WGU D236 pathophysiology: Objective As
l l l l
sessment Questions and Verified Answers |
l l l l l l
Latest 2023/2024 GRADEDA+
l l l
WhatlislStarling'slLawloflCapillarylforces?
Howldoeslthislexplainlwhylalnutritionallyldeficientlchildlwouldlhaveledema?
-
l ☑️☑️Starling'sl Lawl describesl howl fluidsl movel acrossl thel capillaryl membrane.l Therel arel twolmajorlopposinglforc
eslthatlactltolbalanceleachlother,lhydrostaticlpressurel(pushinglwaterloutloflthelcapillaries)landlosmoticlp
ressurel(includinglonconticlpressure,lwhichlpusheslfluidlintolthelcapillaries).
Bothlelectrolyteslandlproteinsl(onconticlpressure)linlthelbloodlaffectlosmoticlpressure,lhighlele
ctrolytelandlproteinlconcentrationslinlthelbloodlwouldlcauselwaterltolleavelthelcellslandlintersti
tiallspacelandlenterlthelbloodlstreamltoldilutelthelhighlconcentrations.
On,lthelotherlhand,llowlelectrolytelandlproteinlconcentrationsl(aslseenlinlalnutritionallyldeficientlchild)lw
ouldlcauselwaterltolleavelthelcapillarieslandlenterlthelcellslandlinterstitiallfluidlwhichlcanlleadltoledema.
HowldoeslthelRAASl(Renin-Angiotensin-
AldosteronelSystem)lresultlinlincreasedlbloodlvolumelandlincreasedlbloodlpressure?
,WGUlD236lpathophysiologylOAlExamlStudylGuidel2023lQuestionslandlAnswers
-l☑️☑️Aldroplinl bloodl pressurelislsensedlbyl thel kidneysl byl lowl perfusion,l whichlinlturnlbeginsl tolsecretelrenin.
Reninlthenltriggerslthelliverltolproducelangiotensinogen,lwhichlislconvertedltolAngiotensinlIlinlthellungslan
dlthenlangiotensinlIIlbylthelenzyme
Angiotensin-
convertinglenzymel(ACE).lAngiotensinlIIlstimulateslperipherallarteriallvasoconstrictionlwhichlraiseslBP.
AngiotensinlIIlislalsolstimulatingltheladrenallglandltolreleaselaldosterone,lwhichlactsltolincreaselsodiumla
ndlwaterlreabsorptionlincreasinglbloodlvolume,lwhilelalsolincreasedlpotassiumlsecretionlinlurine.
Howlcanlhyperkalemialleadltolcardiaclarrest?
-
l ☑️☑️Normall levelsl ofl potassiuml arel betweenl 3.5l andl 5.2l mEq/dL.l Hyperkalemial refersl topotassiumllevelslhighe
rlthatl5.2lmEq/dL.
Almajorlfunctionloflpotassiumlisltolconductlnervelimpulseslinlmuscles.lToollowlandlmusclelweaknessloccur
slandltoolmuchlcanlcauselmusclelspasms.
,WGUlD236lpathophysiologylOAlExamlStudylGuidel2023lQuestionslandlAnswers
Thislislespeciallyldangerouslinlthelheartlmusclelandlanlirregularlheartbeatlcanlcauselalheartlattack
ThelbodyluseslthelProteinlBufferinglSystem,lPhosphatelBufferinglSystem,landlCarboniclAcid-
BicarbonatelSystemltolregulatelandlmaintainlhomeostaticlpH,lwhatlislthelconsequenceloflalpHlimbalance
l
- ☑️☑️ProteinslcontainlmanylacidiclandlbasiclgrouplthatlcanlbelaffectedlbylpHlchanges.lAnylincreaselorldecreaseli
nlbloodlpHlcanlalterlthelstructureloflthelproteinl(denature),ltherebylaffectinglitslfunctionlaslwell
Describelthellaboratorylfindingslassociatedlwithlmetaboliclacidosis,lmetaboliclalkalosis,lrespiratorylacidosisla
ndlrespiratorylalkalosis.l(ielrelativelpHlandlCO2llevels).
- ☑️☑️Normall ABGsl(Arteriall Bloodl Gases)l Bloodl pH:l 7.35-7.45l PCO2:l 35-45l mml Hgl PO2:l 90-100l mmlHglHCO3-
:l22-26lmEq/LlSaO2:l95-100%
RespiratorylacidosislandlalkalosislarelmarkedlbylchangeslinlPCO2.lHigherl=lacidosislandllowerl=lalkalosis
MetaboliclacidosislandlalkalosislarelcausedlbylsomethinglotherlthanlabnormallCO2llevels.lThislcouldlincludelt
oxicity,ldiabetes,lrenallfailurelorlexcessivelGIllosses.
, WGUlD236lpathophysiologylOAlExamlStudylGuidel2023lQuestionslandlAnswers
Herelarelthelrulesltolfollowltoldetermineliflislrespiratorylorlmetaboliclinlnature.l-
IflpHlandlPCO2larelmovinglinloppositeldirections,lthenlitlislthelpCO2llevelslthatlarelcausinglthelimbalancela
ndlitlislrespiratorylinlnature.
-IflPCO2lislnormallorlislmovinglinlthelsameldirectionlaslthelpH,lthenlthelimbalancelislmetaboliclinlnature.
Thelanionlgaplisltheldifferencelbetweenlmeasuredlcationsl(Na+landlK+)landlmeasuredlanionsl(Cl-
andlHCO3-),lthislcalculationlcanlbelusefullinldetermininglthelcauseloflmetaboliclacidosis.
l
Whylwouldlanlincreasedlanionlgaplbelobservedlinldiabeticlketoacidosislorllacticlacidosis?
- ☑️☑️Thel anionl gapl isl thel calculationl ofl unmeasuredl anionsl inl thel blood.
Lacticlacidlandlketoneslbothlleadltolthelproductionloflunmeasuredlanions,lwhichlremovelHCO3-
(almeasuredlanion)ldueltolbufferingloflthelexcesslH+landlthereforelleadsltolanlincreaselinlthelAG.
l
Whylislitlimportantltolmaintainlalhomeostaticlbalanceloflglucoselinlthelbloodl(ieldescribelthelpathogenesislofl
diabetes)?
- ☑️☑️Insulinlislthelhormonelresponsiblel forl initiatingl theluptakeloflglucoselbyl thelcells.l Cellsluselglucoselt
olproducelenergyl(ATP).
l l l l
sessment Questions and Verified Answers |
l l l l l l
Latest 2023/2024 GRADEDA+
l l l
WhatlislStarling'slLawloflCapillarylforces?
Howldoeslthislexplainlwhylalnutritionallyldeficientlchildlwouldlhaveledema?
-
l ☑️☑️Starling'sl Lawl describesl howl fluidsl movel acrossl thel capillaryl membrane.l Therel arel twolmajorlopposinglforc
eslthatlactltolbalanceleachlother,lhydrostaticlpressurel(pushinglwaterloutloflthelcapillaries)landlosmoticlp
ressurel(includinglonconticlpressure,lwhichlpusheslfluidlintolthelcapillaries).
Bothlelectrolyteslandlproteinsl(onconticlpressure)linlthelbloodlaffectlosmoticlpressure,lhighlele
ctrolytelandlproteinlconcentrationslinlthelbloodlwouldlcauselwaterltolleavelthelcellslandlintersti
tiallspacelandlenterlthelbloodlstreamltoldilutelthelhighlconcentrations.
On,lthelotherlhand,llowlelectrolytelandlproteinlconcentrationsl(aslseenlinlalnutritionallyldeficientlchild)lw
ouldlcauselwaterltolleavelthelcapillarieslandlenterlthelcellslandlinterstitiallfluidlwhichlcanlleadltoledema.
HowldoeslthelRAASl(Renin-Angiotensin-
AldosteronelSystem)lresultlinlincreasedlbloodlvolumelandlincreasedlbloodlpressure?
,WGUlD236lpathophysiologylOAlExamlStudylGuidel2023lQuestionslandlAnswers
-l☑️☑️Aldroplinl bloodl pressurelislsensedlbyl thel kidneysl byl lowl perfusion,l whichlinlturnlbeginsl tolsecretelrenin.
Reninlthenltriggerslthelliverltolproducelangiotensinogen,lwhichlislconvertedltolAngiotensinlIlinlthellungslan
dlthenlangiotensinlIIlbylthelenzyme
Angiotensin-
convertinglenzymel(ACE).lAngiotensinlIIlstimulateslperipherallarteriallvasoconstrictionlwhichlraiseslBP.
AngiotensinlIIlislalsolstimulatingltheladrenallglandltolreleaselaldosterone,lwhichlactsltolincreaselsodiumla
ndlwaterlreabsorptionlincreasinglbloodlvolume,lwhilelalsolincreasedlpotassiumlsecretionlinlurine.
Howlcanlhyperkalemialleadltolcardiaclarrest?
-
l ☑️☑️Normall levelsl ofl potassiuml arel betweenl 3.5l andl 5.2l mEq/dL.l Hyperkalemial refersl topotassiumllevelslhighe
rlthatl5.2lmEq/dL.
Almajorlfunctionloflpotassiumlisltolconductlnervelimpulseslinlmuscles.lToollowlandlmusclelweaknessloccur
slandltoolmuchlcanlcauselmusclelspasms.
,WGUlD236lpathophysiologylOAlExamlStudylGuidel2023lQuestionslandlAnswers
Thislislespeciallyldangerouslinlthelheartlmusclelandlanlirregularlheartbeatlcanlcauselalheartlattack
ThelbodyluseslthelProteinlBufferinglSystem,lPhosphatelBufferinglSystem,landlCarboniclAcid-
BicarbonatelSystemltolregulatelandlmaintainlhomeostaticlpH,lwhatlislthelconsequenceloflalpHlimbalance
l
- ☑️☑️ProteinslcontainlmanylacidiclandlbasiclgrouplthatlcanlbelaffectedlbylpHlchanges.lAnylincreaselorldecreaseli
nlbloodlpHlcanlalterlthelstructureloflthelproteinl(denature),ltherebylaffectinglitslfunctionlaslwell
Describelthellaboratorylfindingslassociatedlwithlmetaboliclacidosis,lmetaboliclalkalosis,lrespiratorylacidosisla
ndlrespiratorylalkalosis.l(ielrelativelpHlandlCO2llevels).
- ☑️☑️Normall ABGsl(Arteriall Bloodl Gases)l Bloodl pH:l 7.35-7.45l PCO2:l 35-45l mml Hgl PO2:l 90-100l mmlHglHCO3-
:l22-26lmEq/LlSaO2:l95-100%
RespiratorylacidosislandlalkalosislarelmarkedlbylchangeslinlPCO2.lHigherl=lacidosislandllowerl=lalkalosis
MetaboliclacidosislandlalkalosislarelcausedlbylsomethinglotherlthanlabnormallCO2llevels.lThislcouldlincludelt
oxicity,ldiabetes,lrenallfailurelorlexcessivelGIllosses.
, WGUlD236lpathophysiologylOAlExamlStudylGuidel2023lQuestionslandlAnswers
Herelarelthelrulesltolfollowltoldetermineliflislrespiratorylorlmetaboliclinlnature.l-
IflpHlandlPCO2larelmovinglinloppositeldirections,lthenlitlislthelpCO2llevelslthatlarelcausinglthelimbalancela
ndlitlislrespiratorylinlnature.
-IflPCO2lislnormallorlislmovinglinlthelsameldirectionlaslthelpH,lthenlthelimbalancelislmetaboliclinlnature.
Thelanionlgaplisltheldifferencelbetweenlmeasuredlcationsl(Na+landlK+)landlmeasuredlanionsl(Cl-
andlHCO3-),lthislcalculationlcanlbelusefullinldetermininglthelcauseloflmetaboliclacidosis.
l
Whylwouldlanlincreasedlanionlgaplbelobservedlinldiabeticlketoacidosislorllacticlacidosis?
- ☑️☑️Thel anionl gapl isl thel calculationl ofl unmeasuredl anionsl inl thel blood.
Lacticlacidlandlketoneslbothlleadltolthelproductionloflunmeasuredlanions,lwhichlremovelHCO3-
(almeasuredlanion)ldueltolbufferingloflthelexcesslH+landlthereforelleadsltolanlincreaselinlthelAG.
l
Whylislitlimportantltolmaintainlalhomeostaticlbalanceloflglucoselinlthelbloodl(ieldescribelthelpathogenesislofl
diabetes)?
- ☑️☑️Insulinlislthelhormonelresponsiblel forl initiatingl theluptakeloflglucoselbyl thelcells.l Cellsluselglucoselt
olproducelenergyl(ATP).
