WGU PATHOPHYSIOLOGY D236 2022-2023
Starling's Law describes how fluids move across the cap-
1. What is Star-
illary membrane. There are two major opposing forces
ling's Law
that act to balance each other, hydrostatic pressure
of Capillary
(pushing water out of the capillaries) and osmotic pres-
forces?
sure (including oncontic pressure, which pushes fluid into
the capillaries).
How does this
explain why a
Both electrolytes and proteins (oncontic pressure) in the
nutritionally defi-
blood affect osmotic pressure, high electrolyte and protein
cient child would
concentrations in the blood would cause water to leave
have edema?
the cells and interstitial space and enter the blood stream
to dilute the high concentrations.
On, the other hand, low electrolyte and protein concen-
trations (as seen in a nutritionally deficient child) would
cause water to leave the capillaries and enter the cells
and interstitial fluid which can lead to edema.
A drop in blood pressure is sensed by the kidneys by low
2. How does the
perfusion, which in turn begins to secrete renin.
RAAS
(Renin-An-
Renin then triggers the liver to produce angiotensinogen,
giotensin-Aldos-
which is converted to Angiotensin I in the lungs and then
terone System)
angiotensin II by the enzyme
result in
increased blood
Angiotensin-converting enzyme (ACE). Angiotensin II
volume and
stimulates peripheral arterial vasoconstriction which rais-
increased blood
es BP.
pressure?
Angiotensin II is also stimulating the adrenal gland to
release aldosterone, which acts to increase sodium and
water reabsorption increasing blood volume, while also
increased potassium secretion in urine.
Normal levels of potassium are between 3.5 and 5.2
3. How can hyper-
mEq/dL. Hyperkalemia refers to potassium levels higher
kalemia lead to
that 5.2 mEq/dL.
cardiac arrest?
A major function of potassium is to conduct nerve impuls-
, WGU PATHOPHYSIOLOGY D236 2022-2023
es in muscles. Too low and muscle weakness occurs and
too much can cause muscle spasms.
This is especially dangerous in the heart muscle and an
irregular heartbeat can cause a heart attack
4. The body uses Proteins contain many acidic and basic group that can
the Protein be affected by pH changes. Any increase or decrease in
Buffering Sys- blood pH can alter the structure of the protein (denature),
tem, Phosphate thereby affecting its function as well
Buffering Sys-
tem, and Car-
bonic Acid-Bi-
carbonate Sys-
tem to regu-
late and maintain
homeostatic pH,
what is the con-
sequence of a pH
imbalance
5. Describe the lab- Normal ABGs (Arterial Blood Gases) Blood pH: 7.35-7.45
oratory findings PCO2: 35-45 mm Hg PO2: 90-100 mm Hg HCO3-: 22-26
associated with mEq/L SaO2: 95-100%
metabolic acido-
sis, metabolic al- Respiratory acidosis and alkalosis are marked by
kalosis, respira- changes in PCO2. Higher = acidosis and lower = alkalo-
tory acidosis and sis
respiratory alka-
losis. (ie relative Metabolic acidosis and alkalosis are caused by some-
pH and CO2 lev- thing other than abnormal CO2 levels. This could include
els). toxicity, diabetes, renal failure or excessive GI losses.
Here are the rules to follow to determine if is respiratory
or metabolic in nature. -If pH and PCO2 are moving in
opposite directions, then it is the pCO2 levels that are
causing the imbalance and it is respiratory in nature.
, WGU PATHOPHYSIOLOGY D236 2022-2023
-If PCO2 is normal or is moving in the same direction as
the pH, then the imbalance is metabolic in nature.
6. The anion gap The anion gap is the calculation of unmeasured anions in
is the difference the blood.
between mea-
sured cations Lactic acid and ketones both lead to the production of
(Na+ and K+) unmeasured anions, which remove HCO3- (a measured
and measured anion) due to buffering of the excess H+ and therefore
anions (Cl- and leads to an increase in the AG.
HCO3-), this cal-
culation can be
useful in deter-
mining the cause
of metabolic aci-
dosis.
Why would an
increased anion
gap be observed
in diabetic ke-
toacidosis or lac-
tic acidosis?
7. Why is it im- Insulin is the hormone responsible for initiating the uptake
portant to main- of glucose by the cells. Cells use glucose to produce
tain a homeostat- energy (ATP).
ic balance of glu-
cose in the blood In a normal individual, when blood glucose increases, the
(ie describe the pancreas is signaled to produced in insulin, which binds
pathogenesis of to insulin receptors on a cells surface and initiates the
diabetes)? uptake of glucose.
Glucose is a very reactive molecule and if left in the blood,
it can start to bind to other proteins and lipids, which can
lead to loss of function.
AGEs are advanced glycation end products that are a re-
, WGU PATHOPHYSIOLOGY D236 2022-2023
sult of glucose reacting with the endothelial lining, which
can lead to damage in the heart and kidneys.
8. Compare and Type I diabetes is caused by lack of insulin. With out
contrast Type I insulin signaling, glucose will not be taken into the cell
and Type II Dia- and leads to high blood glucose (hyperglycemia). Type I
betes is usually treated with insulin injections.
Type II diabetes is caused by a desensitization to insulin
signaling. The insulin receptors are no longer responding
to insulin, which also leads to hyperglycemia.
Type II is usually treated with drugs to increase the
sensitization to insulin (metformin), dietary and life-style
changes or insulin injections.
9. Describe some AEIOU-acidosis. Electrolytes, Intoxication/Ingestion,
reasons for a overload, uremia. Patients with kidney or heart failure.
patient needing
dialysis A build up of phosphates, urea and magnesium are re-
moved from the blood using a semi-permeable mem-
brane and dialysate.
AEIOU:
A—acidosis;
E—electrolytes principally hyperkalemia; I—
ingestions or overdose of medications/drugs;
O—overload of fluid causing heart failure; U—
uremia leading to encephalitis/pericarditis
10. Compare and Hemodialysis uses a machine to pump blood from the
contrast he- body in one tube while dialysate (made of water, elec-
modialysis and trolytes and salts) is pumped in the separate tube in the
peritoneal dialy- opposite direction. Waste from the blood diffuses through
sis. the semipermeable membrane separating the blood from
the dialysate.
What are some
reasons for a Peritoneal Dialysis does not use a machine, but instead
patient choosing injects a solution of water and glucose into the abdominal
Starling's Law describes how fluids move across the cap-
1. What is Star-
illary membrane. There are two major opposing forces
ling's Law
that act to balance each other, hydrostatic pressure
of Capillary
(pushing water out of the capillaries) and osmotic pres-
forces?
sure (including oncontic pressure, which pushes fluid into
the capillaries).
How does this
explain why a
Both electrolytes and proteins (oncontic pressure) in the
nutritionally defi-
blood affect osmotic pressure, high electrolyte and protein
cient child would
concentrations in the blood would cause water to leave
have edema?
the cells and interstitial space and enter the blood stream
to dilute the high concentrations.
On, the other hand, low electrolyte and protein concen-
trations (as seen in a nutritionally deficient child) would
cause water to leave the capillaries and enter the cells
and interstitial fluid which can lead to edema.
A drop in blood pressure is sensed by the kidneys by low
2. How does the
perfusion, which in turn begins to secrete renin.
RAAS
(Renin-An-
Renin then triggers the liver to produce angiotensinogen,
giotensin-Aldos-
which is converted to Angiotensin I in the lungs and then
terone System)
angiotensin II by the enzyme
result in
increased blood
Angiotensin-converting enzyme (ACE). Angiotensin II
volume and
stimulates peripheral arterial vasoconstriction which rais-
increased blood
es BP.
pressure?
Angiotensin II is also stimulating the adrenal gland to
release aldosterone, which acts to increase sodium and
water reabsorption increasing blood volume, while also
increased potassium secretion in urine.
Normal levels of potassium are between 3.5 and 5.2
3. How can hyper-
mEq/dL. Hyperkalemia refers to potassium levels higher
kalemia lead to
that 5.2 mEq/dL.
cardiac arrest?
A major function of potassium is to conduct nerve impuls-
, WGU PATHOPHYSIOLOGY D236 2022-2023
es in muscles. Too low and muscle weakness occurs and
too much can cause muscle spasms.
This is especially dangerous in the heart muscle and an
irregular heartbeat can cause a heart attack
4. The body uses Proteins contain many acidic and basic group that can
the Protein be affected by pH changes. Any increase or decrease in
Buffering Sys- blood pH can alter the structure of the protein (denature),
tem, Phosphate thereby affecting its function as well
Buffering Sys-
tem, and Car-
bonic Acid-Bi-
carbonate Sys-
tem to regu-
late and maintain
homeostatic pH,
what is the con-
sequence of a pH
imbalance
5. Describe the lab- Normal ABGs (Arterial Blood Gases) Blood pH: 7.35-7.45
oratory findings PCO2: 35-45 mm Hg PO2: 90-100 mm Hg HCO3-: 22-26
associated with mEq/L SaO2: 95-100%
metabolic acido-
sis, metabolic al- Respiratory acidosis and alkalosis are marked by
kalosis, respira- changes in PCO2. Higher = acidosis and lower = alkalo-
tory acidosis and sis
respiratory alka-
losis. (ie relative Metabolic acidosis and alkalosis are caused by some-
pH and CO2 lev- thing other than abnormal CO2 levels. This could include
els). toxicity, diabetes, renal failure or excessive GI losses.
Here are the rules to follow to determine if is respiratory
or metabolic in nature. -If pH and PCO2 are moving in
opposite directions, then it is the pCO2 levels that are
causing the imbalance and it is respiratory in nature.
, WGU PATHOPHYSIOLOGY D236 2022-2023
-If PCO2 is normal or is moving in the same direction as
the pH, then the imbalance is metabolic in nature.
6. The anion gap The anion gap is the calculation of unmeasured anions in
is the difference the blood.
between mea-
sured cations Lactic acid and ketones both lead to the production of
(Na+ and K+) unmeasured anions, which remove HCO3- (a measured
and measured anion) due to buffering of the excess H+ and therefore
anions (Cl- and leads to an increase in the AG.
HCO3-), this cal-
culation can be
useful in deter-
mining the cause
of metabolic aci-
dosis.
Why would an
increased anion
gap be observed
in diabetic ke-
toacidosis or lac-
tic acidosis?
7. Why is it im- Insulin is the hormone responsible for initiating the uptake
portant to main- of glucose by the cells. Cells use glucose to produce
tain a homeostat- energy (ATP).
ic balance of glu-
cose in the blood In a normal individual, when blood glucose increases, the
(ie describe the pancreas is signaled to produced in insulin, which binds
pathogenesis of to insulin receptors on a cells surface and initiates the
diabetes)? uptake of glucose.
Glucose is a very reactive molecule and if left in the blood,
it can start to bind to other proteins and lipids, which can
lead to loss of function.
AGEs are advanced glycation end products that are a re-
, WGU PATHOPHYSIOLOGY D236 2022-2023
sult of glucose reacting with the endothelial lining, which
can lead to damage in the heart and kidneys.
8. Compare and Type I diabetes is caused by lack of insulin. With out
contrast Type I insulin signaling, glucose will not be taken into the cell
and Type II Dia- and leads to high blood glucose (hyperglycemia). Type I
betes is usually treated with insulin injections.
Type II diabetes is caused by a desensitization to insulin
signaling. The insulin receptors are no longer responding
to insulin, which also leads to hyperglycemia.
Type II is usually treated with drugs to increase the
sensitization to insulin (metformin), dietary and life-style
changes or insulin injections.
9. Describe some AEIOU-acidosis. Electrolytes, Intoxication/Ingestion,
reasons for a overload, uremia. Patients with kidney or heart failure.
patient needing
dialysis A build up of phosphates, urea and magnesium are re-
moved from the blood using a semi-permeable mem-
brane and dialysate.
AEIOU:
A—acidosis;
E—electrolytes principally hyperkalemia; I—
ingestions or overdose of medications/drugs;
O—overload of fluid causing heart failure; U—
uremia leading to encephalitis/pericarditis
10. Compare and Hemodialysis uses a machine to pump blood from the
contrast he- body in one tube while dialysate (made of water, elec-
modialysis and trolytes and salts) is pumped in the separate tube in the
peritoneal dialy- opposite direction. Waste from the blood diffuses through
sis. the semipermeable membrane separating the blood from
the dialysate.
What are some
reasons for a Peritoneal Dialysis does not use a machine, but instead
patient choosing injects a solution of water and glucose into the abdominal
