WGU PATHOPHYSIOLOGY D236 EXAM
WITH COMPLETE SOLUTIONS
What ris rStarling's rLaw rof rCapillary rforces? r
How rdoes rthis rexplain rwhy ra rnutritionally rdeficient rchild rwould rhave redema? r-
rcorrect ranswers-Starling's rLaw rdescribes rhow rfluids rmove racross rthe rcapillary
rmembrane. rThere rare rtwo rmajor ropposing rforces rthat ract rto rbalance reach
rother, rhydrostatic rpressure r(pushing rwater rout rof rthe rcapillaries) rand rosmotic
rpressure r(including roncontic rpressure, rwhich rpushes rfluid rinto rthe rcapillaries). r
,Both relectrolytes rand rproteins r(oncontic rpressure) rin rthe rblood raffect rosmotic
rpressure, rhigh relectrolyte rand rprotein rconcentrations rin rthe rblood rwould rcause
rwater rto rleave rthe rcells rand rinterstitial rspace rand renter rthe rblood rstream rto
rdilute rthe rhigh rconcentrations. r
On, rthe rother rhand, rlow relectrolyte rand rprotein rconcentrations r(as rseen rin ra
rnutritionally rdeficient rchild) rwould rcause rwater rto rleave rthe rcapillaries rand renter
rthe rcells rand rinterstitial rfluid rwhich rcan rlead rto redema.
How rdoes rthe rRAAS r(Renin-Angiotensin-Aldosterone rSystem) rresult rin rincreased
rblood rvolume rand rincreased rblood rpressure? r- rcorrect ranswers-A rdrop rin rblood
rpressure ris rsensed rby rthe rkidneys rby rlow rperfusion, rwhich rin rturn rbegins rto
rsecrete rrenin. r
Renin rthen rtriggers rthe rliver rto rproduce rangiotensinogen, rwhich ris rconverted rto
rAngiotensin rI rin rthe rlungs rand rthen rangiotensin rII rby rthe renzyme r
Angiotensin-converting renzyme r(ACE). rAngiotensin rII rstimulates rperipheral rarterial
rvasoconstriction rwhich rraises rBP. r
Angiotensin rII ris ralso rstimulating rthe radrenal rgland rto rrelease raldosterone, rwhich
racts rto rincrease rsodium rand rwater rreabsorption rincreasing rblood rvolume, rwhile
ralso rincreased rpotassium rsecretion rin rurine.
How rcan rhyperkalemia rlead rto rcardiac rarrest? r- rcorrect ranswers-Normal rlevels rof
rpotassium rare rbetween r3.5 rand r5.2 rmEq/dL. rHyperkalemia rrefers rto rpotassium
rlevels rhigher rthat r5.2 rmEq/dL. r
A rmajor rfunction rof rpotassium ris rto rconduct rnerve rimpulses rin rmuscles. rToo rlow
rand rmuscle rweakness roccurs rand rtoo rmuch rcan rcause rmuscle rspasms. r
This ris respecially rdangerous rin rthe rheart rmuscle rand ran rirregular rheartbeat rcan
rcause ra rheart rattack
The rbody ruses rthe rProtein rBuffering rSystem, rPhosphate rBuffering rSystem, rand
rCarbonic rAcid-Bicarbonate rSystem rto rregulate rand rmaintain rhomeostatic rpH,
rwhat ris rthe rconsequence rof ra rpH rimbalance r- rcorrect ranswers-Proteins rcontain
rmany racidic rand rbasic rgroup rthat rcan rbe raffected rby rpH rchanges. rAny
rincrease ror rdecrease rin rblood rpH rcan ralter rthe rstructure rof rthe rprotein
r(denature), rthereby raffecting rits rfunction ras rwell
Describe rthe rlaboratory rfindings rassociated rwith rmetabolic racidosis, rmetabolic
ralkalosis, rrespiratory racidosis rand rrespiratory ralkalosis. r(ie rrelative rpH rand rCO2
rlevels). r- rcorrect ranswers-Normal rABGs r(Arterial rBlood rGases) rBlood rpH: r7.35-
7.45 rPCO2: r35-45 rmm rHg rPO2: r90-100 rmm rHg rHCO3-: r22-26 rmEq/L rSaO2:
r95-100% r
,Respiratory racidosis rand ralkalosis rare rmarked rby rchanges rin rPCO2. rHigher r=
racidosis rand rlower r= ralkalosis r
Metabolic racidosis rand ralkalosis rare rcaused rby rsomething rother rthan rabnormal
rCO2 rlevels. rThis rcould rinclude rtoxicity, rdiabetes, rrenal rfailure ror rexcessive rGI
rlosses. r
Here rare rthe rrules rto rfollow rto rdetermine rif ris rrespiratory ror rmetabolic rin rnature.
r-If rpH rand rPCO2 rare rmoving rin ropposite rdirections, rthen rit ris rthe rpCO2 rlevels
rthat rare rcausing rthe rimbalance rand rit ris rrespiratory rin rnature. r
-If rPCO2 ris rnormal ror ris rmoving rin rthe rsame rdirection ras rthe rpH, rthen rthe
rimbalance ris rmetabolic rin rnature.
The ranion rgap ris rthe rdifference rbetween rmeasured rcations r(Na+ rand rK+) rand
rmeasured ranions r(Cl- rand rHCO3-), rthis rcalculation rcan rbe ruseful rin rdetermining
rthe rcause rof rmetabolic racidosis. r
Why rwould ran rincreased ranion rgap rbe robserved rin rdiabetic rketoacidosis ror
rlactic racidosis? r- rcorrect ranswers-The ranion rgap ris rthe rcalculation rof
runmeasured ranions rin rthe rblood. r
Lactic racid rand rketones rboth rlead rto rthe rproduction rof runmeasured ranions,
rwhich rremove rHCO3- r(a rmeasured ranion) rdue rto rbuffering rof rthe rexcess rH+
rand rtherefore rleads rto ran rincrease rin rthe rAG.
Why ris rit rimportant rto rmaintain ra rhomeostatic rbalance rof rglucose rin rthe rblood
r(ie rdescribe rthe rpathogenesis rof rdiabetes)? r- rcorrect ranswers-Insulin ris rthe
rhormone rresponsible rfor rinitiating rthe ruptake rof rglucose rby rthe rcells. rCells ruse
rglucose rto rproduce renergy r(ATP). r
In ra rnormal rindividual, rwhen rblood rglucose rincreases, rthe rpancreas ris rsignaled
rto rproduced rin rinsulin, rwhich rbinds rto rinsulin rreceptors ron ra rcells rsurface rand
rinitiates rthe ruptake rof rglucose. r
Glucose ris ra rvery rreactive rmolecule rand rif rleft rin rthe rblood, rit rcan rstart rto rbind
rto rother rproteins rand rlipids, rwhich rcan rlead rto rloss rof rfunction. r
AGEs rare radvanced rglycation rend rproducts rthat rare ra rresult rof rglucose rreacting
rwith rthe rendothelial rlining, rwhich rcan rlead rto rdamage rin rthe rheart rand rkidneys.
Compare rand rcontrast rType rI rand rType rII rDiabetes r- rcorrect ranswers-Type rI
rdiabetes ris rcaused rby rlack rof rinsulin. rWith rout rinsulin rsignaling, rglucose rwill rnot
rbe rtaken rinto rthe rcell rand rleads rto rhigh rblood rglucose r(hyperglycemia). rType rI
ris rusually rtreated rwith rinsulin rinjections. r
, Type rII rdiabetes ris rcaused rby ra rdesensitization rto rinsulin rsignaling. rThe rinsulin
rreceptors rare rno rlonger rresponding rto rinsulin, rwhich ralso rleads rto
rhyperglycemia. r
Type rII ris rusually rtreated rwith rdrugs rto rincrease rthe rsensitization rto rinsulin
r(metformin), rdietary rand rlife-style rchanges ror rinsulin rinjections.
Describe rsome rreasons rfor ra rpatient rneeding rdialysis r- rcorrect ranswers-AEIOU-
acidosis. rElectrolytes, rIntoxication/Ingestion, roverload, ruremia. rPatients rwith rkidney
ror rheart rfailure. r
A rbuild rup rof rphosphates, rurea rand rmagnesium rare rremoved rfrom rthe rblood
rusing ra rsemi-permeable rmembrane rand rdialysate. r
AEIOU: r
A—acidosis; r
E—electrolytes rprincipally rhyperkalemia; r
I—ingestions ror roverdose rof rmedications/drugs; r
O—overload rof rfluid rcausing rheart rfailure; r
U—uremia rleading rto rencephalitis/pericarditis
Compare rand rcontrast rhemodialysis rand rperitoneal rdialysis. r
What rare rsome rreasons rfor ra rpatient rchoosing rone rover rthe rother? r- rcorrect
ranswers-Hemodialysis ruses ra rmachine rto rpump rblood rfrom rthe rbody rin rone
rtube rwhile rdialysate r(made rof rwater, relectrolytes rand rsalts) ris rpumped rin rthe
rseparate rtube rin rthe ropposite rdirection. rWaste rfrom rthe rblood rdiffuses rthrough
rthe rsemipermeable rmembrane rseparating rthe rblood rfrom rthe rdialysate. r
Peritoneal rDialysis rdoes rnot ruse ra rmachine, rbut rinstead rinjects ra rsolution rof
rwater rand rglucose rinto rthe rabdominal rcavity. rThe rperitoneum racts ras rthe
rmembrane rinstead rof rdialysis rtubing. rThe rwaste rproducts rdiffuse rinto rthe
rabdominal rcavity rand rthe rwaste rsolution ris rthen rdrained rfrom rthe rbody. r
Peritoneal rdialysis roffers rcontinuous rfiltration rand ris rless rdisruption rto rthe
rpatient's rdaily rroutines. rHowever, rit rdoes rrequire rsome rtraining rof rthe rpatient
rand ris rnot rrecommended rfor rindividuals rwho rare roverweight ror rhave rsevere
rkidney rfailure. r
Hemodialysis rprovides rmedical rcare, rbut r3 rtimes ra rweek rfor rseveral rhours rsitting
rat ra rhospital ror rclinic. rIndividuals rwith racute rkidney rfailure rare rrecommended rto
ruse rhemodialysis.
How rdoes rhomeostasis rand rmaintaining roptimal rphysiological rhealth rimpact ryour
rwellbeing? r- rcorrect ranswers-Homeostasis racts rto rcreate ra rconstant rand rstable
WITH COMPLETE SOLUTIONS
What ris rStarling's rLaw rof rCapillary rforces? r
How rdoes rthis rexplain rwhy ra rnutritionally rdeficient rchild rwould rhave redema? r-
rcorrect ranswers-Starling's rLaw rdescribes rhow rfluids rmove racross rthe rcapillary
rmembrane. rThere rare rtwo rmajor ropposing rforces rthat ract rto rbalance reach
rother, rhydrostatic rpressure r(pushing rwater rout rof rthe rcapillaries) rand rosmotic
rpressure r(including roncontic rpressure, rwhich rpushes rfluid rinto rthe rcapillaries). r
,Both relectrolytes rand rproteins r(oncontic rpressure) rin rthe rblood raffect rosmotic
rpressure, rhigh relectrolyte rand rprotein rconcentrations rin rthe rblood rwould rcause
rwater rto rleave rthe rcells rand rinterstitial rspace rand renter rthe rblood rstream rto
rdilute rthe rhigh rconcentrations. r
On, rthe rother rhand, rlow relectrolyte rand rprotein rconcentrations r(as rseen rin ra
rnutritionally rdeficient rchild) rwould rcause rwater rto rleave rthe rcapillaries rand renter
rthe rcells rand rinterstitial rfluid rwhich rcan rlead rto redema.
How rdoes rthe rRAAS r(Renin-Angiotensin-Aldosterone rSystem) rresult rin rincreased
rblood rvolume rand rincreased rblood rpressure? r- rcorrect ranswers-A rdrop rin rblood
rpressure ris rsensed rby rthe rkidneys rby rlow rperfusion, rwhich rin rturn rbegins rto
rsecrete rrenin. r
Renin rthen rtriggers rthe rliver rto rproduce rangiotensinogen, rwhich ris rconverted rto
rAngiotensin rI rin rthe rlungs rand rthen rangiotensin rII rby rthe renzyme r
Angiotensin-converting renzyme r(ACE). rAngiotensin rII rstimulates rperipheral rarterial
rvasoconstriction rwhich rraises rBP. r
Angiotensin rII ris ralso rstimulating rthe radrenal rgland rto rrelease raldosterone, rwhich
racts rto rincrease rsodium rand rwater rreabsorption rincreasing rblood rvolume, rwhile
ralso rincreased rpotassium rsecretion rin rurine.
How rcan rhyperkalemia rlead rto rcardiac rarrest? r- rcorrect ranswers-Normal rlevels rof
rpotassium rare rbetween r3.5 rand r5.2 rmEq/dL. rHyperkalemia rrefers rto rpotassium
rlevels rhigher rthat r5.2 rmEq/dL. r
A rmajor rfunction rof rpotassium ris rto rconduct rnerve rimpulses rin rmuscles. rToo rlow
rand rmuscle rweakness roccurs rand rtoo rmuch rcan rcause rmuscle rspasms. r
This ris respecially rdangerous rin rthe rheart rmuscle rand ran rirregular rheartbeat rcan
rcause ra rheart rattack
The rbody ruses rthe rProtein rBuffering rSystem, rPhosphate rBuffering rSystem, rand
rCarbonic rAcid-Bicarbonate rSystem rto rregulate rand rmaintain rhomeostatic rpH,
rwhat ris rthe rconsequence rof ra rpH rimbalance r- rcorrect ranswers-Proteins rcontain
rmany racidic rand rbasic rgroup rthat rcan rbe raffected rby rpH rchanges. rAny
rincrease ror rdecrease rin rblood rpH rcan ralter rthe rstructure rof rthe rprotein
r(denature), rthereby raffecting rits rfunction ras rwell
Describe rthe rlaboratory rfindings rassociated rwith rmetabolic racidosis, rmetabolic
ralkalosis, rrespiratory racidosis rand rrespiratory ralkalosis. r(ie rrelative rpH rand rCO2
rlevels). r- rcorrect ranswers-Normal rABGs r(Arterial rBlood rGases) rBlood rpH: r7.35-
7.45 rPCO2: r35-45 rmm rHg rPO2: r90-100 rmm rHg rHCO3-: r22-26 rmEq/L rSaO2:
r95-100% r
,Respiratory racidosis rand ralkalosis rare rmarked rby rchanges rin rPCO2. rHigher r=
racidosis rand rlower r= ralkalosis r
Metabolic racidosis rand ralkalosis rare rcaused rby rsomething rother rthan rabnormal
rCO2 rlevels. rThis rcould rinclude rtoxicity, rdiabetes, rrenal rfailure ror rexcessive rGI
rlosses. r
Here rare rthe rrules rto rfollow rto rdetermine rif ris rrespiratory ror rmetabolic rin rnature.
r-If rpH rand rPCO2 rare rmoving rin ropposite rdirections, rthen rit ris rthe rpCO2 rlevels
rthat rare rcausing rthe rimbalance rand rit ris rrespiratory rin rnature. r
-If rPCO2 ris rnormal ror ris rmoving rin rthe rsame rdirection ras rthe rpH, rthen rthe
rimbalance ris rmetabolic rin rnature.
The ranion rgap ris rthe rdifference rbetween rmeasured rcations r(Na+ rand rK+) rand
rmeasured ranions r(Cl- rand rHCO3-), rthis rcalculation rcan rbe ruseful rin rdetermining
rthe rcause rof rmetabolic racidosis. r
Why rwould ran rincreased ranion rgap rbe robserved rin rdiabetic rketoacidosis ror
rlactic racidosis? r- rcorrect ranswers-The ranion rgap ris rthe rcalculation rof
runmeasured ranions rin rthe rblood. r
Lactic racid rand rketones rboth rlead rto rthe rproduction rof runmeasured ranions,
rwhich rremove rHCO3- r(a rmeasured ranion) rdue rto rbuffering rof rthe rexcess rH+
rand rtherefore rleads rto ran rincrease rin rthe rAG.
Why ris rit rimportant rto rmaintain ra rhomeostatic rbalance rof rglucose rin rthe rblood
r(ie rdescribe rthe rpathogenesis rof rdiabetes)? r- rcorrect ranswers-Insulin ris rthe
rhormone rresponsible rfor rinitiating rthe ruptake rof rglucose rby rthe rcells. rCells ruse
rglucose rto rproduce renergy r(ATP). r
In ra rnormal rindividual, rwhen rblood rglucose rincreases, rthe rpancreas ris rsignaled
rto rproduced rin rinsulin, rwhich rbinds rto rinsulin rreceptors ron ra rcells rsurface rand
rinitiates rthe ruptake rof rglucose. r
Glucose ris ra rvery rreactive rmolecule rand rif rleft rin rthe rblood, rit rcan rstart rto rbind
rto rother rproteins rand rlipids, rwhich rcan rlead rto rloss rof rfunction. r
AGEs rare radvanced rglycation rend rproducts rthat rare ra rresult rof rglucose rreacting
rwith rthe rendothelial rlining, rwhich rcan rlead rto rdamage rin rthe rheart rand rkidneys.
Compare rand rcontrast rType rI rand rType rII rDiabetes r- rcorrect ranswers-Type rI
rdiabetes ris rcaused rby rlack rof rinsulin. rWith rout rinsulin rsignaling, rglucose rwill rnot
rbe rtaken rinto rthe rcell rand rleads rto rhigh rblood rglucose r(hyperglycemia). rType rI
ris rusually rtreated rwith rinsulin rinjections. r
, Type rII rdiabetes ris rcaused rby ra rdesensitization rto rinsulin rsignaling. rThe rinsulin
rreceptors rare rno rlonger rresponding rto rinsulin, rwhich ralso rleads rto
rhyperglycemia. r
Type rII ris rusually rtreated rwith rdrugs rto rincrease rthe rsensitization rto rinsulin
r(metformin), rdietary rand rlife-style rchanges ror rinsulin rinjections.
Describe rsome rreasons rfor ra rpatient rneeding rdialysis r- rcorrect ranswers-AEIOU-
acidosis. rElectrolytes, rIntoxication/Ingestion, roverload, ruremia. rPatients rwith rkidney
ror rheart rfailure. r
A rbuild rup rof rphosphates, rurea rand rmagnesium rare rremoved rfrom rthe rblood
rusing ra rsemi-permeable rmembrane rand rdialysate. r
AEIOU: r
A—acidosis; r
E—electrolytes rprincipally rhyperkalemia; r
I—ingestions ror roverdose rof rmedications/drugs; r
O—overload rof rfluid rcausing rheart rfailure; r
U—uremia rleading rto rencephalitis/pericarditis
Compare rand rcontrast rhemodialysis rand rperitoneal rdialysis. r
What rare rsome rreasons rfor ra rpatient rchoosing rone rover rthe rother? r- rcorrect
ranswers-Hemodialysis ruses ra rmachine rto rpump rblood rfrom rthe rbody rin rone
rtube rwhile rdialysate r(made rof rwater, relectrolytes rand rsalts) ris rpumped rin rthe
rseparate rtube rin rthe ropposite rdirection. rWaste rfrom rthe rblood rdiffuses rthrough
rthe rsemipermeable rmembrane rseparating rthe rblood rfrom rthe rdialysate. r
Peritoneal rDialysis rdoes rnot ruse ra rmachine, rbut rinstead rinjects ra rsolution rof
rwater rand rglucose rinto rthe rabdominal rcavity. rThe rperitoneum racts ras rthe
rmembrane rinstead rof rdialysis rtubing. rThe rwaste rproducts rdiffuse rinto rthe
rabdominal rcavity rand rthe rwaste rsolution ris rthen rdrained rfrom rthe rbody. r
Peritoneal rdialysis roffers rcontinuous rfiltration rand ris rless rdisruption rto rthe
rpatient's rdaily rroutines. rHowever, rit rdoes rrequire rsome rtraining rof rthe rpatient
rand ris rnot rrecommended rfor rindividuals rwho rare roverweight ror rhave rsevere
rkidney rfailure. r
Hemodialysis rprovides rmedical rcare, rbut r3 rtimes ra rweek rfor rseveral rhours rsitting
rat ra rhospital ror rclinic. rIndividuals rwith racute rkidney rfailure rare rrecommended rto
ruse rhemodialysis.
How rdoes rhomeostasis rand rmaintaining roptimal rphysiological rhealth rimpact ryour
rwellbeing? r- rcorrect ranswers-Homeostasis racts rto rcreate ra rconstant rand rstable
