Renal Physiology for Lab
Cut out the characters to practice moving them into and out of the
tubules. Nutrients are green, electrolytes are yellow, waste is black,
hormones and medicines are purple.
1/3 water
2/3 water
2/3 Salt
Amino Acids
Potassium
Water
Water
Salt
Salt
Water
Water
Salt
Salt
1/3 Salt
Glucose
Potassium
Phosphate
Potassium
Magnesium
Potassium
Magnesium
2
Calcium
Calcium
Parathyroid hormone
Calcium
Hormones that regulate K+
Bicarbonate
Bicarbonate
Bicarbonate
Bicarbonate
Sodium channel blockers
Hydrogen ions
Hydrogen ions
Hydrogen ions
Hydrogen ions
Furosemide (Lasix)
Urea
Urea
Urea
Aldosterone/ADH
Glomerulus
Bowman’s capsule
Proximal convoluted tubule
(Priority City Tunnel)
Descending limb
(Disneyland)
Loop of Henle (tip)
(Low Hat Tipping)
Thick Ascending Limb
(Tall Tales movie theater)
Early Distal convoluted tubule
(Education Department)
Late Distal convoluted tubule
(Lucky District with casinos)
Collecting duct
(Criminal district)
This area has the maximally
hyperosmotic fluid when
ADH levels are high.
This area is the site of
hormonally regulated
potassium
Secretes creatinine, antibiotics,
diuretics, H+ and uric acid.
Macula densa is found here.
Tubular fluid here is hyperosmotic to
plasma, and is not hormone sensitive
Reabsorbs bicarbonate and
urea; Secretes K+
This area is impermeable to water
unless a hormone like aldosterone or
ADH allows it.
This area is acted upon
by parathyroid hormone.
No water is reabsorbed unless
ADH or aldosterone is present.
No salt is reabsorbed unless
aldosterone is present.
This area Is sensitive to sodium
channel blockers like amiloride
and aldosterone inhibitors.
Intercalated cells here
secrete hydrogen and make
“new” bicarbonate.
Is sensitive to the diuretic
furosemide (Lasix).
Capillary hydrostatic pressure
is very high here.
Reabsorbs salt and H2O
water if aldosterone and
ADH are present.
Secreted into the lumen here is
50% Urea, small amount of
sodium and water
This area is acted upon by
aldosterone and ADH
colloid osmotic pressure
here is essentially zero
Intercalated cells here
secrete hydrogen and make
“new” bicarbonate.
Print this page. Add the yellow labels on the previous page first, then run the pictures on the previous page through the tubule
and make them exit and enter at the right locations. Then place the white text boxes in the locations where they belong.
1
Glomerulus
2
Bowman’s capsule
8
Late Distal convoluted tubule
3
Proximal
convoluted
tubule
7
Early Distal
convoluted
tubule
9
Collecting duct
6
Thick Ascending Limb
4
Descending limb
5
Loop of Henle (tip)
6
1
Glomerulus
Capillary hydrostatic
pressure is very high
here.
2
Bowman’s capsule
colloid osmotic pressure
here is essentially zero
3
Proximal
convoluted
tubule
Secretes creatinine, antibiotics,
diuretics, H+ and uric acid.
7
6
Thick Ascending Limb
Is sensitive to the diuretic
furosemide (Lasix).
This area is impermeable to
water unless a hormone like
aldosterone or ADH allows it.
4
Descending limb
Secreted into the lumen here is
50% Urea, small amount of
sodium and water
5
Loop of Henle (tip)
Tubular fluid here is hyperosmotic to
plasma, and is not hormone sensitive
8
Late Distal convoluted tubule
Reabsorbs salt and H2O if
aldosterone and ADH are
present.
7
Early Distal
convoluted
tubule
Macula densa is found here.
This area is acted upon by
aldosterone and ADH
This area is acted upon
by parathyroid hormone.
This area is the site of
hormonally regulated
potassium
Intercalated cells here
secrete hydrogen and make
“new” bicarbonate.
This area Is sensitive to sodium
channel blockers like amiloride
and aldosterone inhibitors.
9
9
Collecting duct
No water is reabsorbed unless
ADH or aldosterone is present.
No salt is reabsorbed unless
aldosterone is present.
Reabsorbs bicarbonate and
urea; Secretes K+
Intercalated cells here
secrete hydrogen and make
“new” bicarbonate.
This area has the maximally
hyperosmotic fluid when
ADH levels are high.
Imagine It….
• Each of these particles is like a person who
works in a factory in Glomerulus City.
• They all leave work at 5pm and have to take
the same freeway home (the Tubular
Freeway).
• Each of them get off at different freeway exits.
11
The People
THE GOOD NUTRIENTS
Water
Salt (NaCl)
Glucose
Amino acids
THE GOOD ELECTROLYTES
Potassium (K+)
Calcium (Ca2+)
Magnesium (Mg2+)
Phosphate (PO4)
Bicarbonate (HCO3-)
H+
THE WASTE PRODUCTS
Urea
Creatinine
Antibiotics
Diuretics
Uric acid
THE LAW ENFORCEMENT OFFICIALS
Aldosterone
ADH
Parathyroid hormone
Furosemide (Lasix)
Hormones that regulate potassium (aldosterone and insulin)
Sodium channel blockers like Amiloride (a potassium sparing diuretic) and aldosterone inhibitors
12
The Freeway Exits
•
Proximal Convoluted Tubule (PCT)
–
•
Descending limb (DL)
–
•
City of Education (this is where the schools are)
Late Distal convoluted tubule (LD)
–
•
City of TALL TALES (this is where all the movie theaters are)
Early Distal convoluted tubule (ED)
–
•
City of Low Hats (and they TIP their hats to you…very polite!)
Thick Ascending Limb (TAL)
–
•
Disneyland!
Loop of Henle, tip (LOHT)
–
•
Priority City Tunnel (these people are rich and have a Fast Track pass!)
Lucky District (this is where the gambling casinos are)
Collecting duct (CD)
–
The criminal district
13
The Workers and their exits
THE GOOD NUTRIENTS
–
Salt (NaCl) (picture a salt shaker)
• PCT (2/3 leaves)
• DL (1/3 leaves)
• TAL (leaves if aldosterone present)
• ED (leaves if aldosterone present)
• LD (leaves if aldosterone present)
• CD (leaves only if aldosterone is present)
– Water (picture a water delivery man)
• PCT (2/3 of water exits)
• DL (1/3 leaves, but it could enter)
• TAL (leaves only if aldosterone or ADH present)
• ED (leaves only if aldosterone or ADH present)
• LD (leaves only if aldosterone or ADH present)
• CD (leaves only if aldosterone or ADH present)
– Glucose (picture a lollipop)
• PCT
– Amino acids (picture a cow)
• PCT
Leaving the freeway
means reabsorption
Entering the freeway
means secretion
14
The Workers and their exits
THE GOOD ELECTROLYTES
–
Potassium (K+) allows for muscle contraction (picture a body builder)
•
•
•
•
–
PCT (leaves)
DL (leaves)
LD (enters the freeway here)
CD (enters the freeway here)
Calcium (Ca2+) for strong bones (picture a skeleton)
•
•
•
–
PCT (leaves)
LOHT (leaves)
ED (leaves)
Magnesium (Mg2+) for muscle relaxation (picture a massage therapist)
•
•
–
PCT (leaves)
LOHT (leaves)
Phosphate (PO4) for ATP (picture a race car driver)
•
–
PCT (leaves)
Bicarbonate (HCO3-) (picture a fire extinguisher)
•
•
•
•
–
TAL (leaves)
ED (leaves)
LD (leaves)
CD (enters or leaves here)
H+ (picture an acid-squirting monster)
•
•
•
•
PCT (enters the freeway here)
ED (enters the freeway here)
LD (enters the freeway here)
CD (enters or leaves here)
Leaving the freeway means
reabsorption
Entering the freeway means
secretion
15
The Workers and their exits
THE WASTE PRODUCTS
–
–
–
–
–
Urea (a waste product of protein metabolism; picture a Rhea bird, similar to an ostrich)
• PCT (leaves)
• DL (enters the freeway here)
• LD (enters the freeway here)
Creatinine (a waste product of protein metabolism)
• PCT (enters the freeway here)
Antibiotics
• PCT (enters the freeway here)
Diuretics
• PCT (enters the freeway here)
Uric acid
• PCT (enters the freeway here)
Leaving the freeway
means reabsorption
Entering the freeway
means secretion
16
The Workers and their exits
HORMONES AND MEDICINES (LAW ENFORCEMENT)
–
Aldosterone
•
•
•
•
–
TAL (acts on this site)
ED (acts on this site)
LD (acts on this site)
CD (acts on this site)
ADH
•
•
•
•
–
TAL (acts on this site)
ED (acts on this site)
LD (acts on this site)
CD (acts on this site)
Sodium channel blockers like Amiloride (a potassium sparing diuretic) and aldosterone inhibitors;
(City salt monitor…no more salt allowed to leave)
•
•
•
•
–
TAL (acts on this site to prevent sodium from being reabsorbed)
ED (acts on this site to prevent sodium from being reabsorbed)
LD (acts on this site to prevent sodium from being reabsorbed)
CD (acts on this site to prevent sodium from being reabsorbed)
Parathyroid hormone (school milk man)
•
–
ED (acts at this site to increase calcium reabsorption)
Hormones that regulate potassium (aldosterone and insulin); (school banana monitor)
•
–
ED (acts on this site to cause potassium to either enter or leave)
Furosemide (Lasix)
•
TAL (acts on this site to block water reabsorption)
Leaving the freeway means reabsorption
Entering the freeway means secretion
17
Acids must be buffered, transported away from cells,
and eliminated from the body.
These are the most important buffers.
Phosphate: important renal tubular buffer
HPO4- + H+
H2PO4
Ammonia: important renal tubular buffer
NH3 + H+
NH4+
Proteins: important intracellular and plasma buffers
H+ + Hb
HHb
Bicarbonate: most important Extracellular buffer and
is also another important renal tubular buffer.
H2O + CO2
H2CO3
H+ + HCO3 -
Buffering Systems
• The three different buffering systems are:
1) Respiratory buffering system
• Uses bicarbonate
2) Blood buffering system
• Uses bicarbonate, phosphate, and protein
3) Renal buffering system
• Uses bicarbonate, phosphate, and ammonia
BUFFERING SYSTEMS
BUFFERS USED BY THE BUFFERING SYSTEMS
Bicarbonate
Respiratory System
Proteins
Bicarbonate
Phosphate
Blood
Bicarbonate
Kidneys
Phosphate
Ammonia
pH Imbalances
• Acidosis
–Can be metabolic or respiratory
• Alkalosis
–Can be metabolic or respiratory
Acidosis
• Acidosis is excessive blood acidity caused by
an overabundance of acid in the blood or a
loss of bicarbonate from the blood (metabolic
acidosis), or by a buildup of carbon dioxide in
the blood that results from poor lung function
or slow breathing (respiratory acidosis).
Respiratory acidosis
• Respiratory acidosis is due to an accumulation
of CO2 in the blood stream. This pushes the
carbonic anhydrase reaction to the right,
generating H+:
carbonic anhydrase
H2O + CO2
H2CO3
HCO3(-) + H+
Respiratory acidosis
• Cause
• The increase in CO2 in the blood is often caused by
hypoventilation.
• This can be caused by asthma, COPD, and overuse of
sedatives, barbiturates, or narcotics such as valium, heroin, or
other drugs which make you sleepy.
• It can also be caused by other things wrong with the lungs: an
accident were the breathing muscles are damaged (causing
decreased ventilation), airway obstruction, or lung disease
(pneumonia, cystic fibrosis, emphysema, etc.).
Respiratory acidosis
• Compensation
• Even if the peripheral receptors sense the change in pH, the
lungs are unresponsive.
• The kidneys will compensate by secreting H+.
• If H+ excretion cannot restore the balance, the kidneys will
also generate bicarbonate.
• Since the primary abnormality is an increase in pCO2, the
compensatory response is intracellular buffering of hydrogen
(by hemoglobin) and renal retention of bicarbonate, which
takes several days to occur.
Respiratory acidosis
• Symptoms
• May have no symptoms but usually experience headache,
nausea, vomiting, and fatigue.
• Breathing becomes deeper and slightly faster (as the body
tries to correct the acidosis by expelling more carbon dioxide).
• As the acidosis worsens, people begin to feel extremely weak
and drowsy and may feel confused and increasingly
nauseated.
• Eventually, blood pressure can fall, leading to shock, coma,
and death.
• The most common clinical intervention is IV sodium
bicarbonate and applying an oxygen mask.
Respiratory acidosis
• Treatment
• Treatment is aimed at the underlying disease, and
may include:
• Bronchodilator drugs to reverse some types of
airway obstruction
• Noninvasive positive-pressure ventilation
(sometimes called CPAP or BiPAP) or a breathing
machine, if needed
• Oxygen if the blood oxygen level is low
• Treatment to stop smoking
Metabolic acidosis
• Metabolic acidosis is the gain of acid or the loss of
bicarbonate.
• Cause
• Usual causes are the generation of ketone bodies in
uncontrolled diabetes mellitus, diarrhea (loss of bicarbonate),
excess protein consumption (breakdown products are amino
ACIDS), or excess alcohol consumption:
(alcohol
formaldehyde
acetic acid).
• Can also be caused by ingestion of an acid (aspirin, ethanol, or
antifreeze).
• Exercise creates a milder, transient metabolic acidosis because
of the production of lactic acid.
Metabolic acidosis
• Compensation
• The body will compensate with hyperventilation and
increased bicarbonate reabsorption in the kidney.
• Since the primary abnormality is a decrease in HCO3, the
compensatory response includes extracellular buffering (by
bicarbonate), intracellular buffering (by phosphate and
proteins), respiratory compensation and renal hydrogen
excretion.
• Metabolic acidosis stimulates an increase in ventilation
(reducing pCO2).
• This hyperventilation is called Kussmaul's respiration.
Metabolic acidosis
• Symptoms
• Most symptoms are caused by the underlying
disease or condition that is causing the metabolic
acidosis.
• Metabolic acidosis itself usually causes rapid
breathing.
• Confusion or lethargy may also occur.
• Severe metabolic acidosis can lead to shock or death.
• In some situations, metabolic acidosis can be a mild,
chronic (ongoing) condition.
Metabolic acidosis
• Treatment is give i.v. of sodium bicarbonate.
• The HCO3- deficit can be calculated by using the following
equation:
• HCO3- deficit = deficit/L (desired serum HCO3- - measured
HCO3-) x 0.5 x body weight (volume of distribution for
HCO3-)
• This provides a crude estimate of the amount of HCO3that must be administered to correct the metabolic
acidosis; the serum HCO3- level or pH should be
reassessed frequently.
Alkalosis
• Alkalosis is excessive blood alkalinity caused
by an overabundance of bicarbonate in the
blood or a loss of acid from the blood
(metabolic alkalosis), or by a low level of
carbon dioxide in the blood that results from
rapid or deep breathing (respiratory alkalosis).
Respiratory alkalosis
• Respiratory alkalosis is generally caused by hyperventilation,
usually due to anxiety. The primary abnormality is a
decreased pCO2.
• Cause
• Caused from a decrease in CO2 in the blood because the lungs
are hyperventilating (anxiety, but not panting).
• Fever or aspirin toxicity may also cause respiratory alkalosis.
Respiratory alkalosis
• Compensation
• The body will reduce the breathing rate if the
respiratory problem is from anxiety.
• The kidney will excrete bicarbonate.
• The kidney will also stop excreting H+, and
may also reabsorb more H+.
Respiratory alkalosis
• Compensation
• The compensatory response to a respiratory alkalosis is
initially a release of hydrogen from extracellular and
intracellular buffers.
• This is followed by reduced hydrogen excretion by the
kidneys.
• This results in decreased plasma bicarbonates.
• In chronic respiratory alkalosis, compensatory measures can
make the pH revert to normal.
Respiratory alkalosis
•
•
•
•
Symptoms
Irritability
Muscle twitching
Muscle cramps
Respiratory alkalosis
• Treatment
• Treatment for hyperventilation is to breathe into a
paper bag for a while, as the person breathes carbon
dioxide back in after breathing it out.
• For severe cases, need to replace the water and
electrolytes (sodium and potassium).
Metabolic alkalosis
• Metabolic alkalosis is due to the gain of base or the
loss of acid. The primary abnormality is having an
increased HCO3 seen in the blood test.
• Cause
• Caused from an increase in bicarbonate in the
blood because of ingestion of excess bicarbonate
in the form of an antacid (Tums), eating excess
fruits (vegetarian diets and fad diets*), loss of
acid from vomiting, or loss of potassium from
diuretics.
Metabolic alkalosis
• Compensation
• This is initially buffered by hydrogen buffers (such as plasma
proteins and lactate).
• Chemoreceptors in the respiratory center sense the alkalosis
and trigger hypoventilation, resulting in increased pCO2.
• The respiratory system will hypoventilate but this will not be
effective because CO2 will accumulate and the CO2 receptors
will override the pH receptors.
Metabolic alkalosis
• Compensation
• Naturally, the extent of respiratory compensation will be
limited by the development of hypoxia with continued
hypoventilation. The kidney will make more of a difference by
not reabsorbing bicarbonate.
• In addition to respiratory compensation, the kidneys excrete
the excess bicarbonate. However, this takes several days to
occur.
Metabolic alkalosis
•
•
•
•
•
•
•
•
Symptoms
Confusion (can progress to stupor or coma)
Hand tremor
Light-headedness
Muscle twitching
Nausea, vomiting
Numbness or tingling in the face, hands, or feet
Prolonged muscle spasms (tetany)
Metabolic alkalosis
• Treatment is to give an anti-emetic if the problem is from
vomiting. If not, give an i.v. of normal saline to increase the
blood volume.
• If potassium is also low, would have to add that to the i.v.
Interpreting Arterial Blood Gases
(ABG)
• This blood test is from arterial blood, usually from the radial
artery.
• There are three critical questions to keep in mind when
attempting to interpret arterial blood gases (ABGs).
First Question: Does the patient exhibit acidosis or alkalosis?
Second Question: What is the primary problem? Metabolic?
or Respiratory?
Third Question: Is the patient exhibiting a compensatory
state?
Assessment Step 1
• Step One: Determine the acid/base status of the arterial
blood.
• If the blood's pH is less than 7.35 this is an acidosis, and if it is
greater than 7.45 this is an alkalosis.
You may hear nurses or doctors say: "The patient is 'acidotic'
or 'alkalotic'
• If pH is normal, use the patient history to determine if it is
respiratory or metabolic. To figure out if it is alkalosis or
acidosis, check the table.
Know the normal ranges for pH
ACID BASE PARAMETERS
(The problem chemical is in yellow)
Respiratory
Acidosis
PH
Respiratory
Alkalosis
PH
PCO2
HCO3
If compensating
Or normal if not compensating
PCO2
HCO3
If compensating
Or normal if not compensating
Metabolic
Acidosis
PH
Metabolic
Alkalosis
PH
PCO2
HCO3
If compensating
Or normal if not compensating
PCO2
If compensating
Or normal if not compensating
HCO3
Assessment Step 2
• Once you have determined the pH, you can move on to
determine which system is the 'primary' problem:
respiratory or metabolic.
• To do this, examine the pCO2 and HCO3 levels.
• If only the pCO2 is abnormal, it is a respiratory
problem.
• If only the HCO3 is abnormal, it is a metabolic problem.
• If both are abnormal, they are either both high or both
low. That means they are compensating. One will never
be high and the other low. Check the table to see if it is
respiratory or metabolic.
Assessment Step 3
• Determine if the body is attempting to
compensate for the imbalance or not.
• If they are compensating, both CO2 and HCO3
will be high, or both will be low. To know if
they have fully compensated, see if pH has
returned to normal or not.
Review the three essential steps of
ABG analysis
• Number One:
Determine if the patient is demonstrating an acidotic (remember: pH less
than 7.35) or alkalotic (pH greater than 7.45).
• Number Two:
• What is the 'primary problem?
• If the patient is acidotic with a pC02 greater than 45 mmHg it is RESPIRATORY
• If the patient is alkalotic with a pC02 less than 35 mmHg it is RESPIRATORY
• If the patient is acidotic with a HC03 less than 22 mEq/L it is METABOLIC
• If the patient is alkalotic with a HC03 greater than 26 mEq/L it is METABOLIC
Know the normal ranges for pCO2 and HCO3
Review the three essential steps of
ABG analysis
• Number Three:
Is the patient compensating?
• Are both components (HCO3 and pCO2) shifting in the
same direction?
• Up or down the continuum?
• Above or below the normal ranges?
• If this is noted, you know that the patient’s buffering
systems are functioning and are trying to bring the acidbase balance back to normal.
http://www.wikihow.com/Interpret-Blood-Gas-Results
Arterial Blood Gas problems when
compensation is present
pH
Respiratory
Acidosis
Acid
Metabolic
Alkalosis
Base
Metabolic
Acidosis
Acid
Respiratory
Alkalosis
Base
PCO2
HCO3
59
Condition
pH
Resp
CO2
Bicarb
Compensating?
Resp acidosis
Low
Hypoventilating
High
High
Yes
Resp acidosis
Low
Hypoventilating
High
Norm
No
Resp alkalosis
High
Hyperventilating
Low
Low
Yes
Resp alkalosis
High
Hyperventilating
Low
Norm
No
Metab acidosis
Low
Normal
Low
Low
Yes
Metab acidosis
Low
Normal
High
Norm
No
Metab Alkalosis
High
Normal
High
high
Yes
Metab Alkalosis
High
Normal
Low
Norm
No
Kussmaul Breathing
• Kussmaul breathing is a form of
hyperventilation often associated with severe
metabolic acidosis, particularly diabetic
ketoacidosis (DKA) but also renal failure.
Case Study 1
A patient recovering from surgery in the post-anesthesia care unit is
difficult to arouse two hours following surgery. The nurse in the PACU
has been administering Morphine Sulfate intravenously to the patient for
complaints of post-surgical pain. The patient’s respiratory rate is 7 per
minute and demonstrates shallow breathing. The patient does not
respond to any stimuli! The nurse assesses the ABCs (remember Airway,
Breathing, Circulation!) and obtains ABGs STAT! The STAT results
come back from the laboratory and show:
pH = 7.15 (low)
C02 = 68 mmHg (high)
HC03 = 22 mEq/L (normal)
1.
2.
3.
4.
Compensated Respiratory Acidosis
Uncompensated Metabolic Acidosis
Compensated Metabolic Alkalosis
Uncompensated Respiratory Acidosis
Answer
• The answer is #4
uncompensated respiratory acidosis
Case Study 2
•
An infant, three weeks old, is admitted to the Emergency Room. The
mother reports that the infant has been irritable, difficult to
breastfeed and has had diarrhea for the past 4 days. The infant’s
respiratory rate is elevated and the fontanels are sunken. The
Emergency Room physician orders ABGs after assessing the ABCs.
•
The results from the ABGs come back from the laboratory and show:
pH = 7.37 (normal)
C02 = 29 mmHg (low)
HC03 = 17 mEq/L (low)
1.
2.
3
4
Compensated Respiratory Alkalosis
Uncompensated Metabolic Acidosis
Compensated Metabolic Acidosis
Uncompensated Respiratory Acidosis
Answer
• Answer is #3
• Compensated Metabolic Acidosis
Case Study 3
•
•
1.
2.
3.
4.
A patient, 5 days post-abdominal surgery, has a nasogastric tube. The
nurse notes that the nasogastric tube (NGT) is draining a large amount
(900 cc in 2 hours) of coffee ground secretions. The patient is not
oriented to person, place, or time. The nurse contacts the attending
physician and STAT ABGs are ordered.
The results from the ABGs come back from the laboratory and show:
pH = 7.52 (high)
C02 = 35 mmHg (normal)
HC03 = 29 mEq/L (high)
Compensated Respiratory Alkalosis
Uncompensated Metabolic Acidosis
Compensated Metabolic Acidosis
Uncompensated Metabolic Alkalosis
Answer
•
•
Answer is #4
Uncompensated Metabolic Alkalosis
Case Study 4
•
A patient is admitted to the hospital and is being prepared for a
craniotomy (brain surgery). The patient is very anxious and scared of
the impending surgery. He begins to hyperventilate and becomes very
dizzy. The patient looses consciousness and the STAT ABGs reveal:
•
•
•
•
The results from the ABGs come back from the laboratory and show:
pH = 7.57 (high)
C02 = 26 mmHg (low)
HC03 = 24 mEq/L (normal)
1.
2.
3.
4.
Compensated Metabolic Acidosis
Uncompensated Metabolic Acidosis
Uncompensated Respiratory Alkalosis
Uncompensated Respiratory Acidosis
Answer
•
•
The answer is #3
Uncompensated Respiratory Alkalosis
Case Study 5
•
A two-year-old is admitted to the hospital with a diagnosis of asthma
and respiratory distress syndrome. The father of the infant reports to
the nurse that he has observed slight tremors and behavioral changes
in his child over the past three days. The attending physician orders
routine ABGs following an assessment of the ABCs. The ABG results
are:
•
•
•
pH = 7.36 (normal)
C02 = 69 mmHg (high)
HC03 = 36 mEq/L (high)
1.
2.
3.
4.
Compensated Respiratory Alkalosis
Uncompensated Metabolic Acidosis
Compensated Respiratory Acidosis
Uncompensated Respiratory Alkalosis
Answer
• Answer is #3
• Compensated Respiratory Acidosis
Case Study 6
•
•
1.
2.
3.
4.
A young woman, drinking beer at a party, falls and hits
her head on the ground. A friend dials "911" because
the young woman is unconscious, depressed ventilation
(shallow and slow respirations), rapid heart rate, and is
profusely bleeding from both ears.
Which primary acid-base imbalance is this young
woman at risk for if medical attention is not provided?
metabolic acidosis
metabolic alkalosis
respiratory acidosis
respiratory alkalosis
Answer
• Correct answer is #3
• Respiratory Acidosis
Case Study 7
•
•
1.
2.
3.
4.
An 11-year old boy is admitted to the hospital with
vomiting (losing acid!), nausea and overall weakness. The
nurse notes the laboratory results: potassium: 2.9 mEq
(low).
Which primary acid-base imbalance is this boy at risk for
if medical attention is not provided? Note: Potassium
makes blood more acidic.
metabolic acidosis
metabolic alkalosis
respiratory acidosis
respiratory alkalosis
Answer
• Correct Answer is #2
• Metabolic Alkalosis
Case Study 8
• An elderly gentleman is seen in the emergency department at
a community hospital. He admits to taking many tablets of
aspirin (salicylates) over the last 24-hour period because of a
severe headache. He complains of an inability to urinate. His
vital signs are: Temp = 98.5; apical pulse = 92; respiration = 30
and deep.
• Which primary acid-base imbalance is the gentleman at risk
for if medical attention is not provided?
1.
2.
3.
4.
metabolic acidosis
metabolic alkalosis
respiratory acidosis
respiratory alkalosis
Answer
• Correct Answer is #1
• Metabolic Acidosis
Case Study 9
•
•
1.
2.
3.
4.
A young man is found at the scene of an automobile accident in a
state of emotional distress. He tells the paramedics that he feels
dizzy, tingling in his fingertips, and does not remember what
happened to his car. Respiratory rate is rapid at 34/minute.
Which primary acid-base disturbance is the young man at risk for if
medical attention is not provided?
metabolic acidosis
metabolic alkalosis
respiratory acidosis
respiratory alkalosis
Answer
• Correct Answer is #4
• Respiratory Alkalosis
Case Study 10
12 year old diabetic presents with Kussmaul breathing
•
•
•
•
pH :
7.05 (low)
pCO2: 12 mmHg (very low)
pO2:
108 mmHg (normal)
HCO3: 5 mEq/L (low)
– What is the diagnosis? Is he compensating? What
caused the problem?
Answer
12 year old diabetic presents with Kussmaul breathing
•
•
•
•
pH :
7.05 (low)
pCO2: 12 mmHg (very low)
pO2:
108 mmHg (normal)
HCO3: 5 mEq/L (low)
– Compensating metabolic acidosis without
hypoxemia due to ketoacidosis
Case Study 11
17 year old w/severe kyphoscoliosis, admitted for pneumonia.
Elevated respiratory rate.
•
•
•
•
pH:
pCO2:
pO2:
HCO3:
7.37 (normal)
25 mmHg (low)
60 mmHg (low)
14 mEq/L (low)
– What is the diagnosis? Is he compensating? What
caused the problem?
Case Study 11
17 year old w/severe kyphoscoliosis, admitted for pneumonia.
Elevated respiratory rate.
•
•
•
•
pH:
pCO2:
pO2:
HCO3:
7.37 (normal)
25 mmHg (low)
60 mmHg (low)
14 mEq/L (low)
– Compensated respiratory alkalosis due to chronic
hyperventilation secondary to hypoxia
Case Study 12
9 year old w/hx of asthma, audibly wheezing x 1 week, has
not slept in 2 nights; presents sitting up and using accessory
muscles to breathe w/audible wheezes
•
•
•
•
pH:
pCO2:
pO2
HCO3:
7.51 (high)
25 mmHg (low)
35 mmHg (very low)
22 mEq/L (normal)
– What is the diagnosis? Is he compensating? What
caused the problem?
Case Study 12
9 year old w/hx of asthma, audibly wheezing x 1 week, has
not slept in 2 nights; presents sitting up and using accessory
muscles to breathe w/audible wheezes
•
•
•
•
pH:
pCO2:
pO2
HCO3:
7.51 (high)
25 mmHg (low)
35 mmHg (very low)
22 mEq/L (normal)
– Uncompensated respiratory alkalosis with severe
hypoxia due to asthma exacerbation
Case Study 13
7 year old post-op presenting with chills, fever and hypotension
•
•
•
•
pH:
pCO2:
pO2:
HCO3:
7.25 (low)
36 mmHg (low)
55 mmHg (low)
10 mEq/L (low)
– What is the diagnosis? Is he compensating? What
caused the problem?
Case Study 13
7 year old post-op presenting with chills, fever and hypotension
•
•
•
•
pH:
pCO2:
pO2:
HCO3:
7.25 (low)
36 mmHg (normal)
55 mmHg (low)
10 mEq/L (low)
– Uncompensated metabolic acidosis due to low
perfusion state and hypoxia causing increased
lactic acid
Urinalysis Lab
•
1. What would most likely be the cause of a urine sample with a positive test for
nitrites, leukocytes and a slightly higher than normal pH? Urinary tract infection
•
2. Are proteins or blood normally found in urine? If they are present, how might
they get there? No; kidney infection, glomerulonephritis, trauma, kidney stones
•
3. If the urine sample tests positive for ketones and glucose, for what disease
should the patient be checked? Diabetes mellitus
•
4. Elevated levels of urobilinogen and bilirubin may indicate problems with what
organ?
Liver
•
•
5. What dietary habits may cause an acidic urine sample (more acidic than
normal)? High proteins or acidic foods
•
6. What would cause a basic urine sample? vegetarian diet
Urinalysis Lab
7. Normal urine is usually yellow to amber in color, due to the presence of what
pigment? Urochrome
8. What blood protein (like all other proteins) is too large to pass through the
glomerular filtration membrane, and so is not normally found in the urine? Albumin
9. Circle the correct term: Hematuria / Ketonuria, the appearance of red blood cells in
the urine, indicates pathology.
10. The appearance of bile pigments in the urine is known as __________________,
and indicates liver disease.
Bilirubinuria
11. Circle the correct term: Casts / Caliculi are hardened cell fragments formed in the
DCT and collecting ducts and flushed out of the urinary tract.
12. When determining the presence of inorganic constituents such as sulfates,
phosphates, and chlorides, you look for the formation of a precipitate. What is a
precipitate? A cloudy solid that forms
Urinalysis