Patho - Term Test I Flashcards

(318 cards)

1
Q

How much body weight is water?

A

60% of total body weight

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2
Q

What are the two components of body fluids?

A

ICF (2/3 of TBW) and ECF (1/3 of TBW)

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3
Q

What consistitutes ECF (i.e. what are the components of ECF)

A

blood plasma (intravascular fluid), interstitial fluid, transcellular fluids (CSF, synovial fluid)

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4
Q

What is intersitital fluid?

A

Fluid that is found in spaces between cells but not within blood vessels

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5
Q

When is anaerobic glycolysis used?

A

When there is no oxygen present, cells use this method to breakdown glucose (pyruvate and lactic acid as byproducts)

  • not a very efficient process (makes little ATP)
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6
Q

Define intravascular fluid

A

fluid found within blood vessels (aka blood plasma)

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7
Q

Define transcellular fluid and provide an example.

A

Fluid contained within epithelial-lined cavities of the body (smallest component of ECF)

ex. CSF, synovial fluid, urine, GI fluids, pleural fluids, pericardial fluids, peritonial fluids)

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8
Q

What are two methods in which you would inevitably lose fluids?

A

sweat and lung ventilation

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9
Q

Rank from greatest to least: water loss from these following methods

1) ventilation
2) stool
3) perspiration
4) renal excretion

A

renal > ventilation > perspiration > stool

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10
Q

What are the major cations and anions in ECF?

A

sodium (Na+)

chloride (Cl-)

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11
Q

What are the major cations and anions in ICF?

A

K+, phosphates and Mg2+

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12
Q

What forces move water between ICF and ECF

A

osmotic forces

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13
Q

Define Starling Forces. What are the 4 forces?

A

Forces that determine whether net effect is filtration or reabsorption

1) capillary hydrostatic pressure
2) capillary oncotic pressure
3) interstitial hydrostatic pressure
4) interstitial oncotic pressure

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14
Q

What does capillary hydrostatic pressure do?

A

facilitates water movement from capillary to interstitial space

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15
Q

What does capillary oncotic pressure do?

A

osmotically attracts water from interstitial spaces to capillary

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16
Q

What does interstitial oncotic pressure do?

A

osmotically attracts water from capillary to interstitial spaces

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17
Q

What does interstitial hydrostatic pressure do?

A

facilitates water movement from interstitial space to capillary

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18
Q

Which of the 4 starling forces promote fluid and proteins into lymphatics

A

interstitial hydrostatic pressure

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19
Q

True or false: Water, sodium and glucose move readily across capillary membrane

A

TRUE

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20
Q

True of False: albumin and other proteins move across capillary membrane to facilitate hydrostatic/oncotic pressures

A

False. They do not cross the membrane. Proteins stay in the capillary and generate oncotic pressures within plasma

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21
Q

Define filtration

A

movement of fluid out of capillaries and into interstitial space

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22
Q

Define reabsorption

A

fluid movement into capillaries from intersitial space

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23
Q

At the arterial end of capillary, is hydrostatic or oncotic pressure higher?

A

hydrostatic

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24
Q

At venous end of capillary, is hydrostatic or oncotic pressure higher?

A

oncotic

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25
True or False: Typically intracellular and extracellular fluid osmotic pressures are equal, and water is equally distributed between interstitial and intracellular components
True
26
Which cation is responsible for osmotic balance of ECF?
Na+
27
Which cation is responsible for osmotic balance of ICF?
K+
28
What is edema?
excessive accumulation of fluid within interstitial spaces (fluid shifts from capillaries or lymphatic vessels --> interstitial spaces
29
What are the 4 causes of edema?
1) increased capillary hydrostatic pressure 2) decreased plasma oncotic pressure 3) increased capillary membrane permeability 4) lymphatic channel obstruction
30
How does increased capillary hydrostatic pressure cause edema? provide 2 explanations
1) venous obstruction (increased hydrostatic pressure behind the obstruction and fluid is pushed into interstitial spaces) 2) salt/water retention - causes volume overload leading to increased capillary hydrostatic pressure and edema
31
Provide two conditions that causes edema due to increased capillary hydrostatic pressure secondary to venous obstruction.
Any two: - thrombophlebitis - hepatic obstruction - tight clothing around extremities - prolonged standing
32
Provide a condition that causes edema due to increased capillary hydrostatic pressure secondary to salt/water retention
CHF, renal failure, liver cirrhosis
33
How does decreased plasma oncotic pressure cause edema?
due to decreased or loss of protein production (albumin) that typically holds onto water in blood vessels (so fluid remains in interstitial spaces)
34
Provide two conditions that causes edema due to decreased plasma oncotic pressure.
Any of these: - protein malnutrition - liver disease (reduced albumin production) - glomerular diseases of the kidney - serous damage from open wounds - hemorrhage - burns - liver cirrhosis
35
How does increased capillary membrane permeability lead to edema?
proteins escape from within blood and into interstitial spaces which decreases capillary oncotic pressure so fluids are not pulled back into capillaries and protein buildup in interstitial fluid - typical in inflammatory responses
36
Provide two conditions that cause edema due to increased capillary membrane permeability
- trauma (burns/crush injuries) - allergic reactions - neoplastic diseases (conditions that cause abnormal cell growth)
37
How does lymphatic channel obstruction lead to edema?
``` if the channels are blocked it will lead to protein and fluid accumulation within interstitial space (cannot be drained) aka lymphedema (firm and non-compressible) ```
38
Provide two conditions that cause edema due to lymphatic channel obstruction.
any of the following: - surgical removal of lymph nodes in arm/leg - radiation therapy (can cause scar tissue formation that presses on the lymphatic channels) - obstruction from malignant tumours - infection
39
True or false: fluid accumulation does not affect nutrients and waste travelling through the capillaries and tissues
False. fluid accumulation increases distance they have to travel
40
Define pitting edema
When an indentation (pit) is left on the skin after being pressed
41
Define effusion
fluid accumulation within a body cavity or space
42
Severe generalized edema is also known as
anasarca
43
Dependent edema occurs when ______
fluid accumulates in gravity-dependent areas of the body (ex. legs and feet when standing)
44
How do you treat edema? Provide at least two interventions.
- diuretics - elevation of swollen limbs - compression stockings - restricting salt intake - IV albumin for severe cases
45
What systems regulate sodium, chloride, and water?
renal and endocrine systems
46
Sodium balance is regulated by _________ and ________; water balance is regulated by ___________
aldosterone, renal tubular reabsroption within kidney ; ADH
47
What three factors influence aldosterone secretion?
1) circulating blood volume 2) BP 3) plasma concentration of Na+ and K+
48
Describe how the renin-angiotensin-aldosterone system (RAAS) works when there is a decrease in blood pressure.
1) Decrease in blood volume or pressure causes renin to be secreted from juxtaglomerular cells in kidney 2) renin stimulates formation of angiotensin I 3) Angiotensin I converted to Angiotensin II by ACE 4) Angiotensin II is a vasoconstrictor so it increases BP by constricting blood vessels and renal perfusion is restored 5) Angiotensin II also stimulates aldosterone and ADH release to Na+ and water reabsorption, and K+ excretion --> blood volume increased
49
What are natriuretic peptides?
Hormones primarily produced by myocardium, natural antagonists of RAAS
50
What is the function of natriuretic peptides?
When increase BP is detected, natriuretic peptides cause vasodliation and increase Na+ and water secretion to decrease BP ex. in CHF
51
True or false: changes in chloride concentration are proportionate to changes in sodium concentration
True
52
How does ADH (vasopressin) regulate water balance when plasma osmolality increases?
1) Increased plasma osmolality and circulating blood volume decreases (drop in BP) stimulate hypothalamus osmoreceptors that induce thirst sensation and ADH release 2) Increased fluid intake and water reabsorption in the distal tubules occurs 3) TBW increases 4) plasma osmolality decreases to normal
53
What are three common causes of dehydration?
excessive sweating, vomiting, inadequate intake
54
Where are volume-sensitive receptors found?
right and left atria; thoracic vessels
55
Where are baroreceptors found?
Aorta; pulmonary arteries, carotid sinus
56
Define isotonic fluid alterations
Changes in total body water with PROPORTIONAL changes of electrolytes
57
isotonic fluid loss causes (hypervolemia/hypovolemia)
hypovolemia
58
Four common causes of hypovolemia?
- hemorrhage - severe wound drainage - excessive sweating - inadequate fluid intake
59
Which of the following is not a symptom of hypovolemia? 1) flat neck veins 2) increased HR, decreased BP 3) weight loss 4) increased urine output 5) dry skin and mucous membranes
increased urine output (output would actually decrease in hypovolemia)
60
What is the general treatment for hypovolemia?
Fluid replacement with isotonic solutions - 0.9% normal saline - 5% dextrose (D5NS) - Ringer's Lactate - Pediatric oral replacement solution - sports beverages
61
Isotonic fluid excess causes (hypervolemia/hypovolemia) as well as weight (gain/loss) and (increased/decreased) hematocrit and plasma protein concentration.
hypervolemia; gain; decreased
62
Common causes of hypervolemia?
- excess administration of IV fluids - hypersecretion of aldosterone - effect of drugs (i.e. cortisone)
63
Which of the following is a sign/symptom of hypervolemia? 1) neck vein distension 2) increased BP 3) edema 4) development of pulmonary edema and heart failure 5) all of the above
all of the above
64
Treatment for isotonic fluid excess (hypervolemia) includes:
diuretics
65
Define isovolemic hypernatremia.
When there is a deficit of free water accompanied by normal/near normal body sodium concentration *the most common presentation of hypernatremia
66
Common causes of isovolemic hypernatremia:
``` inadequate water intake vomiting diarrhea excessive sweating burns resp. tract infections and fever (increased breathing leading to water loss) ``` *less common: diabetes insipidus (due to lack of ADH or inadequate response to ADH)
67
Define hypovolemic hypernatremia
When there is a loss of Na+ accompanied by a greater loss of water
68
Provide an example of a common cause of hypovolemic hypernatremia.
Any of the following: - loop diuretics (increase water loss but inhibit sodium reabsorption) - renal failure (can't concentrate urine so loss of large volumes) - diabetes-induced hyperglycemia (excess urinary solute that is non-reabsorable so water goes with it) - osmotic diuretics (impairs renal concentrating capacity, ex. mannitol)
69
Define hypervolemic hypernatremia
When there is an increase in TBW with an even greater increase in Na+ level
70
All of the following cause hypervolemic hypernatremia except: 1) oversecretion of aldosterone or adrenoorticotropic hormone (ACTH) 2) vomiting 3) infusion of hypertonic saline solution in cases of salt depletion 4) Cushing syndrome 5) all of them cause hypervolemic hypernatremai
2) vomiting (does not cause hypervolemic hypernatremia)
71
Describe isovolemic hyponatremia
loss of Na+ without significant loss of water (purely just missing Na+)
72
Provide an example of a common cause of isovolemic hyponatremia.
- hypothyroidism - pneumonia - glucocorticoid deficiency (due to impaired renal free water clearance = diluted [Na+]) - water retention secondary to inappropriate ADH (SIADH) - in those who are on low sodium diets + take diuretics
73
Treatment for isovolemic hyponatremia
vaptans (ADH receptor antagonists)
74
Describe hypovolemic hyponatremia
occurs when there is a loss of TBW but an even greater loss of Na+
75
Which of the following is not a common cause of hypovolemic hyponatremia? 1) prolonged vomiting 2) renal losses from diuretics 3) severe diarrhea 4) excess IV fluid administration 5) adrenal insufficiency (inadequate secretion of aldosterone)
excess IV fluid administration
76
Describe hypervolemic hyponatremia
An increase in Na+ levels but and even greater increase in TBW (dilution of Na+)
77
Provide a condition that causes hypervolemic hyponatremia
*think fluid overload* - edema usually occurs - CHF - liver cirrhosis - nephrotic syndrome
78
Treatment for hypervolemic hyponatremia includes:
vaptans (ADH receptor antagonists)
79
Describe dilutional hyponatremia
- aka water intoxication when large amounts of free water are taken in or if IV fluids (without salt so like dextrose in water) is given causing dilution in sodium
80
Which of the following is a common causes of dilutional hyponatremia? 1) tap water enemas 2) endurance sports (drinking lots of water, no eletrolytes) 3) compulsive water drinking 4) near drowning in fresh water 5) use of SSRIs 6) all of the above
all of the above
81
Treatment for dilutional hyponatremia includes
water restriction
82
True or false: hypokalemia is prevalent in elderly, those with alcoholism, and anorexia nervosa
True
83
Treatment of hypokalemia includes what?
Eaching potassium rich foods, replacement therapy to replace lost K+ and then treating underlying mechanism
84
Common causes of hyperkalemia include:
- increased intake of K+ - trauma to cell that causes shift of K+ from ICF to ECF - decreased renal excretion/compromised renal function - drugs that decrease renal K+ excretion (ACE inhibitors, angiotensin receptor blockers, aldosterone antagonists) - burns & crush injuries (in response to severe burn/injuries, extra K+ is released in the blood) - extensive surgeries (cells release extra K+ or from blood transfusions) - insulin deficit (cannot faciliate uptake of K+ into cells) - Digitalis toxicity (blocks Na-K ATPase pump so K+ can't go into cells)
85
Treatment for hyperkalemia includes which of the following: 1) calcium gluconate (for cardiac membrane potential) 2) glucose administration 3) administration of K-binding agents 4) dialysis 5) all of the above
all of the above - calcium gluconate helps stabilize cardiac membrane potential and therefore restores neuromuscular irritability) - Glucose administration: stimulates insulin secretion to facilitate K+ uptake into cells - administration of K-binding agents (and lower K+ levels) - dialysis to remove excess K+ in cases of renal failure
86
Causes for hypophosphatemia
- malabsorption syndromes (long term alcohol use, vitamin D deficiency, use of Mg or aluminum containing antacids) - respiratory alkalosis (increased pH causes increased cellular demands for phsophate so a fall in levels extracellularly) - increased renal excretion of phosphate (associated with hyperparathyroidism)
87
Causes for hyperphosphatemia
- hypoparathyroidism (cannot inhibit phosphate reabsorption in the kidney) - acute/chronic renal failure (cannot filter it out) - treatment of metastatic tumours (chemotherapy because it releases large amounts of phosphate into serum) - long term use of laxatives and enemas with phosphates
88
Which of the following are potential causes of hypomagnesemia? 1) malnutrition 2) malabsorption syndromes 3) alcoholism 4) urinary losses (loop diuretics, renal tubular dysfunction) 5) 1 and 3 6) all of the above
all of the above
89
Provide an example of a cause for hypermagnesemia.
- renal failure or insufficiency - excessive intake of Mg-containing antacids - adrenal insufficiency
90
What are volatile acids?
substances that can be eliminated through CO2 through lungs (ex. carbonic acid)
91
What are non-volatile acids?
substances that can be eliminated only by kidneys
92
Does the respiratory rate go up or down during acidosis?
up - trying to breathe off CO2
93
What is the definition of pathophysiology?
Study of underlying changes in body physiology resulting from disease or injury
94
What leads to metabolic acidosis?
increase in acid concentration or lost of bicarbonate in ECF (ratio is less than 20:1)
95
How does the body compensate in metabolic acidosis?
hyperventilate (Kussmaul's respirations) and excrete H+
96
What leads to metabolic alkalosis
elevated HCO3- usually caused by excessive loss of metabolic acids (from vomiting or diuretics where you're losing a bunch of ions specifically Cl-)
97
How does the body compensate for metabolic alkalosis
- suppress breathing | - kidneys try to excrete excess HCO3-
98
What leads to respiratory acidosis?
increased partial pressure of CO2 (hypercapnia) resulting from hypoventilation
99
How does the body compensate for respiratory acidosis
increase breathing to blow off CO2 and renal compensation by eliminating H+ and retention of HCO3-
100
What leads to respiratory alkalosis?
hyperventilation causes decrease in partial pressure of CO2 (co2 in blood)
101
How does the body compensate for respiratory alkalosis?
Slow down breathing, kidneys compensate by decreasing H+ excretion and bicarbonate reabsorption
102
True or False: Newborns are more susceptible to changes in TBW due to high metabolic rate and greater surface area
True
103
True or false: adaptation is a reversible response involving structural or functional modifications to accommodate both physiologic (normal) and pathologic (adverse) demands/conditions
true
104
sublethal cellular injuries are (reversible/irreversible) while lethal cellular injuries are (reversible/irreversible)
reversible; irreversible
105
What are the 8 common sources of cell injuries?
1) ischemic-hypoxic 2) ischemia 3) free radicals 4) reperfusion 5) immunologic 6) infectious 7) intentional/unintentional 8) inflammatory
106
What are the two main cell death types?
necrosis, apoptosis (and a third process - autophagy but not really cell death type)
107
Atrophy
shrinking in cell size
108
Common organs that are affected by atrophy?
heart, skeletal muscle, secondary sex organs, brain
109
Hypertrophy
increase in cell size (in response to mechanical load/stress)
110
Hypertrophy is common in which organs?
heart, kidney
111
Hyperplasia
increase in cell number (resulting from increased rate of cellular division, growth factors or increased output of new cells from tissue stem cells)
112
Metaplasia
reversible replacement of one mature cell type (epithelial or mesenchymal) by another cell type, frequently one less differentiated.
113
Lung cells being replaced in a long term smoker to cells that do not secrete mucus/have cilia is an example of what type of cellular adaptation?
Metaplasia
114
Dysplasia
- aka atypical hyperplasia - abnormal/deranged cellular growth (changes in size, shape, and organization of mature cells) - can be described as high grade or low grade - Dysplasias that do not involve the entire thickness of epithelium may be completely reversible
115
Where is dysplasia commonly found?
in epithelial tissue of: uterine cervix, endometrium, GI and respiratory tract mucosa, also often found next to cancer cells (not indicative of cancer though)
116
When does cellular injury occur?
When cell is unable to maintain homeostasis
117
Which of the following in not a general mechanism of cellular injury? 1) ATP depletion 2) increased ROS 3) Ca2+ entry 4) mitochondrial/membrane damage 5) K+ entry 6) protein misfolding
K+ entry
118
How does reperfusion cause cellular injury?
1) increases oxidative stress (damages membrane and Ca+2 buildup) 2) calcium buildup (from damaged cell membrane + ROS-mediated injury lead to enhanced mito permeability leading to minimal to no ATP production) 3) inflammation (dead cells stimulate immune cells) 4) complement activation (exacerbates damage)
119
What is oxidative stress?
When there is a buildup of reactive oxygen species that exceeds antioxidant's ability to detoxify
120
How does free radicals cause cellular injury?
the unpaired electrons are unstable so they try to stabilize self by forming bonds with proteins, lipids, and carbs and change a bunch of shit in the cells leads to: - lipid peroxidation (destroying lipids = damage to membrane) - protein alterations - DNA damage (mutations) - mitochondrial dysfunction
121
What are xenobiotics?
compounds that have toxic, carcinogenic, or mutagenic properties that are found in an organism but not naturally produced within said organism
122
Signs and symptoms of lead poisoning include what? Treatment?
- GI symptoms (abdominal cramping, nausea, loss of appetite, weight loss) - glucose, amino acids, and phosphates in urine Treatment: - removal of exposure source, chelation therapy (removes heavy metals from the body), correcting mineral deficiencies in the body
123
Lead poisoning in children can cause:
- cognitive deficits - behavioural changes (antisocial behaviour, attention deficits) - hyperpigmentation in gums * children are most susceptible due to increased hand-mouth behaviour, blood brain barrier not mature yet, and infants absorb lead more than adults do - also lead paint chips off the wall have sweet taste
124
Signs and symptoms of CO poisoning include:
tinnitus, nausea, vomiting, weakness, dizziness
125
Signs of FASD
``` microcephaly low birth weight cardiovascular defects growth retardation facial anomalies cognitive impairment ocular malformations ```
126
What substance causes the colour of periorbital ecchymosis?
hemosiderin
127
Mercury poisoning can negatively impact:
fetal brain development (if exposed during pregnancy)
128
How can mercury affect large groups of people?
climate change and thawing of frozen lands can release long stored mercury into bodies of water
129
True or false: Ethanol can lead to nutritional deficiencies
True
130
How does ethanol affect folic acid in the body?
1) decreased intestional absorption of folate 2) increased liver retention of folate 3) increased loss of folate through urine and feces
131
Describe blunt force injuries
Mechanical injury that results in tearing, shearing or crushing (blows, impacts, MVAs, falls)
132
What are contusions?
bleeding into skin or underlying tissues (aka bruises)
133
What is the typical trajectory of colour for contusions?
red-purple => blue-black => yellow-brown or green
134
Lacerations
tear/rip resulting when tensile strength of skin/tissue is surpassed (irregular abraded edges)
135
Avulsions
wide area of tissue pulled away
136
Incised wound
A wound that is longer than deep - more external bleeding than internal
137
Stab wound
A wound that is deeper than long - more internal bleeding, external bleeding may be small and wound may be closed by tissue pressure
138
Puncture wound
wound by sharp points but not sharp edges - prone to infection, can be deep
139
Chopping wound
heavy, edged instruments producing wounds that are a combination of sharp and blunt force injuries
140
Penetrating vs perforating GSW
Penetrating: bullet remains in body Perforating: bullet exits body * bullets can also fragment
141
What are the two most important factors when considering GSW and the severity of injury?
whether there is an entrance/exit wound and range of fire
142
Contact entrance wound
gun is held so muzzle sits on skin - obvious burn marks
143
Intermediate distance range entrance wound
usually gunpowder tattooing or stippling due to abrasion of skin from gun powder striking skin when it comes out of the barrel
144
indeterminate range entrance wound
when soot, gunpowder, etc. does not reach skin surface but bullet does (appearance is the same regardless of distance)
145
True or false: exit wound has the same appearance regardless of range of fire
true *usually has clean edges and can reapproximate to cover defect
146
Wound potential of bullets depend on what?
depends on energy transferred to tissue impacted (Speed has much greater effect than size)
147
What are the four categories of asphyxial injuries?
Suffocation (choking asphyxiants) strangulation (hanging, ligature, manual strangulation) chemical asphyxiants (cyanide, hydrogen sulfide) drownings
148
Suffocation
process of dying as a result of lack of oxygen (lack of O2 in the environment such as methane, or blockage of respiratory airways)
149
When does choking asphyxiation occur?
when there is an obstruction of pulmonary airways (i.e. lodged object or airway swelling)
150
What are the two main signs that indicate choking asphxyiation?
petechiae (small capillaries breaking leading to red points on skin - due to obstruction of blood flow back to heart), florid facial congestion
151
Strangulation is caused by
compression of blood vessels and air passages resulting from external pressure on the neck
152
True or false: in strangulation, people typically die due to lack of airflow
False - it's due to no blood flow to the brain
153
Hanging strangulation vs. ligature strangulation
Hanging strangulation - inverted V shape ligature mark, patient has severe soft tissue injury and c-spine trauma (petechiae in eyes/face) Ligature strangulation - no suspension, some form of cord tightens around neck (petechiae common due to intermittent releasing of ligature during struggle)
154
Manual strangulation is defined as
use of hands to compress neck of victim to point where death by asphyxiation occurs - usually noted with external neck trauma and internal damage (bruising to deep structures, fractures), petechiae
155
How do chemical asphyxiants cause asphyxiation?
they prevent deliver of O2 to tissues or block O2 use
156
Provde 4 examples of chemical asphyxiants
methane, CO, hydrogen sulfide, cyanide
157
cyanide poisoning has what presentation?
cherry red colouration to skin and mucus membrane; smells like almonds
158
Patients who have suffered from hydrogen sulfide (sewer gas) asphyxiation will present with what?
- brown tinged blood - signs of asphyxiation - rotten egg smell
159
True or False: Methane displaces oxygen, causes asphyxiation
True
160
Define: drowning
lack of oxygen delivery from inhalation and suffocation by a liquid (hypoxemia)
161
What is dry lung drowning?
when little to no water enter the lungs during drowning (due to airway being closed off) - caused by vagal nerve mediated laryngospasms that close off airway
162
The virulence of a microorganism is determined by what two factors?
It's ability to SURVIVE and PROLIFERATE in the human body
163
Disease-producing potential of microorganisms depends on what three things?
1) ability to invade and destroy cells 2) produce toxins 3) produce damaging hypersensitivity reactions
164
Inflammatory or immunologic injuries to the cell cause cell membrane alterations. True or False
True - leak K+ out of cell - influx of water - antibodies bind with receptors and interfere with its function - antibodies block cellular junctions (cells can't communicate)
165
Define extravasation
leakage of fluid out of its normal region into surrounding areas where it doesn't belong
166
True or False: Accumulation in calcium salts is a sign of physiologic or pathologic change
False. Cellular calcification only occurs in pathologic changes because it only ever occurs in injured or dead cells (not normal processes therefore not physiologic)
167
Disturbances in urate metabolism lead to what?
Gout
168
Systemic manifestations of cellular injury include all of the following but: 1) fever 2) pain 3) increased HR 4) presence of cellular enzymes 5) leukopenia 6) all of the above are correct
leukopenia The following are systemic manifestations of cellular injury: - fever (endogenous pyrogens) - increased HR (increased oxidating metabolic processes resulting from fever) - pain (from obstruction, pressure, bradykinin) - cellular enzymes (released into ECF) - leukocytosis (bc infection)
169
Define necrosis
Death of cells characterized by rapid loss of plasma membrane structure, organelle swelling and dysfunction, and lacking of typical features of apoptosis
170
Apoptosis
programmed cell death (orderly dismantling of cell contents and packaging remainders in vesicles)
171
What are the 4 major types of necrosis
Coagulative Liquefactive Caseous Fatty
172
Gangrenous Necrosis
not type of necrosis but refers to large areas of tissue death
173
Coagulative necrosis
Area of cell death in which protein denaturation turns proteins into firm and opaque (from gelatinous transparent state)
174
Infarct
area of coagulative necrosis
175
Coagulative necrosis often found in which organs?
kidney, heart, adrenal glands
176
Liquefactive necrosis
When cells are digested by their own hydrolases causing tissue to be soft and runny; cyst formation also occurs
177
Where is liquefactive necrosis commonly found?
In dead brain cells (due to ischemic injuries to neurons and glial cells) AND brain cells are rich in digestive enzymes and lipids
178
Liquefactive necrosis is usually cause by what?
Bacterial infection (e. coli, strep, staph)
179
Caseous necrosis
Area of cell death where dead cells disintegrate but debris not completely hydrolyzed (combo of liquefactive and coagulative necrosis)
180
Caseous necrosis is commonly caused by
pulmonary TB or infection caused by TB
181
What does caseous necrotic tissue look like?
soft, granular tissue (looks like clumped cheese) also often granuloma formation
182
Fatty necrosis
area of cell death where cellular dissolution is caused by lipases releasing fatty acids
183
What does fatty necrotic tissue look like?
Chalk white and opaque
184
Saponification happens in what type of necrosis?
Fatty necrosis (fatty acids combine with Ca, Mg, and Na ions creating soaps)
185
What is the typical cause of gangrenous necrosis?
hypoxia + bacterial invasion
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Dry gangrene vs. wet gangrene
Dry gangrene: result from coagulative necrosis --> dry and shrinking skin, colour is dark brown-black (ex. of cause: diabetes and poor circulation) Wet gangrene: develops when neutrophils invade site causing liquefactive necrosis
187
What does tissue look like in wet gangrene?
tissue becomes cold, swollen, black, foul odor, and death
188
What is gas gangrene?
type of wet gangrene caused by infection of injured tissue by Clostridium (anaerobic bacteria destroys cell membrane and causes gas bubbles to form leading to rapid infection/sepsis, renal shutdown, and potential death
189
When would apoptosis occur pathologically? (4)
from: 1) severe cell injury - can't be revived sorry 2) accumulation of misfolded proteins 3) infections (host says let's destroy cell bc virus is here) 4) obstruction in tissue ducts - blood cannot flow to an organ
190
What are the enzymes that trigger protein breakdown and subsequently apoptosis?
caspases
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What is autophagy?
Eating of self
192
When would autophagy occur?
when cells are starved or don't have nutrients (so digest the cells and recycle contents for better use)
193
True or false: autophagy declines and becomes less efficient as cells age
True - contributes to aging process
194
Aging
Normal physiologic processes that are universal and inevitable (gradual loss of homeostatic mechanisms)
195
True or False: Aging is considered a disease.
No, it's a natural normal process so this is false
196
Life span vs. life expectancy
Life span - period from birth to death | Life expectancy - avg number of years of life remaining at a given age
197
Sarcopenia
loss of muscle mass and strength as we age
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True or False: Cells, tissues, and body systems age and extracellular changes all occur as we get older
True
199
Frailty is characterized by: (3 things)
overall weakness, decreased stamina, and functional decline
200
Somatic death
Death of the entire body
201
Postmortem changes
changes that occur after death
202
Pallor mortis
1st stage - skin becomes pale and yellowish
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Algor mortis
2nd stage - body temperature drops because heart is not pumping (usually falls to temp of the environment)
204
Rigor mortis
3rd stage - stiffening of muscles (within 6 hours of death) - happens due acidic compounds accumulating within muscles from to contractile proteins failing leading to muscle rigidity - smaller muscles usually affected first (like the jaw)
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Livor mortis
4th stage - gravity causes blood to settle in most dependent/lowest tissues developing purple discolouration
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Postmortem autolysis (aka putrefaction)
Tissues and organs lose cohesiveness as they breakdown into gaseous and liquid matter (24-48 post death)
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Signs of putrefaction include:
- greenish discolouration of skin (eventually turns black) - swelling and bloating due to gas build up - organs begin to liquefy - rate depends on environmental temp
208
Atrophy of the thymus gland is classifised as what type of atrophy?
physiological (i.e. occurs with early development, normal)
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Atrophy in a limb after being placed in a cast is known as:
disuse atrophy
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Pathologic atrophy occurs when?
decreases in workload, pressure, use, blood supply, nutrition, and hormonal/neuronal stimulation - disuse atrophy would also fall under this category
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Physiological vs pathologic hypertrophy
Physiologic: from increased demand, stimulation by hormones, and growth factors Pathologic: chronic hemodynamic overload (hypertension) leading to contractile dysfunction and then heart failure
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True or false: cellular adaptations usually only work short term and cannot withhold long term stressors
True (long term stressors will overwhelm adaptive process leading to cell injury/death)
213
There are two types of physiological hyperplasia. What are they and give an example of each.
Compensatory hyperplasia: enables organs to regenerate (i.e. liver, calluses, wound healing secondary to inflammation process) Hormonal hyperplasia: occurs in organs that respond to endocrine hormonal stimulation (follicular phase of menstrual cycle where estrogen secretion causes endometrial proliferation)
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What is pathologic hormonal hyperplasia? Provide 3 examples.
abnormal proliferation of normal cells usually in response to excessive hormone stimulation or growth factors ex. BPH - benign prostate hyperplasia - thyroid goiters - pathology hyperplasia of the uterine endometrium
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S/Sx of pathologic hyperplasia of uterine endometrium include:
erratic/excessive bleeding (aka dysfunctional uterine bleeding) - due to imablance between estrogen and progesterone levels - may lead to malignancy and endometrial cancer if not treated
216
List the steps in which cellular injury leads to hydropic degeneration.
1) injury leads to hypoxia 2) ATP production decreases 3) Na+ and H2O moves into cell, K+ moves out of cell 4) osmotic pressure increases 5) more water moves into cell 6) cisternae of ER distend, rupture and form vacuoles 7) extensive vacuolation 8) hydropic degeneration
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What is the single most common cause of cellulary injury?
ischemia and hypoxic injury (and ischemia is the most common cause of hypoxia)
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Ischemia and hypoxic injury results from what causes?
- reduced amount of O2 in the air - loss of Hb or decreased efficacy of Hb - Decreased RBC production - Resp. or CV diseases (arteriosclerosis) - Poisoning of oxidative enzymes (cytochromes) within cells
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Define vacuolation
formation of vacuoles aka storage bubbles found in cells (within cytoplasm)
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What processes are happening during ischemic and hypoxic injury?
Blood supply interrupted leading to heart dysfunction and unable to contract normally - within 3-5 minutes, mitochondria doens't function properly --> insufficient ATP production --> heart can't contract because of lack of ATP --> anaerobic metabolism until glycogen stores are depleted --> Na-K pumps now cannot work because they need ATP to function --> Na+ and Ca+2 go into cell while K+ diffuses out --> K+ swells --> vacuolation
221
Reperfusion injury and reactive oxygen readicals ultimately lead to ______.
necrosis
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What is ROS (reactive oxygen species)?
reactive molecules from molecular oxygen formed as a natural oxidant species in cells during mitochondrial respiration and energy generation --> cause oxidative stress
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What sources/causes lead to free radical formation?
- redox reactions - absoprtion of extreme energy sources (UV, radiation) - metabolism of exogenous chemicals/drugs (substances in the environment like CCl3) - transition metals (iron, copper) - nitric oxide
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Biotransformation
a process whereby enzymatic reactions convert one chemical into a less toxic or nontoxic compound (happens a lot in the liver when chemicals/drug enter the body)
225
What are antioxidants?
molecules that inhibit oxidation of other molecules to prevent formation of free radicals
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The leading cause of poisoning in children is what?
medications (including inappropriate administration of over the counter preparations of acetaminophen)
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The most common site for chemically induced injury is:
liver
228
The single largest environment health risk is
air pollution
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True or false. Lead (Pb) in the body leads to increased oxidative stress and is found commonly in older homes, workplaces, and in the environment
True
230
Symptoms of arsenic poisoning include:
Acute GI, CV, and CNS toxicities (often fatal) - chronic exposure could lead to skin lesions (hyperpigmentation, hyperkeratosis) and cancer (lung, bladder)
231
Cadmium poisoning presents with:
- obstructive lung disease - renal tubule damage - skeletal abnormalities with calcium loss - osteoporosis and osteomalacia in post-menopausal women *cause: toxicity due to ROS generation
232
Major nutritional deficiencies with alcohol abuse include what?
vitamin B6, Magnesium, thiamine, folic acid, phosphorus
233
Binge drinking is defined as how many drinks for men and women?
Binge drinking , defined as four standard alcoholic drinks on one occasion for women and five drinks for men
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Unintentional/intentional injuries are more common in:
men
235
What is the difference between hematoma, subdural hematoma, and epidural hematoma?
Hematoma: collection of blood in soft tissue Subdural: blood between inner surface of dura mater and surface of brain Epidural hematoma: collectino of blood between inner surface of skull and dura
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Hard contact gunshot wounds (ex. GSW to the head) can cause what?
severe tearing and disruption of tissue leading to jagged and gaping wound (blow back)
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What is the most common chemical asphyxiant?
carbon monoxide
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Accumulations (infiltrations) of substances in cells are caused by four general types of abnormal mechanisms. What are they?
1) insufficient removal of normal substance because of altered configuration or transport 2) accumulation due to protein folding defects, transport, or abnormal degradation 3) inadequate metabolism of an endogenous substance (usually because of lack of enzyme) 4) harmful exogenous materials
239
Excess cellular water accumulation leads to what?
- cellular swelling and pallor | - vacuolation
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Excess cellular lipid/carb accumulation leads to what?
- neuro deficits - progressive disorders - vacuolation pushes organelles to the side - common in spleen, liver, CNS
241
Excess cellular glycogen accumulation leads to what?
- glycogen storage disease/diseases affecting glucose and glycogen accumulation - vacuolation - detrimental to growth and development - seen in diabetes
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The most immediate manifestations of somatic death is:
Complete cessation of respiration and circulation
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Excessive cellular protein accumulation leads to what?
- crowds organelles which disrupt function and intracellular communication - primarily accumulates in epithelial cells of renal tubules, B lymphocytes - may reuslt in proteinuria
244
What is melanin
brown-black pigment derived from tyrosine amino acid and synthesized by melanocytes; stored in melanosomes
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Albinism
congenital inherited disorder characterized by complete or partial absence of melanin (high risk of skin cancer)
246
What are hemoproteins?
essential endogenous pigments (Hb, cytochromes)
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Hemosiderosis
transient localized deposit or iron (where bruising occurs); blood vessels ruptured
248
Degradation of Hb in bruises changes in to a variety of colours. Which pigments are responsible for the following? 1) red-blue 2) green 3) yellow 4) golden brown
1) hemoglobin 2) biliverdin 3) bilirubin 4) hemosiderin
249
Iron is stored in the tissue cells in two forms. What are they?
Ferritin | Hemosiderin (yellow brown pigment)
250
Iron overload is also known as
hemachromatosis
251
Jaundice (icterus) is caused by what pigment in excess?
bilirubin
252
Define extravasation
The leakage of blood, lymph, or other fluid, such as an anticancer drug, from a blood vessel or tube into the tissue around it.
253
What is dystrophic calcification
calcification occurring in dying/necrotic tissues (common in chronic pulmonary TB; also in lymph nodes, advanced atherosclerosis, injured heart valves) - in heart valves, it presents as a heart murmur
254
What is metastatic calcification
mineral deposits occuring in undamaged, normal tissues secondary to hypercalcemia
255
Describe the following features of a cell undergoing necrosis: 1) cell size 2) nucleus 3) plasma membrane 4) cellular components 5) adjacent inflammation 6) physiologic or pathologic role
1) cell swelling 2) nucleus shrinks (pyknosis) which fragments into nuclear dust (keryorrhexis) and then finally breaksdown of chromatin (karolysis) 3) membrane disrupted 4) cellular contents digested and may leak out of cell 5) frequent adjacent inflammation 6) always pathologic
256
Describe the following features of a cell undergoing apoptosis: 1) cell size 2) nucleus 3) plasma membrane 4) cellular components 5) adjacent inflammation 6) physiologic or pathologic role
1) cell shrinking 2) fragmentation to nucleosome-size fragments 3) intact but altered plasma membrane 4) intact cell contents, may be released in apoptotic bodies 5) no adjacent inflammation 6) often physiologic role but may be pathologic wih some cell injury types
257
True or false. Cells die long before any necrotic changes are noted.
True
258
What is dysregulated apoptosis?
excessive or insufficient apoptosis (can be malfunctioning and encourage survivial of abnormal cells or lead to autoimmune disorders)
259
What are the major forms of autophagy?
Macroautophagy: aka "autophagy" and is where cytosol parts are sequestered and transported in a vacuole Microautophagy: inward invagination of lysosomal membrane for cargo delivery Chaperone-mediated autophagy: chaperone-dependent proteins that direct cargo across lysosomal membrane
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Senescence
process leading to permanent proliferative arrest of cells in response to various stressors
261
What degenerative extracellular changes occur with aging?
- binding of collagen - increased free radicals - alterations to MSK system - development of CV diseases, oxidative stress
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What occurs during cellular aging?
- atrophy, decreased function, loss of cells - compensatory mechanisms: hypertrophy/hyperplasia - damage to cell memebrane, genetic material, progression of common diseases (cancer, diabetes, heart failure)
263
What occurs during tissue and systemic aging?
- progressive stiffness and rigidity (affects arterial, pulmonary, and MSK) - sarcopenia
264
A patient presents with increased susceptibility to falls, disability, disease and death. A general term to describe this syndrome is called?
frailty syndrome
265
Which of the following male-female differences re: aging is true? 1) men have more muscle muss so may be protective against frailty 2) testosterone and GH can provide advantages to men re: muscle mass maintenance 3) cortisol is dysregulated especially in older women 4) all of the above are true
all are true
266
Define cachexia
weakness and wasting of body due to severe chronic illness
267
Define decomposition
body organic matter broken down into elemental matter to be recycled into the earth
268
Define skeletonization
final stage of death (7th stage) where skeleton is exposed due to body degradation and decay
269
Define fossilization
rare 8th stage, bones are infiltrated and replaced with inorganic mineral deposits
270
What is the net filtration equation?
forces favouring filtration - forces opposing filtration
271
Cerebral, pulmonary, and laryngeal edema are common examples of (localized/generalized) edema.
localized
272
True or false. Edema causes wounds to heal more slowly and increase risk of infection or decubiti.
True
273
The region where edematous fluid accumulates is referred to as:
a third space (interstitial space) | - fluid trapped here cannot be used for metabolic processes or perfusion
274
True or False. A patient could be dehydrated as a result of edema
True - due to fluid being sequestered
275
What sorts of drug therapy are used for hypertension?
ACE inhibitors angiotension receptor blockers renin inhibitors ^ all of those are blocking substances that are released in the body to increase BP
276
What are the three types of natriuetic peptides?
1) Atrial Natriuretic Peptides (ANH) 2) B-type natriuretic peptide (BNP) 3) Urodilation (ANP analogue)
277
[Cl-} is inversely proportionate to what?
[HCO3-]
278
What do volume-sensitive receptors and baroreceptors do?
sense changes in blood pressure and volume (such as during dehydration)
279
True or false. Hyperchloremia is inversely related to hypernatremia.
False. [Cl-] typically follows [Na+] so if one is elevated, so will the other
280
Signs and symptoms of dehydration include all of the following except: 1) decreased skin turgor 2) elevated temperature 3) prolonged capillary refill time 4) bradycardia 5) soft eyeballs 6) sunken fontanels in infants 7) weak pulses
bradycardia (heart rate will actually increase with dehydration)
281
What is the pathophysiology behind hypernatremia?
elevated serum Na+ levels (above 145 mEq/L) leading to hypertonicity and intracellular dehydration
282
Treatment for isovolemic hypernatremia
- water PO - IV dextrose 5% in water - 0.45% NS solution
283
Treatment for hypovolemic hypernatremia
- oral fluids - salt-free IV (dextrose 5% in water) - slow fluid replacement to prevent cerebral edema
284
Treatment for hypervolemic hypernatremia
loop diuretics and treating underlying condition
285
Why are CNS signs the most serious in hypernatremia?
Due to alterations in membrane potentials and shrinking of brain cells
286
What is the pathophysiology behind hyponatremia?
decreased serum Na+ levels (<135 mEq/L) due to loss of sodium, inadequate intake, or water excess leading to dilution of sodium - cell will swell and rupture
287
What electrolyte imbalance is a major cause of morbidity/mortality in ICU and elderly?
hyponatremia, contributing factors: - due to use of diuretics to increase urine flow - dehydration (from decreased thirst) - diminished urine concentrating ability - age related changes and diseases
288
How does decreased [Na+]/hyponatremia manifest (i.e. signs and symptoms)?
- cerebral edema (inreased intracranial pressure - impaired nerve conduction and neurological changes) - cognitive deficits - gait disturbances - falls with fractures
289
Which ion maintains the resting membrane potential, facilitates glycogen and glucose deposition in liver/skeletal muscle cells, and maintains normal cardiac rhythm in skeletal/smooth muscle contraction?
K+
290
The most significant regulator of K+ is:
kidney (and then also regulated by aldosterone &insulin)
291
How does [K+] get influenced by acute acidosis/alkalosis?
Acute acidosis: accumulation of H+ in ICF so K+ shifts out to maintain ionic balance, which leads to less K+ being secreted by distal tubular cells and inrease hyperkalemia risk Acute alkalosis: dereased H+ in ICF so K+ shifts into cell, K+ secretion also inreases within distal tubular cells leading to increased hypokalemia risk
292
How does aldosterone regulate increased potassium levels?
1) increased potassium stimulates release of renin by JG cells in kidney leading to aldosterone release 2) aldosterone stimulates secretion of K+ into urine by distal renal tubules and also increases K+ secretion from sweat glands
293
How does insulin regulate K+?
insulin is released after eating which drives K+ uptake into liver and muscle cells by stimulating Na-K ATPase pumps (therefore can be used to treat hyperkalemia)
294
Define potassium adaptation
ability for body to adapt to increased levels of K+ intake over time
295
Common causes of hypokalemia?
- reduced intake or increased losses of K+ - increased movement of K+ into cells - during treatment of diabetic ketoacidosis (K+ moves out of cell due to H+ accumulation in ICF, K+ then gets excreted or taken up via insulin stimulation) - renal/GI disorders - vomiting or NG suctioning (loss of other ions lead to renal compensation, stimulating aldosterone release to take up other ions back into the body, thus excreting potassium) - K+ wasting diuretics - low plasma [Mg2+] - certain antibiotics or rare herditary defects
296
What are symptoms of hypokalemia?
Mild K+ losses are asymptomatic Severe K+ losses: neuromuscular and cardiac disorders - skeletal muscle weakness (may lead to diaphragm weakness = respiratory arrest) - various dysrhythmias due to resting membrane potential disruptions - metabolic dysfunctions
297
How does a patient with hyperkalemia present?
mild: increased neuromuscular irritability (restlessness, intestinal cramping, diarrhea) severe: decreased resting membrane potential so muscle weakness, loss of muscle tone, paralysis, V-fib, cardiac arrest - delayed cardiac conduction - bradydysrhythmias
298
Effects of hypophosphatemia
- reduced capacity for O2 transport by RBC (disturbed energy metabolism) - leukocyte and platelet dysfunction - deranged muscle and nerve function - severe: irritability, respiratory failure, convulsions, confusion, numbness, coma
299
Effects of hyperphosphatemia
- Sx related to low Ca+ levels so similar to hypocalcemia | - when prolonged: calcification of soft tissues in lungs, kidneys and joints
300
A patient presents with muscle cramps, ataxia, nystagmus, and tetany with a history of alcoholism is likely suffering from what electrolyte imbalance?
hypomagnesemia
301
Signs and symptoms of hypomagnesemia?
- skeletal smooth muscle contraction - excess nerve function - loss of deep tendon reflexes - nausea/vomiting - muscle weakness - hypotension - bradycardia - resp distress
302
``` A base (accepts/donates) H+ An acid (accepts/donates) H+ ```
base: acccepts acid: donates
303
Chemical buffer systems include what? | The chemical buffering system has an _________ response.
bicarbonate, phosphate, Hb, and protein immediate
304
Respiratory buffering system responds within:
minutes to hours
305
Renal buffering system responds within:
hours to days
306
At 7.4 pH, the ratio of bicarbonate to carbonic acid (BB/CA) is:
20:1
307
Define compensations re: acid base balance and BB/CA
adjustments of pH (so BB/CA) to maintain 20:1 ratio
308
Bicarbonate, phosphate and ammonia buffers work in which buffering system? Chemical, respiratory, or renal?
Renal
309
Briefly describe phosphate buffer mechanism in renal system.
monobasic phosphate (H2PO4-) and dibasic phosphate (HPO42-) work with Na+ to form a sodium salt, monobasic phosphate released into urine
310
Briefly describe ammonia buffer mechanism in renal system.
ammonia (NH3) and ammonium (NH4+) reversibly bind or release H+ into urine - NH4+ released into urine
311
Acidemia
arterial blood pH < 7.4
312
Alkalemia
arterial blood > 7.4 pH
313
Common causes of respiratory acidosis
- respiratory depression by drugs, head injury - paralysis of respiratory muscles - chest wall disorders - lung disorders (pneumonia, pulomnary edema,, emphysema, asthma, bronchitis)
314
Common causes of respiratory alkalosis
- hypoxemia from pulmonary disease, CHF, high altitudes - hypermetabolic states (fever, anemia, hysteria, cirrhosis, grem-negative sepsis) - improper use of mechanical ventilators
315
Signs and symptoms of respiratory acidosis include all of the following but: 1) warm, flushed skin 2) initial rapid breathing rate and then gradually more depressed 3) muscle twitching/tremors/convulsions 4) paresthesia
paresthesia
316
Signs and symptoms of respiratory alkalosis include all of the following but: 1) carpopedal spasms (spasms of han n feet) 2) cebral vasodilation 3) paresthesia 4) confusion and dizziness
2) cebral vasodilation what happens during respiratory alkalosis is cerebral vasoconstriction which then reduces cerebral blood flow
317
Why are infants more susceptable to significant changes in TBW?
due to high metabolic rate and greater body surface area
318
What causes % of TBW to decline with geriatrics?
- decreased free fat mass and muscle mass - reduced ability to regulate Na+ and water balance - kidneys less efficient at producing concentrated urine - sluggish sodium conservation responses - thirst perception impaired - loss of cog function can influence fluid intake