WGU D236 PATHOPHYSIOLOGY:
OBJECTIVE ASSESSMENT QUESTIONS
AND VERIFIED ANSWERS | LATEST
UPDATE GRADED A+
What is Starling's Law of Capillary forces?
How does this explain why a nutritionally deficient child would have edema?
- 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?
,- 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?
- 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.
, WGU BD236 Bpathophysiology BOA BExam BStudy BGuide B2023 BQuestions Band BAnswers
This Bis Bespecially Bdangerous Bin Bthe Bheart Bmuscle Band Ban Birregular Bheartbeat Bcan Bcause Ba Bheart Battack
The Bbody Buses Bthe BProtein BBuffering BSystem, BPhosphate BBuffering BSystem, Band BCarbonic BAcid-
B Bicarbonate BSystem Bto Bregulate Band Bmaintain Bhomeostatic BpH, Bwhat Bis Bthe Bconsequence Bof Ba BpH
B imbalance
- Proteins Bcontain Bmany Bacidic Band Bbasic Bgroup Bthat Bcan Bbe Baffected Bby BpH Bchanges. BAny
increase Bor Bdecrease Bin Bblood BpH Bcan Balter Bthe Bstructure Bof Bthe Bprotein B(denature), Bthereby
B
affecting Bits Bfunction Bas Bwell
B
Describe Bthe Blaboratory Bfindings Bassociated Bwith Bmetabolic Bacidosis, Bmetabolic Balkalosis, Brespiratory
B acidosis Band Brespiratory Balkalosis. B(ie Brelative BpH Band BCO2 Blevels).
- Normal BABGs B(Arterial BBlood BGases) BBlood BpH: B7.35-7.45 BPCO2: B35-45 Bmm BHg BPO2: B90-100 Bmm
Hg BHCO3-: B22-26 BmEq/L BSaO2: B95-100%
B
Respiratory Bacidosis Band Balkalosis Bare Bmarked Bby Bchanges Bin BPCO2. BHigher B= Bacidosis Band Blower B=
B alkalosis
Metabolic Bacidosis Band Balkalosis Bare Bcaused Bby Bsomething Bother Bthan Babnormal BCO2 Blevels. BThis Bcould
B include Btoxicity, Bdiabetes, Brenal Bfailure Bor Bexcessive BGI Blosses.
OBJECTIVE ASSESSMENT QUESTIONS
AND VERIFIED ANSWERS | LATEST
UPDATE GRADED A+
What is Starling's Law of Capillary forces?
How does this explain why a nutritionally deficient child would have edema?
- 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?
,- 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?
- 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.
, WGU BD236 Bpathophysiology BOA BExam BStudy BGuide B2023 BQuestions Band BAnswers
This Bis Bespecially Bdangerous Bin Bthe Bheart Bmuscle Band Ban Birregular Bheartbeat Bcan Bcause Ba Bheart Battack
The Bbody Buses Bthe BProtein BBuffering BSystem, BPhosphate BBuffering BSystem, Band BCarbonic BAcid-
B Bicarbonate BSystem Bto Bregulate Band Bmaintain Bhomeostatic BpH, Bwhat Bis Bthe Bconsequence Bof Ba BpH
B imbalance
- Proteins Bcontain Bmany Bacidic Band Bbasic Bgroup Bthat Bcan Bbe Baffected Bby BpH Bchanges. BAny
increase Bor Bdecrease Bin Bblood BpH Bcan Balter Bthe Bstructure Bof Bthe Bprotein B(denature), Bthereby
B
affecting Bits Bfunction Bas Bwell
B
Describe Bthe Blaboratory Bfindings Bassociated Bwith Bmetabolic Bacidosis, Bmetabolic Balkalosis, Brespiratory
B acidosis Band Brespiratory Balkalosis. B(ie Brelative BpH Band BCO2 Blevels).
- Normal BABGs B(Arterial BBlood BGases) BBlood BpH: B7.35-7.45 BPCO2: B35-45 Bmm BHg BPO2: B90-100 Bmm
Hg BHCO3-: B22-26 BmEq/L BSaO2: B95-100%
B
Respiratory Bacidosis Band Balkalosis Bare Bmarked Bby Bchanges Bin BPCO2. BHigher B= Bacidosis Band Blower B=
B alkalosis
Metabolic Bacidosis Band Balkalosis Bare Bcaused Bby Bsomething Bother Bthan Babnormal BCO2 Blevels. BThis Bcould
B include Btoxicity, Bdiabetes, Brenal Bfailure Bor Bexcessive BGI Blosses.
