Exam II Flashcards
(115 cards)
1
Q
What percentage of lean body mass is water?
A
~60%
2
Q
What fraction of TBW is extracellular?
A
1/3
3
Q
What fraction of TBW is intracellular?
A
2/3
4
Q
How many liters of water is TBW?
A
42 liters (for 70 kg person)
5
Q
How is plasma fluid in the interstitial space returned to circulation?
A
Via the lymphatic system
6
Q
What causes edema, in a mechanical sense?`
A
Anything that increases capillary pressure or reduces colloid pressure
7
Q
What kind of edema does right-sided heart failure cause?
A
Systemic edema
8
Q
What kind of edema does left-sided heart failure cause?
A
Pulmonary edema
9
Q
What can cause reduced plasma osmotic (colloid) pressure?
A
Excessive loss or reduced synthesis of albumin
10
Q
What protein is responsible for maintaining osmotic (colloid) pressure?
A
Albumin
11
Q
What can caused reduced synthesis of albumin?
A
Malnutrition or hepatic disease (cirrhosis, hepatic tumors, or hepatitis)
12
Q
Why does nephrotic syndrome reduce colloid pressure?
A
The kidneys become “leaky”, albumin is lost in the filtrate
13
Q
What are the two main causes of lymphatic obstruction, and what does it result in?
A
Inflammatory obstruction or resection of lymphatics, leading to lymphedema
14
Q
What causes peau d’orange?
A
Obstruction of superficial lymphatics by breast cancer tumor (seen in inflammatory breast cancer)
15
Q
What happens in acute renal failure that results in increased water retention?
A
Increased Na+ retention
16
Q
What complication of cerebral edema was discussed?
A
Herniation of brain through foramen magnum, leading to death
17
Q
What percentage of total blood can healthy adults lose acutely?
A
Up to 20%, though more if loss is slow
18
Q
hemorrhage (n.)
A
extravasation of blood due to rupture of blood vessels
19
Q
petechiae (n.)
A
1-2mm hemorrhages in skin/mucous membranes
20
Q
What is usually associated with petechiae?
A
Thrombocytopenia
21
Q
What do you call blood enclosed within tissue?
A
Hematoma
22
Q
purpura (n.)
A
3-5mm hemorrhages in skin/mucous membranes
23
Q
ecchymosis (n.)
A
1-2cm hemorrhages in skin/mucous membranes
24
Q
What differentiates bruises and ecchymoses?
A
Bruises are ecchymoses specifically caused by trauma
25
hemostasis (n.)
the process of causing bleeding to stop (opposite of hemorrhage)
26
What is endothelin?
An endothelial vasoconstrictor
27
What is primary hemostasis?
Platelet aggregation
28
What is secondary hemostasis?
Thrombin recruiting additional platelets
29
How is secondary hemostasis caused?
Tissue factor activates thrombin, which cleaves fibrinogen into fibrin, creating a fibrin mesh network; thrombin also recruits additional platelets
30
What is released to limit coagulation?
Tissue plasminogen activator (t-PA)
31
What does the Virchow Triad define?
The three predisposing factors of thrombosis
32
thrombosis (n.)
the formation of clot inside a blood vessel
33
What are the three components of the Virchow triad?
Endothelial injury, hypercoagulability, and stasis/turbulence
34
What is the dominant factor of the Virchow triad?
Endothelial injury
35
What were the three examples of non-disruptive endothelial injury?
Radiation, hypercholesterolemia, and cigarette smoke
36
What are the three things that stasis/turbulence do to cause thrombosis?
Disrupt the normal laminar blood flow; prevent dilution of activated clotting factors; prevent inflow of clotting factor inhibitors
37
What are five causes of high risk hypercoagulability?
Prolonged bed rest, myocardial infarction, tissue damage, cancer, and inflamed/prosthetic cardiac valves
38
What are five causes of low risk hypercoagulability?
Atrial fibrillation, cardiomyopathy, oral contraceptives, sickle cell anemia, and smoking
39
What is thrombus embolization?
Dislodging some or all of the thrombus to a distant site
40
What is phlebothrombosis?
Formation of a blood clot in venous circulation sans vein inflammation (phlebitis)
41
Where do venous thrombi embolize?
Towards the lungs
42
How are thrombi broken up naturally?
Dissolution by fibrinolytic activity
43
What is the main cause of pulmonary embolization?
Deep vein thrombosis (DVT) in the legs
44
cor pulmonale (n.)
right ventricular failure, or pulmonary heart disease
45
What is the main cause of systemic embolization?
Intracardiac wall thromboses
46
What causes most intracardiac wall thromboses?
Left ventricular infarcts
47
How what percent of systemic emboli occur in the brain?
10%
48
What are the five kinds of emboli?
Thrombus, fat, cholesterol, gas, and amniotic fluid
49
What is a fat embolus usually caused by?
Fracture of a long bone, especially the femur
50
What is a cholesterol embolus usually caused by?
Atherosclerotic debris
51
What causes an amniotic fluid embolism?
A tear in the placenta and rupture of uterine veins
52
What happens to the patient after amniotic fluid embolizes?
Immediate hypotensive shock; if survived, followed by DIC
53
What does DIC stand for?
Disseminated intravascular coagulation
54
What is the immediate cause of DIC?
Widespread fibrin thrombi
55
Is DIC a primary disorder?
No, it is a complication.
56
What is "shock"?
Cardiovascular collapse
57
Describe the cardiovascular collapse seen in shock.
Systemic hypoperfusion as a result of decreased cardiac output or circulating blood volume
58
What are the five main causes of shock?
Severe hemorrhage, extensive trauma/burns, large myocardial infarction, massive pulmonary embolism, and microbial sepsis
59
What are the five types of shock?
Cardiogenic, hypovolemic, anaphylactic, neurogenic, and septic
60
What causes 70% of septic shock deaths?
Gram-negative bacteria
61
What causes gram-negative bacterial sepsis?
Degradation in bacterial cell wall, releasing toxic lipopolysaccharides
62
What is the physiological causes of anaphylactic shock?
General release of histamine, causing hypotension
63
infectious disease (n.)
a disorder in which tissue damage or dysfunction is caused by a microorganism
64
virulent (n.)
capable of causing disease
65
What are the four properties that allow an organism to achieve infection?
Gain access to body; avoid multiple host defenses; accommodate to growth within human body milieu; parasitize human resources
66
What is the virulence of Q-fever?
Inoculum of only one organism needed for infection
67
What are two organisms that can penetrate intact skin?
HPV (genital warts) and T. pallidum (syphilis) can penetrate warm, moist skin
68
What is filariasis?
Obstruction of lymphatics by inflammation and fibrosis of lymphatics, caused by helminths
69
Why do women have UTIs more than men?
Shorter urethra (5-20 cm)
70
What is the organism that causes the plague?
Yersinia pestis
71
What class of organisms cause malaria?
Protozoans
72
What organism causes malaria?
Plasmodium vivax
73
Where does P. vivax attach?
Human RBCs by the Duffy blood group receptors
74
What causes chickenpox?
Varicella-zoster virus
75
What are the three main modes of disease transmission?
Direct contact, indirect contact, and vectors
76
What are the four types of direct contact transmission?
Respiratory aerosol, skin, sexual, and transplacental/vertical
77
What are the five types of indirect contact transmission?
Fomites, blood, stool, water, and soil
78
What is a fomite?
Inanimate object
79
What are the two main transmission vectors?
Arthropods and animals
80
What are four example arthropod vectors, and what diseases are associated?
Mosquito - malaria, yellow fever, dengue fever; Tick - Lyme disease; Louse - typhus, relapsing fever; Mite - scabies
81
What causes cat scratch fever?
Bartonella henselae, a gram-negative organism
82
What are the nine general mechanisms of bacterial pathogenesis?
Produce toxins; produce a slimy, phagocytic-resistant polysaccharide coat; free radical resistant cell wall glycolipids; produce substances that bind opsonins; invade epithelial cells; damage to organs/tissues from inflammatory response; grow in areas that are normally sterile; enter into bloodstream and multiply within tissue; consume host resources
83
What are bacteriophages?
Viruses that infect bacteria
84
What disease is caused by Mycobacterium leprae?
Leprosy
85
What disease is caused by Mycobacterium tuberculosis?
Tuberculosis (TB)
86
What organism multiplies in the normally sterile lung and causes pneumococcal pneumonia?
Streptococcus pneumoniae
87
What are two diseases caused by bacteriophages?
Diphtheria (Corynebacterium diphtheriae) and cholera (Vibrio cholerae)
88
plasmid (n.)
an extrachromosomal genetic element not necessary for genetic growth
89
What are three Clostridium species that secrete exotoxins?
C. perfringens, C. tetani, and C. botulinum
90
What are the three representative Gram-positive infections we discuss?
Staphylococcus aureus, Streptococcal infections, and Corynebacterium diphtheriae
91
What is the shape of C. diphtheriae, and how is it passed?
Gram-positive rod, passed by aerosols
92
What is diphtheria?
A tough pharyngeal membrane that can block the pharynx, and is toxic to the heart and nerves
93
What organism is one of the leading causes of bacterial pneumonia and meningitis?
Streptococcal pneumoniae
94
endocarditis (n.)
infection of the inner lining of the heart and heart valves
95
What is the organism and pathogenesis of tetanus?
C. tetani - secretes an exotoxin that interferes with inhibitory neurotransmitters (ie. GABA), causing violent muscle spasms
96
What is the organism and pathogenesis of botulism?
C. botulinum - secretes an exotoxin that blocks the release of ACh, causing paralysis
97
What is the general treatment for gram-positive infections?
Sensitive to penicillins, erythromycins, & cephalosporins
98
What disease does Rickettsia prowazekii cause?
Typhus
99
What disease does Rickettsia rickettsii cause?
Rocky Mountain spotted fever
100
Why are Rickettsia bacterias considered obligate intracellular parasites?
Cannot utilize glucose as an energy source; may need NAD+ and coenzyme A
101
Why are Chlamydiae bacterias considered obligate intracellular parasites?
They cannot make ATP
102
When and where was the last case of smallpox?
Somalia, 1977.
103
What are the symptoms and signs of smallpox?
Sudden onset of high fever, chills, headache, lumbar back pain, and prostration, with common nausea and vomiting; after 2-4 days, rash appears on face, extremities, trunk, and mucous membranes of mouth/eye, progressing over 2-4 weeks
104
What was tuberculosis called in the 18th century?
Consumption
105
How much of the world's population is infected with TB?
1/3 of world pop.
106
What are the early symptoms of tuberculosis?
Fever, night sweats, weight loss, anorexia, and weakness
107
What is the prognosis of those with untreated TB?
1/3 die within one year; 1/2 die within five years
108
What is the cause of death in tuberculosis?
Respiratory compromise, cachexia, or other organ involvement
109
cachexia (n.)
malnutrition induced by chronic disease
110
What organism causes most human cases of TB?
Mycobacterium tuberculosis
111
What is the shape of M. tuberculosis?
Slender, rod-shaped bacteria
112
How does someone become infected with tuberculosis?
Inhalation of the "tubercle bacilli" (bacteria)
113
What organism causes anthrax?
Bacillus anthracis
114
What are the three forms of anthrax, and what is the relative incidence of each in the US?
Cutaneous (95%), inhalational (5%), and gastrointestinal (only 11 cases reported)
115
What is the mortality rate of inhalational anthrax?
95-100% if untreated; death within 24 hours
