5. Essentials of Renal Physiology Pt. III Flashcards by J L

K in Body Fluids

Normal serum [K] is ____ to 5 meq/L
Extracellular K is not bound and is freely ____.
Normal intracellular [K is ____ to 150 meq/L• ____ orders of magnitude difference

3.5
filterable
120
2

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The Nernst Equation Cares

Cell membranes from excitable tissues are more permeable to ____ than Na or Cl.
Therefore, the resting membrane potential Em is given by the Nernst’ equation:

Em =-RTln[K]i =-61.5log[K]i =-80to-90mV F [K]e [K]e

 3. Since [K]i is relatively constant, small changes in [K]e will have large changes in \_\_\_\_ and dramatic consequences in \_\_\_\_ rhythm and neuromuscular function.

• K is the major determinant of resting potential of cells
• Cause EC gradient > chemoelectrical gradient
	○ \_\_\_\_ gradient is first thing that happens
		§ Differing cxn of K+ on side to another
	○ The positive charges from K+ very rapidly builds up + charge on one side that pushes back \_\_\_\_ on the concenrtration gradient
	○ Electrical charge exits on diff scale of cxn vs normal cxn that we talked about
• K+ is the only one where there is a permeability in the d\_\_\_\_ state
	○ Other oions have huge cxn gradient (Na+, Cl-), don't have permebalityt in the resitng state
	○ Determines the resting state of excitable cells
		§ Low K outside the cell > make the few K+ go down concentration gradient, and make a molar polarized cell
			□ Hypokalemia
				® \_\_\_\_ the cell
				® Opposite happens with hyperkalemia (less K+ crosses, cell is more \_\_\_\_)
			□ Either abnormalities > lethal on the heart
				® Cardiac arrhythmia
					◊ Low K+ state > hyperpolarized > makes volt-channels more \_\_\_\_ > increases the risk for lethal tachyarrhythmia

K
Em
cardiac

conc
equally
resting
hyperpolarize
depolarized
excitable

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• Depolarize past threshold > voltage-gated channels open > create ____ to other ions (Na+, Ca++) > further depolarizes the cell > channels have a time-limit and then close > permeability goes away > open up voltage K+ channels > return the cell back to it’s resting potential > ____

perms

overshoot

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Potassium

• Input
– \_\_\_\_ (oranges, bananas, potatoes, tomatoes)
• Output
– \_\_\_\_, Renal
• Shift (Can have a BIG impact)

* Kidney is regulated; \_\_\_\_ is not
* Shift of K+ in or out of cells will have a large impact on extracellular K+ cxn

food
GI
gut

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• In and out is the ____ amount

○ Any shift in the ECF, and the ICF > ____ deal

same

big

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Major Site Of Regulation of Potassium Excretion:

• The ____

cortical collecting tubule

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Cortical collecting duct: principal cells

• Enac > allows Na+ to go in by itself > net \_\_\_\_ charge in lumen
	○ Inhiibted by \_\_\_\_
• K+ channel > allows K+ to go out > pulled out by net \_\_\_\_ charge
• Whole system stimualted by \_\_\_\_

-
amiliodarione
-
aldosterone

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Potassium - Output
• To adequately excrete potassium via the kidneys you need 3 components:

____ (ie, enough nephrons working)
____ at the cortical collecting tubule
____
Absence of any of the above can lead to ____• GFR
○ Nephrons working
• Urine flow with Na+ in it at the CCT
○ Cannot have resorbeda lot before urine got ot the CCT
• CCT swithced on by aldosterone
• Can lead to hyperkalemia in the setting of ____ K+, or cells ____ DOWN THINGS

GFR
urine flow
aldosterone
hyperkalemia

ingesting
breaking

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Elevation of both #2 and #3 can lead to K ____

• Elevate both the urine flow and ALD > wasting K+ at the site of the CCT
	○ These two things never go in same direction
		§ High \_\_\_\_  diet > flow of urine and amount of Na+ will increase
			□ ALD will be \_\_\_\_ 
			□ These two are working in \_\_\_\_  directions
		§ Salt restricted diet
			□ Volume \_\_\_\_ 
			□ ALD will be \_\_\_\_ 
			□ Proximal resoprtion of Na+ will be high > urine flow at last segment of nephron will be \_\_\_\_

wasting
salt
low
opposite
deplete
high
low

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• High ALD and high urine
○ Diuretics
§ If block Na+ resorption ____ to distal nephrone/collecting duct > K+ ____
□ Hypokalemia
® Not everyone gets it because they ____ so much K+ > they keep up with their losses
• [???]

proximal
wasting
eat

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Potassium Shift

 Shift INTO cells
• \_\_\_\_
• Beta-agonists (like albuterol)
• \_\_\_\_
• Hypo-osmolarity (acute)

Shift OUT OF cells
• ____ due to fasting (generally mild effect)
• Hyperchloremic Metoabolic Acidosis
• ____ (acute)
• Cell rupture (rhabdomyolysis, hemolysis)

	• Insulin is most clinically important; big part of treatment for \_\_\_\_
		○ Shifts K+ into cells
	• Cell rupture
		○ Breaking down
		○ Hematoma being reaborbed

insulin
hypo-osmolarity

insulinopenia
hyperosmolarity

hyperkalemia

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• Changes in EKG as hyperkalemic
○ Peaked ____ wave
• Can cause letahl ____ and can stop heart
○ Hyperkalemia puts volt gated cells in state where cannot ____
• Open heart surgery > stop heart > the way they stop is via big dose of K+ IV
• Lethal injections > K+

T
arrythmia
open

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Treatment of Hyperkalemia

Step 1: Stabilize cardiac cell membranes
-____ or calcium chloride
Step 2: SHIFT potassium back into cells
-____ (usually given with D50 to prevent hypoglycemia)
-Albuterol
-____
Step 3: Get it OUT
-____ (if kidneys working) -Sodium polystyrene sulfate (kayexalate) -____ (f kidneys not working)

• Stabilize the cell membranes
	○ Having high EC \_\_\_\_++ decreases impact of hyperkalemia
• Most impotant acute therapy is INSULIN
	○ Rapidly casues K+ to go into cell, and if normal blood sugar and give \_\_\_\_
		§ Want to avoid acute hypoglycemia
• Step 1/2 are temporizing manuevers > will give time, but will not remove K+ from the body
• Diuretics can act proximilaly in nephrone > K+ wasting
	○ In patients who are not volume deplete > give a \_\_\_\_
	○ If hypovolumeic > give \_\_\_\_, and then add a loop diuretic in
	○ K+ binders > SPS > bind K+ in the \_\_\_\_
		§ Resin that binds K+
	○ If kidneys aren't working > dilaysis

calcium gluconate
insulin
sodium bicarbonate

fursosemide
dialysis

Ca
loop
saline
gut

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Treatment of Hypokalemia
• Give ____
• (but don’t give too much too ____) • ‘Nuff said

* Give K+ too fast > cardioplegic > deadly
* Slow > challenge to those who are losing a lot of K+ due to diarrhea

potassium

fast

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Why Do We Care?

• [H+] is very ____ regulated
• H+ ions are small; they associate closely with proteins and alter their function
• [H+] is regulated on a ____ scale – Normal is 40nM (pH 7.4)
– Range compatible with life is ____ nM
(pH 7.8- 6.8)

• Small > allows to get close ot proteins and affect function
	○ Proteins feel presence of protons acutely
• Up until now, everything has been on the mM scale (1000th), and now we're on nM (billionth)
	○ Huge difference in cxn
• Narrow range compatible with life because in nM!

tightly
nanomolar
15-150

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pH: A Stupid Unit Invented to Deal With All the Zero’s

• pH = -log[H+]
• Acid: substance that increases [H+] 
– Lowers pH
• Base: substance that decreases [H+] 
– Increases pH

• The unit is not \_\_\_\_; going from .1 change is different
	○ Going from 7.0 to 7.1 > different change than from 7.1 to 7.2 because it's a log scale

proportional

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Most acid > ____ (2.0)

* Anything below ____ > lowest a human can survive; and once above ____ inconsistent with life

stomach contents

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Challenge For The Body
• [H+] is on nanomolar scale
• Normal diet and metabolism adds ____ of H+ to the body
– 1 millimole = 1 million nanomoles

millimoles

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cahllenge for the body

• Nm scale of ph, add/sbstatct acid on mM scale
	○ Diet is 10 mM of acid per day > need to have kidney excrete 70 mM of H+ per day to stay in steady state
	○ Kreb cycle generating CO2 > make 15,000 mM per day
		§ Every CO2 is a potential acid
	○ A lot of acid generated in something that must be \_\_\_\_ and fixed

low

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HA H++A-
• Buffers require a ____ (HA) and a ____ (A- )
• Acid and base loads are handled by changing between these two forms to prevent large changes in free [H+]

* Add acid to system > excess anion > can bind the acid and drive equil to the left > no free proton that can assoc to protein
* If opposite > lose proton > equil to right > donate a proton to the system

hydrogen donor

hydrogen acceptor

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Characteristics of an Ideal Buffer

In sufficient quantity, that it can “absorb” the acid-base load and keep the pH ____ over a wide range of potential insults
The ____ (base) and donating pair in the buffer are in approximately equal quantity
The ____ of your acid base pair should be near your ideal pH• Add acid, pH is dropped a lttle, but most is bound by buffer until you run out and then you drop very quickly

stable
acceptor
pKa

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BODY BUFFERS

• ECF buffers
– \_\_\_\_/carbonic acid/CO2
• H+ + HCO3– H2CO3 CO2 + H2O 
– Plasma proteins
– Inorganic \_\_\_\_

• ICF buffers
– ____ (red blood cells)
– Proteins
– Inorganic____

• ____ (potentially very large buffer reservoir)
– Releases NaHCO3, KHCO3, CaCO3, CaHPO4 in response to acid load
– Accounts for up to ____% of acute acid/base buffering

	• CO2 is in equil with bicarb and a. Proton 
	• Buffers inside cells
	• Bone is a large buffer
		○ HA in bone does a lot of buffering
	• Only know about bicarb buffer system
		○ The others are dificult to measure

bicarbonate
phosphate
hemoglobi
phosphate
bone
40

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• ____ very unstable > impossible to find because changes between the two states
○ Often left out when describing the equilibrium
• Carbonic anhydrase
○ ____ (PCT) and cytosoloic forms
• The bicarb is present on chem 7
○ Measure every single day ebcasue its importantt acid base balalnce

H2CO2

luminal

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• \_\_\_\_ is how the CO2 is measured
		○ Not same as \_\_\_\_ CO2
		○ Must multiply by factor to get dissolved
	• Normal pH of 7.4
	• Do not memorize equation/do math

pCO2

dissolved

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HCO3–/H2CO3 Buffer System Why is it so important? * One component (____) is tightly regulated by the kidneys * The other component (CO2) is independently regulated by the ____ (i.e., it is an “open” buffer system—the solution containing the buffer equilibrates with the environment) * ____ measured * Most ____ extracellular buffer • Has features that aren't present in other buffer systems • Impact by two organ systems ○ Two safety valves • Bicarb ○ Regualted by the kidneys (resorbing, and also generate) • CO2 ○ Regualted by the lungs § Rate in which breathe > determiend by the need to get rid of CO2 • Creates an open buffer system > in equil with the outside world > makes buffer more ____ • Easily measure because can measure stuff in blood

``` HCO3- lung easily abundant powerful ```

• A liter of fluid that has a PCO2 40mmHg (normal); HCO3 24 (normal); and a normal pH • If removed the buffers (no bicarb) ○ The pH would be ____

• Add buffer and close system > and no movement of fluid ○ Add acid > will be buffered by bicarb > goes down to 14 § The protons are sucked up by bicarb > equil to th e ____ § Closed > CO2 staying insdi eteh box > push equil back to the ____ □ The pH will be ____ □ Still below what is seen in the rang ecompatbaile with life • Turn into an open system ○ Fix the concentration at 40 (CO2) § Will be sept by gas (same as breathing) § CO2 ____ pushing equil to the right; a BETTER job buffering □ pH will be ____ § Bicarb is the same > ever so slightly different □ The same as difference in + cxn □ Will be slightly lower in the open system because going to the ____

``` left right 6.2 not 7.2 left ```

This is how we get rid of all the CO2 generated by the krebs cycle • Retain CO2 > quickly the pCO2 will lead to generation of acid and bicarb > protons affect proteins > in trouble ○ Will survive a monthish • pCO2 in air is close to 0, mix ore outside air with gas generated in alvoeli > bring mor eamibent air > lower the ____ in the avlolaer gas > the pCO2 is determiend by the ____ > breath faster > allow lungs ot ompentsat eofr ____ being added to the body ○ Compensation will make pH be better ○ Lower pCO2 further > can bring the pH up to ____ ○ Bicarb did NOT increase; it actually would've ____ as a result of compensation • Lungs set the ____; kidneys restore the ____

``` pCO2 ventilation acid 7.3 decreased CO2 bicarb ```

“Compensation”: does not restore the ____ Lungs: set the ____ Kidneys: restore the ____

bicarbonate pCO2 bicarbonate

Henderson-hasselbach • pH is determiend by ____ over ____

kidney | lung

Henderson-Hasselbalch Applied • Bottom Line – Rise in HCO3- causes a rise in ____ – Drop in HCO3- causes a drop in ____ – Rise in CO2 causes a decrease in ____ – Drop in CO2 causes a rise in ____ * Inc bicarb and no other change > pH rise > more alkaline > fewer protons * Drop bicarb and no change > drop pH > more protons

pH pH pH pH

Respiratory Mechanisms • Exhaling ____ is an excellent way to rid the body of acid, specifically volatile acids (Recall: CO2 + H20 ↔ H2CO3 ↔ H+ + HCO3-) • Alveolar ventilation can be ____ rapidly • The pH of the body influences the rate of alveolar ventilation – ↓ pH triggers increased ____, more CO2 is lost, [H+] decreases and pH ____ – ↑pH triggers decreased ventilation, ____ accumulate, [H+] increases and pH ____ • Acid > stimulate more ventilation > breathe faster > pH goes up • Alkaline > inhibit breathing > drive pH back down • Overdose of opiates > high doses > inhibits ability to detect acidemia > stop breathing > hypercarbic and hypoxic ○ Antidote: narcan > rapid rescue bc causes them to breathe

``` carbon dioxide titrated ventilation rises CO2 falls ```

How to Increase Ventilation 1. Increase ____ of Breathing 2. Increase ____ of Breathing • Both = Kussmaul breathing= seen in severe ____

rate depth acidoses

Kidney Has Two Jobs Regarding HCO3– Balance 1. Prevent ____ of filtered HCO3- 2. “Create” new ____ * Protons that have sulfates and + charge > metabolized > generate acid > destroys ____ * Segment of nephron resorbs filtered bicarb > ____

loss HCO3 bicarb proximal

Prevention of HCO3– Loss * HUGE amount of HCO3– filtered daily * Almost all is resorbed in the ____

proximal tubule

``` Promixal tubule ' • Na/H exhcnager • Na in and proton goes out • Proton with bicarb • Luminal CA • ____ into cell > spltis into + and bicarb • ____into urine • ____ leaves the cell ```

CO2 proton bicarb

HCO3– Resorption Rest of the Nephron: Weak Sauce * If HCO3– resorption in proximal tubule is disrupted, then the rest of the nephron cannot “____” * Onc ebicarb is past PCT > poorly abosbre danion > difficulty getting out of ____

catch up | urine

Carbonic Anhydrase Inhibitors: Lower Serum [HCO3–] * Inhibit the CA then you can cause biarb wasting > will be in ____ and exit body bc the nprhon cannot catch up witht elack of bicarb absorption in th eproximal tubule * CA inhibitor is the only diuretic that would have taken > going into high altitude to compensate for low pCO2

urine

“Creating” New HCO3– * Kidney needs to pump ____ into the urine * Where does this happen? * ____ * Here come another couple of slides from the sodium lecture • Make the urine acidic ○ CCT - site of interaction with Na, K and acid base physology

H+ | cortical collecting tubule

Remember Question: • What if you wanted to reabsorb Na+, but the anion it was paired with was not resorbable? • You would have a ____

cation exchanger

Principal Cells Help Process by Making Lumen Negative, But Do NOT Have H+ Pumps • Prinicipal cells ○ Make the lumen negative by allowing Na+ to traveld own cxn grdaient and allow K+ to leave but don’t have channels that facilitate ____ to leave ○ Most comonly found cell in renal tubule/epithleium • Intercalated cells ○ Separate ○ Differne tmorphologies > will focus on ____ (ecerteting acid) § Can change in alkemia ○ Alpha § Two pumps § Every other channels is a passive channgel; this is th eone palce where there's another pump that burns ____ itself □ Up the cxn gradient § ____ ATPase § ____ ATPase § Most quanitfyabtlae important.> ____ ATPase □ Majority of pumping □ CO2 inside cell >sppit into proton and bicarb > take H+ and pump inot ____ > leave a bicarb that stays in obdy ® Good enough?

``` H+ alpha ATP H+ H/K H+ lumen ```

Alpha-Intercalated Cells Establish H+ Gradient • The ____is the major proton pump for these cells – H+/K+ ATPase has minimal role • Able to establish pH of ____ in the urine even though pH is 7.4 in the blood • But: – pH of 4.4 is only 0.04mMol [H+] per liter – Kidney typically has to get rid of 70 mMol/day! – How does kidney do this? ``` • One liter of urine is getting rid of 0.04 mmol ○ Need to get rid of 70 mmol per day > would have to make 100's of liters of urine in order to get rid of enough protons ○ What else? § BUFFER! □ Buffer in urine □ ____ (excess in food) □ Only one regulated: ® ____ (NH4+) ```

H+ ATPase 4.4 phosphate ammonium

Buffers • Many of the substances the kidney excretes are also buffers – ____ is a major one • Only one is these buffers is regulated: – ____(NH4+)

phosphate | ammonium

Proximal Tubule Makes NH3 from Glutamine to Buffer H+ • Prox tubule cell > ____ ATPase • Cell also takes AA (____) > generates ____ > goes into urine ○ If no acid urine in distal tubule > ammonium reasborbed > ____ > undo work of proximal tubule in generating it ○ MAKE AMMONIA IN PROX, BUT TRAP IN THE ____ § Pumping + into with ATPase, suck up proton with ammonia > ammonium > no longer pushign on cxn gradient on the pump that's tryig to ush more protons out

``` Na/H glutamine ammonia metabolized CCT ```

Handling of NH3 and NH4+ in the Tubule is Complicated * NH4+ can be reabsorbed in the tubule and then later ____ * If pH is not acid in the distal tubule, then NH4+ will be reabsorbed and “undo” the work of the ____ * Take-Home message is that the distal tubule “traps” in the tubule by secreting ____

secreted proximal tuule proton

``` Three Things Needed for Kidney To Excrete Acid Generated by Metabolism 1. Reclaim all filtered ____ 2. Make urine pH ____ 3. Create sufficient ____ (ammonium) ``` • Missing one of three things > will not be in completley ____status

bicarbonate low buffer normal acid-base

Four Step Process 1. What’s the “____”? 2. What’s the “____”? 3. Is there appropriate ____? 4. Is there a widened ____?

emia osis compensation anion gap

Definitions: “emia” • “-emia” refers to the actual ECF ____ – “Normalemia”: ____pH (7.38–7.42) – Acidemia: ____ pH (<7.38) – Alkalemia: ____ pH (>7.42) • Determined by pH from ____ • A patient can have only ____ “emia” at a time • Blood gas - tells about CO2 and O2 in blood at th esame time • Emia is where you are in acid-base land > one place at particualr time ○ As opposed ot an osis which is a process

``` pH normal low high blood gas one ```

What The Heck Is An “Osis”? | • An “osis” are process that changes ____

Processes that change pH * Acidosis: ____ [H+] * Alkalosis: takes ____ [H+] • May have started middle > acidosis > two steps to the right > acidemia ○ Can also have severe osis, but also an alkalosis > and can end up in the same psot

adds | away

``` • Acidosis: ____ [H+] • Alkalosis: takes ____ [H+] • Respiratory “osis > changes ____ • Metabolic “osis” > changes ____ • Each “osis” has its appropriate ____ – Metabolic “osis”> ____ – Respiratory “osis” > ____ ```

``` adds away pCO2 [HCO3-] compensation respiratory compensation metabolic compensation ```

“Osis” versus “Emia” • “...osis” is a ____ – Acidosis: respiratory, metabolic – Alkalosis: respiratory, metabolic – Can have ____ than one at a time (maximum ____) – Does not tell us the ____ of the blood • “...emia” indicates the change in blood ____ – Acidemia: pH < 7.35 – Alkalemia: pH > 7.45 – Does not tell us ____ we got there – Can only be ____ pH at a time! • If acidemic, you know at a minimum that you have an acidosis ○ But do not know what kind, how many, etc. ○ And same applies for alkalemic

process more 3 pH pH how one

Respiratory Alkalosis • pCO2 less than ____ mm Hg (____) • Most ____ acid- base imbalance • Primary cause is ____ • Things that make you breathe fast ○ Causes RA • Not clinically detected/significant ○ Do not check a ____ for these people if something else wrogn isn't present

``` 40 hypocapnea common hyperventilation blood gas ```

Respiratory Acidosis • ____ levels of CO2 – CO2>____mmHg. • Hypercapnia – high levels of ____ in blood • Typically due to airway compromise resulting in ____ – classic is ____. * Acute and sudden * Can be lethal in the face of taking heroin/fentynl IV

``` elevated 40 CO2 hypoventilation COPD ```

Metabolic Acidosis | • Increased [H+] because of drop in ____

[HCO3-]

Why Metabolic Acidosis Occurs Usually one of three processes: 1. ____ of acids (acids produced faster than they can be excreted) § Abnormal metabolism: ____, ketoacidosis § Substances that cause acid generation: ____, methanol, ethylene glycol 2. Loss of ____ (bicarb) directly § GI: ____ (most common) § Renal: Proximal Renal Tubular Acidosis (RTA) 3. Lack of ____ of new base § Low ____ excretion (____ RTA) * Lactic acidosis > no ____ of vital organs * Ketoacidosis > insufficient ____ to undergo normal metabolism * Sialyclic acid (aspirin) > works by inhibitng normal metbaolism > alctone/ketone generation * Abnormal alcohols > mebtaolized to formate/ox acid * Low ammonium can be due to not making enough, or not having th e____ that pushes it up the cxn gradient

``` overproduction lactic acidosis salicylates base diarrhea synthesis ammonium ``` perfusion insulin pump

Overproduction of Acids • They All “Leave Behind” a ____: HA > H+ +A-

conjugate anion

The “Anion Gap” [Na] + [Unmeasured Cation] = [Bicarb]+ [Cl] + [Unmeasured Anion] [Na] - [Bicarb]- [Cl] = [Unmeasured Anion] – [Unmeasured Cation] [____] - [____]- [____] = Anion gap Usually this gap is a set amount of unmeasured anions (we assume unmeasured cations are negligible) When the gap increases above 10, this suggests the addition of an ____ in an amount noted equivalent to the increase in the gap • Differenc ebt measrued cations and anions • Not a lot of measured cations other than Na+ • Antions ar eclhoride and bicarb • Anions are usaully slight in difference ○ Anion gap = ____ anions ○ There are anions there, but they're not measured anions • NEEDED (not noted) • Anion gap widened (> 10 meq/L) ○ Calling card of an acid that's been added to the body

``` Na bicarb Cl acid unmeasured ```

Most Important Causes of Gap Acidosis * ____ * Ketoacidosis * ____ * Toxic alcohols

lactic acidosis | salicylate

Metabolic Alkalosis • Bicarbonate ____ - concentration in blood is greater than 24 mEq/L ``` • Causes: – Excess ____ = loss of stomach acid – Endocrine disorders – particularly ____ – Heavy ingestion of ____ – Severe ____ ``` • Remove HCl > leaving behind bicarb ○ Acid generated by splitting CO2 and H+ ○ The H+ comes back in, or the bicarb will be secreted into the GI • CCT secreting protons; if CCT is upregualted by aldo, then more + into the urine, and will leave ____ behind • Antacids have bicarbs in them • Severe volume depletion via NaCl

``` excess vomiting hyperaldosteronism antacids volume depletion bicarb ```

Compensation • If underlying problem is metabolic > – Bicarbonate < 24 = ____ (nml bicarb ~24) – Bicarbonate > 24 = ____ – Respiratory compensation by either increasing or decreasing ventilation and as a result, altering ____ • If problem is respiratory > – CO2 < 40 = ____ (nml CO2 ~ 40) – CO2 >40 = ____ – Increased ventilation, increases CO2 ____ and reduces the CO2 – metabolic compensation by either increasing or decreasing ____ excretion • Compensation never fully ____ the underlying abnormality

``` acidosis alkalosis CO2 alkalosis acidosis excretion acid corrects ```

Compensation for Metabolic Acidosis • Increased ventilation – The expected respiratory compensation is given by the formula (aka ____ formula): – Expected pCO2 (on ABG) = 1.5 ([HCO3]) + 8 􏰂2 – Winter’s formula only works for ____ • There are other compensation equations, but they are beyond the focus of today’s talk * Gives the expected ____ compensation * Each acid-base disorder has it's own compensation equation

Winter's respiratory alkalosis respiratory

ACID-BASE DISTURBANCES SUMMARIZED Resp acidosis Primary disturbance: ____ CO2 Compensation: ____ HCO3- Resp alkalosis Primary disturbance: ____ CO2 Compensation: ____ HCO3- Metabolic acidosis Primary disturbance: ____ HCO3- Compensation: ____ CO2 Metabolic alkalosis Primary disturbance: ____ HCO3- Compensation: ____ CO2

inc inc dec dec dec dec inc inc

Strategy for Analyzing Acid-Base Problems How to identify the primary disorder 1. Look at ____ • Acidemia • Alkalemia 2. Look at pCO2 (acid) • High pCO2 ® ____ • Low pCO2 ® ____ 3. Look at HCO3- (base) • High HCO3- ® ____ • Low HCO3- ® ____ 4. Look for ____

pH respiratoyr acidosis respiratory alkalosis metabolic alkalosis metabolic acidosis compensation

Strategy for Analyzing Acid-Base problems • Always calculate the ____ • To identify a mixed acid-base disorder, assess whether compensation is appropriate: – If a metabolic acidosis is present, calculate the expected pCO2 using ____ Arterial blood gas: ____ / pCO2 / ____

anion gap | winter's formula

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5. Essentials of Renal Physiology Pt. III Flashcards

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