WGU D236 PATHOPHYSIOLOGY OA AND PA
2025/2026 BANK VERSION AND STUDY GUIDE |
ACTUAL EXAM QUESTIONS AND ANSWERS AND
RATIONALES | EXPERT VERIFIED FOR
GUARANTEED PASS | LATEST UPDATE /BRAND
NEW
Describe the laboratory findings associated with metabolic
acidosis, metabolic alkalosis, respiratory acidosis and
respiratory alkalosis. (ie relative pH and CO2 levels). -
✔✔ANSWER ✔✔-Normal ABGs (Arterial Blood Gases) Blood
pH: 7.35-7.45 PCO2: 35-45 mm Hg PO2: 90-100 mm Hg HCO3-:
22-26 mEq/L SaO2: 95-100%
Respiratory acidosis and alkalosis are marked by changes in
PCO2. Higher = acidosis and lower = alkalosis
Metabolic acidosis and alkalosis are caused by something other
than abnormal CO2 levels. This could include 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.
-If PCO2 is normal or is moving in the same direction as the pH,
then the imbalance is metabolic in nature.
What is Starling's Law of Capillary forces?
How does this explain why a nutritionally deficient child would
have edema? - ✔✔ANSWER ✔✔-Starling's Law describes how
fluids move across the capillary membrane. There are two
major opposing forces that act to balance each other,
hydrostatic pressure (pushing water out of the capillaries) and
osmotic pressure (including oncontic pressure, which pushes
fluid into the capillaries).
Both electrolytes and proteins (oncontic pressure) in the blood
affect osmotic pressure, high electrolyte and protein
concentrations in the blood would cause water to leave the
cells and interstitial space and enter the blood stream to dilute
the high concentrations.
,On, the other hand, low electrolyte and protein concentrations
(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.
How does the RAAS (Renin-Angiotensin-Aldosterone System)
result in increased blood volume and increased blood pressure?
- ✔✔ANSWER ✔✔-A drop in blood pressure is sensed by the
kidneys by low perfusion, which in turn begins to secrete renin.
Renin then triggers the liver to produce angiotensinogen, which
is converted to Angiotensin I in the lungs and then angiotensin
II by the enzyme
Angiotensin-converting enzyme (ACE). Angiotensin II stimulates
peripheral arterial vasoconstriction which raises BP.
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.
, How can hyperkalemia lead to cardiac arrest? - ✔✔ANSWER
✔✔-Normal levels of potassium are between 3.5 and 5.2
mEq/dL. Hyperkalemia refers to potassium levels higher that
5.2 mEq/dL.
A major function of potassium is to conduct nerve impulses 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
The body uses the Protein Buffering System, Phosphate
Buffering System, and Carbonic Acid-Bicarbonate System to
regulate and maintain homeostatic pH, what is the
consequence of a pH imbalance - ✔✔ANSWER ✔✔-Proteins
contain many acidic and basic group that can be affected by pH
changes. Any increase or decrease in blood pH can alter the
structure of the protein (denature), thereby affecting its
function as well
The anion gap is the difference between measured cations (Na+
and K+) and measured anions (Cl- and HCO3-), this calculation
can be useful in determining the cause of metabolic acidosis.
2025/2026 BANK VERSION AND STUDY GUIDE |
ACTUAL EXAM QUESTIONS AND ANSWERS AND
RATIONALES | EXPERT VERIFIED FOR
GUARANTEED PASS | LATEST UPDATE /BRAND
NEW
Describe the laboratory findings associated with metabolic
acidosis, metabolic alkalosis, respiratory acidosis and
respiratory alkalosis. (ie relative pH and CO2 levels). -
✔✔ANSWER ✔✔-Normal ABGs (Arterial Blood Gases) Blood
pH: 7.35-7.45 PCO2: 35-45 mm Hg PO2: 90-100 mm Hg HCO3-:
22-26 mEq/L SaO2: 95-100%
Respiratory acidosis and alkalosis are marked by changes in
PCO2. Higher = acidosis and lower = alkalosis
Metabolic acidosis and alkalosis are caused by something other
than abnormal CO2 levels. This could include 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.
-If PCO2 is normal or is moving in the same direction as the pH,
then the imbalance is metabolic in nature.
What is Starling's Law of Capillary forces?
How does this explain why a nutritionally deficient child would
have edema? - ✔✔ANSWER ✔✔-Starling's Law describes how
fluids move across the capillary membrane. There are two
major opposing forces that act to balance each other,
hydrostatic pressure (pushing water out of the capillaries) and
osmotic pressure (including oncontic pressure, which pushes
fluid into the capillaries).
Both electrolytes and proteins (oncontic pressure) in the blood
affect osmotic pressure, high electrolyte and protein
concentrations in the blood would cause water to leave the
cells and interstitial space and enter the blood stream to dilute
the high concentrations.
,On, the other hand, low electrolyte and protein concentrations
(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.
How does the RAAS (Renin-Angiotensin-Aldosterone System)
result in increased blood volume and increased blood pressure?
- ✔✔ANSWER ✔✔-A drop in blood pressure is sensed by the
kidneys by low perfusion, which in turn begins to secrete renin.
Renin then triggers the liver to produce angiotensinogen, which
is converted to Angiotensin I in the lungs and then angiotensin
II by the enzyme
Angiotensin-converting enzyme (ACE). Angiotensin II stimulates
peripheral arterial vasoconstriction which raises BP.
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.
, How can hyperkalemia lead to cardiac arrest? - ✔✔ANSWER
✔✔-Normal levels of potassium are between 3.5 and 5.2
mEq/dL. Hyperkalemia refers to potassium levels higher that
5.2 mEq/dL.
A major function of potassium is to conduct nerve impulses 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
The body uses the Protein Buffering System, Phosphate
Buffering System, and Carbonic Acid-Bicarbonate System to
regulate and maintain homeostatic pH, what is the
consequence of a pH imbalance - ✔✔ANSWER ✔✔-Proteins
contain many acidic and basic group that can be affected by pH
changes. Any increase or decrease in blood pH can alter the
structure of the protein (denature), thereby affecting its
function as well
The anion gap is the difference between measured cations (Na+
and K+) and measured anions (Cl- and HCO3-), this calculation
can be useful in determining the cause of metabolic acidosis.
