7 THE HEART AND BLOOD Flashcards
What is the primary function of the heart?
To beat and pump blood through the body
The heart beats slightly more than once every second, about 100,000 times a day.
How much blood does the heart dispense in an hour?
Around 70 gallons of blood
This amounts to 1,680 gallons in a day.
What are the two phases of a heartbeat called?
Systole and diastole
Systole is when the heart contracts, and diastole is when it relaxes.
What is the difference between systolic and diastolic blood pressure?
Systolic pressure is the highest, diastolic is the lowest
Blood pressure readings are expressed as two numbers, such as 120/80.
What role do valves in the veins play?
Prevent blood from flowing backward
They work alongside muscle contractions in the legs to return blood to the heart.
True or False: Blood pressure is a fixed figure.
False
Blood pressure varies throughout the body and changes throughout the day.
What significant change did the American Heart Association make in 2017 regarding high blood pressure?
Lowered the threshold for hypertension from 140/90 to 130/80
This change resulted in a significant increase in the number of people classified as having high blood pressure.
What is the leading cause of death in the United States?
Heart disease
More than eighty million people suffer from cardiovascular disease.
What distinguishes a heart attack from cardiac arrest?
Heart attack is due to blockage in coronary arteries; cardiac arrest is when the heart stops pumping
Heart attacks can lead to cardiac arrest, but they are not the same condition.
What is bradycardia?
Condition when the heart’s rhythm is too slow
Tachycardia is the opposite condition, where the heart’s rhythm is too fast.
What percentage of blood pumped by the heart goes to the brain?
15 percent
The kidneys receive the greatest amount of blood, at 20 percent.
Fill in the blank: The heart has ______ chambers.
Four chambers
These consist of two atria and two ventricles.
What is the Framingham Heart Study known for?
Identifying major risk factors for heart disease
It began in 1948 and included a diverse group of participants.
What is angor animi?
Anguish of the soul
It refers to a premonition of impending death before a heart failure.
What condition causes sudden deaths among athletes during physical activity?
Hypertrophic cardiomyopathy
It arises from thickening of one of the ventricles.
True or False: Women and men experience heart attacks in the same way.
False
Women are more likely to experience abdominal pain and nausea during a heart attack.
What was the condition of Franklin Delano Roosevelt that raised public awareness of heart disease?
His blood pressure soared to 300/190
His death in 1945 highlighted the severity of heart disease as a public health issue.
What is the average lifespan of a heart in terms of beats?
Approximately 3.5 billion times in a lifetime
This is based on the heart beating slightly more than once every second.
Fill in the blank: The heart weighs less than ______.
A pound
Despite its significant function, the heart is relatively modest in size.
What is the significance of the coronary arteries?
They supply oxygen to the heart muscle
The blood passing through the heart chambers does not nourish the heart itself.
What was the primary purpose of the Framingham study?
To determine the factors that led some people to have heart problems and others to escape them
The study identified major risks for heart disease, including diabetes, smoking, obesity, poor diet, and chronic indolence.
What term is said to have been coined in Framingham?
Risk factor
This term refers to characteristics or conditions that increase the likelihood of developing a disease.
Who was Werner Forssmann?
A young doctor who performed the first catheterization of the heart in 1929
His procedure revolutionized heart surgery despite initially receiving little attention.
What did Forssmann do to prove his catheterization procedure?
He had himself X-rayed to show the catheter in his heart
This act provided visual proof of his groundbreaking work.
What significant medical device did Dr. John H. Gibbon create?
The first heart-lung machine
This invention allowed for open-heart surgery by oxygenating blood artificially.
What technique did Walton Lillehei introduce to improve heart surgery?
Controlled cross-circulation
This technique involved connecting the patient to a temporary donor to circulate blood during surgery.
What was the purpose of a pacemaker?
To regulate a heart that wouldn’t beat correctly
The device helps manage heart arrhythmias.
Who created the first experimental cardiac pacemakers?
Rune Elmqvist and Åke Senning
They developed the pacemakers in Sweden in 1958.
When was the coronary bypass procedure devised, and by whom?
In 1967 by René Favaloro
This procedure involves transplanting a healthy vein to redirect blood flow around a diseased artery.
What was a major obstacle to heart transplantation?
The inability to declare a person dead without stopping the heart
This made it difficult to obtain viable organs for transplant.
Who performed the first successful heart transplant?
Christiaan Barnard
He transplanted a heart in 1967, although the first patient died shortly after the surgery.
What major breakthrough allowed for improved heart transplant success rates in the 1980s?
The development of cyclosporine
This drug helped suppress immune responses, reducing organ rejection.
What percentage of heart transplants are successful by the early 1980s?
80 percent
This marked a significant improvement in transplant outcomes.
What is the average survival time for heart transplant patients?
Fifteen years
This average can vary based on numerous factors, including the patient’s health and the quality of care.
What misconception exists about brain death?
Some peripheral parts of the brain may survive after brain death is declared
This has led to ethical debates regarding the definition of death.
What is a common criticism of elective angioplasties?
They often lack proof of life-saving benefits
Many procedures are performed without clear evidence of their effectiveness.
How much blood does a fully grown man typically have?
About five quarts
The amount of blood varies with body size.
What are the four layers that blood separates into when spun in a centrifuge?
- Red cells
- White cells
- Platelets
- Plasma
Plasma is the most abundant component, constituting over half of blood’s volume.
What is the primary function of plasma?
To transport hormones, nutrients, and waste products
Plasma is crucial for maintaining various bodily functions.
True or False: Heart disease is the leading cause of death in the Western world.
True
Heart disease kills about one in three Americans annually.
What are the four layers blood separates into when spun in a centrifuge?
Red cells, white cells, platelets, plasma
What is the most abundant component of blood?
Plasma
What percentage of plasma is water?
More than 90 percent
What can be separated from plasma and used to treat autoimmune diseases?
Antibodies, clotting factors
What percentage of all goods exported from the United States does plasma sales constitute?
1.6 percent
What are red blood cells formally called?
Erythrocytes
What percentage of blood volume do red blood cells constitute?
About 44 percent
What is the primary function of red blood cells?
Deliver oxygen
How many red blood cells are in a teaspoon of human blood?
About twenty-five billion
What is the shape of red blood cells?
Biconcave
What do red blood cells primarily consist of?
Hemoglobin
What do red blood cells use for their own energy needs?
Glucose
True or False: Hemoglobin prefers oxygen over carbon monoxide.
False
How long does each red blood cell survive?
About four months
What is bilirubin a by-product of?
The breakdown of red blood cells
What is the function of white blood cells?
Fight off infections
What percentage of blood volume do white blood cells constitute?
Less than 1 percent
What are platelets also known as?
Thrombocytes
What percentage of blood volume do platelets account for?
Less than 1 percent
Who first properly understood platelets’ role in clotting?
James Homer Wright
What material do platelets deposit to form a clot?
Fibrin
What happens to blood flow during severe bleeding?
Diverts away from secondary outposts like muscles and surface tissues
What did William Harvey discover about blood circulation?
Blood circulates in a closed system
What misconception did Galen have about blood?
That blood was manufactured continuously in the liver
Who deduced the purpose of blood circulation post-Harvey?
Richard Lower
What was one of the first substances transfused in early transfusion experiments?
Blood from a live sheep
What was George Washington’s treatment that ultimately led to his death?
Bloodletting
What did physicians believe bleeding could do?
Instill calm and relieve ailments
Who was known as the ‘Prince of Bleeders’?
Benjamin Rush
What did Karl Landsteiner discover about blood in 1900?
Blood can clump when mixed from different individuals
What are the three blood groups identified by Landsteiner?
A, B, 0
Who discovered blood types?
Karl Landsteiner
What are the four main blood types identified by Landsteiner and his colleagues?
- A
- B
- AB
- O
What is the significance of blood type O?
Type O blood is known as universal donors.
What role do antigens play in blood typing?
Antigens are proteins that project outward from the cell surface and determine blood types.
What happens when incompatible blood types are mixed?
The recipient’s body attacks the new blood.
Fill in the blank: Blood type A can donate to _______.
A or AB
Fill in the blank: Blood type B can donate to _______.
B or AB
Fill in the blank: Blood type AB can donate only to _______.
AB
What is the Rh factor?
A kind of surface protein called an antigen.
What was the unexpected benefit of blood typing?
Establishing parenthood.
What issue arose in Chicago in 1930 related to blood typing?
Two sets of parents received the wrong babies in a hospital.
What does Dr. Allan Doctor say about blood?
Blood is a living tissue.
How long can blood be stored for transfusion legally in the U.S.?
Forty-two days
True or False: Transfused blood can potentially kill you.
True
What happens to blood after it is taken out of the body?
It begins to degrade.
What was discovered about patients who did not receive transfusions?
They often had better outcomes.
What does nitric oxide do in the body?
It regulates blood flow and acts as a signaling molecule.
What is the primary challenge in creating artificial blood?
Delivering oxygen without losing it.
Fill in the blank: The best approach currently is to reduce the volume of _______.
transfusions
What innovation has Dr. Doctor’s team developed for artificial blood?
A system that keeps hemoglobin inside a polymer shell.
How long can the new artificial blood product be stored?
Up to two years at room temperature.
What major setback occurred in the 1990s regarding artificial blood trials?
Patients had alarming numbers of heart attacks and strokes.
What is the estimated number of people who die each year globally from bleeding?
Up to 2.5 million
What is the problem with transfused blood in relation to the recipient’s existing blood?
It impedes the performance of existing blood.
Fill in the blank: The first human-to-human heart transplant was done by _______.
Dr. Christiaan Barnard
True or False: The term ‘stent’ is named after a dentist.
True
Fill in the blank: The color of our blood is red, but our veins appear _______.
blue
