelets or

fibrinogen• Hereditary• Only found in males• Carrier females ONLY

• Popularly found in royal family members (England and Russia)

Queen Victoria’s Lineage

Thrombocytopenia

• Not enough circulating PLATELETS (blood clotting)

• Small purplish blotches on skin (spontaneous bleeding)

• Can be due to lack of Vitamin K (leafy greens)

• Negatively affect liver function (clotting factors)

Quick Quiz 1 of 2

• What is the MAIN GOAL of hemostasis?

• How is hemophilia different from thrombocytopenia (hint: how do you get it?)

• What can you do to prevent getting thrombocytopenia in your diet?

When Clotting Goes Too Far…THROMBUS

• Persistent clotting in blood vessels

• Can lead to heart attack (pulmonary thrombus)• Embolus = free-floating clot

– Can cause heart attack or stroke!

• Common in immobilized patients (people in comas)– Slowly flowing blood

Heart Attacks and Tylenol• Heart attack (Myocardial

Infarction) – when blood supply to heart blocked off

• Tylenol = anti-coagulant

• Taking one/two pills can increase chances of surviving heart attack

Sickle Cell Anemia

• Anemia – Iron-deficiency due to lack of hemoglobin

• Sickle cells – moon-shaped RBCs

• Less surface area = less hemoglobin = less iron = anemia!

• Hereditary!

Sickle Cell and Malaria

• High prevalence in African Americans, why?

• Malaria – mosquito-borne infectious disease that attacks blood cells– Started thousands of years ago

• 90% deaths from Malaria = Sub-Saharan Africa

• Sickle cells = immune to malaria

Leukemia – “White Blood”

• Cancer of the bone marrow– Most common cancer in children

• Bone marrow = stem cells– Make RBCs, WBCs and platelets

• Stem cells produce immature, abnormal and nonfunctional WBCs in large amounts– Leaves body open to opportunistic infection

• Cure: Bone Marrow transplant (difficult)

Leukemia Post- WWII• 1945 – Atomic Bomb

in Hiroshima– Ending WWII in Japan

• Radiation Cancer (Leukemia)

• Killed 140,000

• Sadako and the Thousand Paper Cranes – Eleanor Coerr

Quick Quiz 2 of 2

• What is the name of the free-floating clot resulting from a thrombus?

• Which cells are DIRECTLY AFFECTED by Leukemia (test question)

• If something is an anti-coagulant (Tylenol), what does that mean?

Artificial Blood Substitutes

An Ethical Dilemma

Problems with Donating Human Blood

• Short lifespan (RBCs = 3-7 days)

• Antibodies unwanted clotting between blood types– (Type A Type B)

Solution?: Cow Blood

Hemopure:Purified hemoglobin (oxygen carrier)No problems with antibodies

BUT…

It’s Bovine (Cow) – based!Mad Cow Disease!!