Download acid base self study with practice questions

Study Guide NURS 2140
Chapter 19 – Acid Base Review Practice Questions
Interpreting Arterial Blood Gas Self Study: (condensed from the self study packet offered at
Orlando Regional Healthcare, Education & Development, copyright 2004)
“Arterial blood gas analysis is an essential part of diagnosing and managing a patient’s
Oxygenation status and acid-base balance. The usefulness of this diagnostic tool is dependent
on being able to correctly interpret the results. This self-learning packet will examine the
components of an arterial blood gas, what each component represents and the interpretation of
these values to determine the patient’s condition and treatment.”
The Basics explained:
The pH is a measurement of the acidity or alkalinity of the blood. It is inversely proportional to
the number of hydrogen ions (H+) in the blood. The more H+ present, the lower the pH will be.
Likewise, the fewer H+ present, the higher the pH will be. The pH of a solution is measured on
a scale from 1 (very acidic) to 14 (very alkalotic). A liquid with a pH of 7, such as water, is
neutral (neither acidic nor alkalotic).
1
Very Acidic
7
Neutral
14
Very Alkalotic (Base)
The normal blood pH range is 7.35 to 7.45. In order for normal metabolism to take place, the
body must maintain this narrow range at all times. When the pH is below 7.35, the blood is said
to be acidic. Changes in body system functions that occur in an acidic state include a decrease
in the force of cardiac contractions, a decrease in the vascular response to catecholamines, and
a diminished response to the effects and actions of certain medications. When the pH is above
7.45, the blood is said to be alkalotic. An alkalotic state interferes with tissue oxygenation and
normal neurological and muscular functioning. Significant changes in the blood pH above 7.8
or below 6.8 will interfere with cellular functioning, and if uncorrected, will lead to death.
Key Concepts:
 The only 2 ways an acidotic state can exist is from either too much PaCO2 or too little HCO3.
 The only 2 ways an alkalotic state can exist is from either too little PaCO2 or too much HCO3.
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The body regulates acid base in order to maintain normal pH (7.35-7.45) by using delicate buffer
mechanisms between the respiratory and renal systems.
The Respiratory (Lungs) Buffer Response
A normal by-product of cellular metabolism is carbon dioxide (CO2). CO2 is carried in the
blood to the lungs, where excess CO2 combines with water (H2O) to form carbonic acid
(H2CO3). The blood pH will change according to the level of carbonic acid present. This
triggers the lungs to either increase or decrease the rate and depth of ventilation until the
appropriate amount of CO2 has been re-established. Activation of the lungs to compensate for
an imbalance starts to occur within 1 to 3 minutes.
The Renal (Metabolic) Buffer Response
In an effort to maintain the pH of the blood within its normal range, the kidneys excrete or
retain bicarbonate (HCO3-). As the blood pH decreases, the kidneys will compensate by
retaining HCO3- and as the pH rises, the kidneys excrete HCO3- through the urine. Although the
kidneys provide an excellent means of regulating acid-base balance, the system may take from
hours to days to correct the imbalance. When the respiratory and renal systems are working
together, they are able to keep the blood pH balanced by maintaining 1 part acid to 20 parts
base.
ACID BASE DISORDERS
Respiratory Acidosis
Respiratory acidosis is defined as a pH less than 7.35 with a PaCO2 greater than 45 mm Hg.
Acidosis is caused by an accumulation of CO2 which combines with water in the body to
produce carbonic acid, thus, lowering the pH of the blood. Any condition that results in
hypoventilation can cause respiratory acidosis. These conditions include:
Central nervous system depression related to head injury
Central nervous system depression related to medications such as narcotics, sedatives,
or anesthesia
Impaired respiratory muscle function related to spinal cord injury, neuromuscular
diseases, or neuromuscular blocking drugs
Pulmonary disorders such as atelectasis, pneumonia, pneumothorax, pulmonary
edema, or bronchial obstruction
Massive pulmonary embolus
Hypoventilation due to pain, chest wall injury/deformity, or abdominal distension.
SIGNS AND SYMPTOMS OF RESPIRATORY ACIDOSIS
Dyspnea
Respiratory distress
Shallow and/or slow respirations
Cardiovascular
Tachycardia
Dysrhythmias
Neurological
Headache
Restlessness
Confusion
Pulmonary
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CLINICAL APPLICATION:
If the CO2 becomes extremely high, drowsiness and unresponsiveness may be noted.
Increasing ventilation (minute volume) will correct respiratory acidosis. The method for
achieving this will vary with the cause of hypoventilation. If the patient is unstable, manual
ventilation with a bag mask (ambu bag) is indicated until the underlying problem can be
addressed. After stabilization, rapidly resolvable causes are addressed immediately. Causes that
can be treated rapidly include pneumothorax, pain, and CNS depression related to medications
(i.e.: narcotic overdose-narcan). If the cause cannot be readily resolved, the patient may require
mechanical ventilation while treatment is rendered. Although patients with hypoventilation often
require supplemental oxygen, it is important to remember that oxygen alone will not correct the
problem.
Respiratory Alkalosis
Respiratory alkalosis is defined as a pH greater than 7.45 with a PaCO2 less than 35 mm Hg.
Any condition that causes hyperventilation can result in respiratory alkalosis. These conditions
include:
Psychological responses, such as anxiety or fear
Pain
Increased metabolic demands, such as fever, sepsis, pregnancy, or thyrotoxicosis
(condition caused by overactive thyroid)
Medications, such as respiratory stimulants
Central nervous system lesions (abnormality in CNS caused by disease or trauma)
SIGNS AND SYMPTOMS OF RESPIRATORY ALKALOSIS
Cardiovascular
Dysrhythmias
Palpitations
Diaphoresis
Neurological
Light-headedness
Numbness and tingling
Confusion
Inability to concentrate
Blurred vision
Miscellaneous
Dry mouth
Tetanic spasms of the arms and legs
CLINICAL APPLICATION:
Treatment of respiratory alkalosis centers on resolving the underlying problem.
Patients presenting with respiratory alkalosis have dramatically increased work of
breathing and must be monitored closely for respiratory muscle fatigue. When the
respiratory muscles become exhausted, acute respiratory failure may ensue.
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Metabolic Acidosis
Metabolic acidosis is defined as a bicarbonate level of less than 22 mEq/L with a pH of less
than 7.35. Metabolic acidosis is caused by either a deficit of base in the bloodstream or an
excess of acids, other than CO2. Diarrhea and intestinal fistulas may cause decreased levels of
base. Causes of increased acids include:
Renal failure
Diabetic ketoacidosis
Anaerobic metabolism
Starvation
Salicylate (aspirin) intoxication
SIGNS AND SYMPTOMS OF METALBOLIC ACIDOSIS
Pulmonary
Kussmaul’s respirations (deep and labored breathing)
Cardiovascular
Dysrhythmias
Warm, flushed skin
Neurological
Headache
Confusion
Restlessness
Lethargy
Stupor or coma
Gastrointestinal
Nausea and vomiting
As with most acid-base imbalances, the treatment of metabolic acidosis is dependent upon the
cause. The presence of metabolic acidosis should spur a search for hypoxic tissue somewhere
in the body. Hypoxemia can lead to anaerobic metabolism system-wide, but hypoxia of any
tissue bed (brain, heart, kidneys, liver, pancreas, etc.) will produce metabolic acids as a result of
anaerobic metabolism even if the PaO2 is normal. The only appropriate way to treat this source of
acidosis is to restore tissue perfusion to the hypoxic tissues. Other causes of metabolic acidosis
should be considered after the possibility of tissue hypoxia has been addressed.
CLINICAL APPLICATION:
Current research has shown that the use of sodium bicarbonate is indicated only for known
bicarbonate-responsive acidosis, such as that seen with renal failure. Routine use of sodium
bicarbonate to treat metabolic acidosis results in subsequent metabolic alkalosis with
hypernatremia and should be avoided.
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Metabolic Alkalosis
Metabolic alkalosis is defined as a bicarbonate level greater than 26 mEq/liter with a pH greater
than 7.45. Either an excess of base or a loss of acid within the body can cause metabolic
alkalosis. Excess base occurs from








ingestion of antacids
excessive use of bicarbonate
use of lactate in dialysis
vomiting
gastric suction
hypochloremia (low chloride)
excess administration of diuretics
high levels of aldosterone
SIGNS AND SYMPTOMS OF METALBOLIC ALKALOSIS
Pulmonary
Respiratory depression
Musculoskeletal
Weakness
Muscle twitching
Muscle cramps
Tetany
Neurological
Dizziness
Lethargy
Disorientation
Seizures
Coma
Gastrointestinal
Nausea
Vomiting
Metabolic alkalosis is one of the most difficult acid-base imbalances to treat. Bicarbonate
excretion through the kidneys can be stimulated with drugs such as acetazolamide (Diamox®),
but resolution of the imbalance will be slow. In severe cases, IV administration of acids may
be used.
CLINICAL APPLICATION:
It is significant to note that metabolic alkalosis in hospitalized patients is usually
iatrogenic (brought on about unintentionally by treatment of other medical conditions).
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COMPONENTS OF THE ARTERIAL BLOOD GAS
The arterial blood gas provides the following values:
pH:
Measurement of acidity or alkalinity, based on the hydrogen (H+) ions present.
The normal range is 7.35 to 7.45
Remember:
pH > 7.45 = alkalosis
pH< 7.35 = acidosis
PaO2:
The partial pressure of oxygen that is dissolved in arterial blood.
The normal range is 80 to 100 mm Hg.
SaO2:
The arterial oxygen saturation.
The normal range is 95% to 100%.
PaCO2:
The amount of carbon dioxide dissolved in arterial blood.
The normal range is 35 to 45 mm Hg.
Remember:
pCO2 >45 = acidosis
pCO2 <35 = alkalosis
HCO3
The calculated value of the amount of bicarbonate in the bloodstream.
The normal range is 22 to 26 mEq/liter
Remember:
HCO3 > 26 = alkalosis
HCO3 < 22 = acidosis
B.E.
The base excess indicates the amount of excess or insufficient level of bicarbonate in the
system.
The normal range is -2 to +2 mEq/liter. (-3 to +3 in Osborn book)
Remember:
A negative base excess indicates a base deficit in the blood.
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THE 6 EASY STEPS TO ARTERIAL BLOOD GAS (ABG) INTREPRETATION: (condensed
from www.ED4NURSES.com, copyright 1997-2012, ED4Nurses, Inc.)
The 6 Easy Steps to ABGAnalysis:
Step 1: Analyze the pH
The first step in analyzing ABGs is to look at the pH. Normal blood pH is
7.4, plus or minus 0.05, forming the range 7.35 to 7.45. If blood pH falls below 7.35 it is acidic.
If blood pH rises above 7.45, it is alkalotic. If it falls into the normal range, note what side of 7.4
it falls on. Lower than 7.4 is normal/acidic, higher than 7.4 is normal/alkalotic.
Step2: Analyze the CO2
The second step is to examine the pCO2. Normal pCO2 levels are 35 ‐ 45mmHg. Below 35 is
alkalotic, above 45 is acidic.
Step 3: Analyze the HCO3
The third step is to look at the HCO3 level. A normal HCO3 level is 22--‐26 mEq/L. If the
HCO3 is below 22, the patient is acidotic. If the HCO3 is above 26, the patient is alkalotic.
Step 4: Match the CO2 or the HCO3 with the pH
Next match either the pCO2 or the HCO3 with the pH to determine the acid--‐base disorder. For
example, if the pH is acidotic, and the CO2 is acidotic, then the acid--‐base disturbance is being
caused by the respiratory system. Therefore, we call it a respiratory acidosis. However, if the pH
is alkalotic and the HCO3 is alkalotic, the acid--‐base disturbance is being caused by the
metabolic (or renal) system. Therefore, it will be a metabolic alkalosis.
Step 5: Does the CO2 or HCO3 go the opposite direction of the pH?
Fifth, does either the CO2 or HCO3 go in the opposite direction of the pH? If so, there is
compensation by that system. For example, the pH is acidotic, the CO2 is acidotic, and the
HCO3 is alkalotic. The CO2 matches the pH making the primary acid--‐base disorder respiratory
acidosis. The HCO3 is opposite of the pH and would be evidence of compensation from the
metabolic system. (explained more in next section).
Step 6: Analyze the pO2 and the O2 saturation.
Finally, evaluate the PaO2 and O2 sat. If they are below normal there is evidence of hypoxemia.
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ABG Test
pH
PaCO2
HCO3
PaO2 (dissolved O2)
SaO2 (saturation)
Normal Range
7.35 – 7.45
34 – 45
22-26
80-100
95-100%
Decreased Value
Acidosis
Alkalosis
Acidosis
Hypoxemia
Hypoxemia
Increased Value
Alkalosis
Acidosis
Alkalosis
O2 Therapy
----------------------
Notice that if the pH is lower than 7.35 it indicates acidosis, if the pH is higher than 7.45 it
indicates alkalosis. The HCO3 is also acidotic if it is low: less than 22 indicate acidosis. If the
HCO3 is higher than 26 it indicates alkalosis. However, if the CO2 is lower than 35 it indicates
alkalosis, and if the CO2 is higher than 45 It indicates acidosis. One way to remember this
relationship is to use the acronym. ROME.
Respiratory
Opposite
Metabolic
Equal
The PaCO2 is the respiratory component of the ABG, and if it is low and the pH is high the
patient would have a respiratory alkalosis. They move in opposite directions to match.
The HCO3 is the metabolic component of the ABG. If the HCO3 is low and the pH is low the
patient would have metabolic acidosis. They move in the same direction to match.
STEP 5 REFERS TO COMPENSATION.
Compensation is the attempt by the body to maintain homeostasis by correcting the pH. The
opposite system will do this. The component of the respiratory system that balances the pH is the
dissolved carbon dioxide (PaCO2) that is produced by the cellular processes and removed by the
lungs. The component of the renal system that balances the pH is the dissolved bicarbonate
(HCO3) produced by the kidneys. The kidneys also help control pH by eliminating hydrogen
(H+) ions. The way the two systems interact is through the formation of carbonic acid (H2CO3).
Movement through the carbonic acid system is fluid and constant. What this means is that water
(H2O) can combine with CO2 and form carbonic acid. If necessary, carbonic acid (H2CO3) can
then break up to form hydrogen ions (H+) and bicarbonate (HCO3). This system works in both
directions. By balancing back and forth, a normal pH is achieved. The respiratory system
balances the pH by increasing or decreasing the respiratory rate, thereby manipulating the
PaCO2 level. Fast and deep breathing (Increased minute volume) “blows off” PaCO2.
Conversely, slow and shallow breathing (decreased minute volume) “retains” PaCO2. The renal
system balances pH by producing HCO3 or by eliminating hydrogen ions (H+). The renal system
will reflect changes in metabolic activity within the body. For example, a patient in shock will
undergo anaerobic metabolism, which produces lactic acid. The production of lactic acid will
bind or use up available HCO3 and will be manifested by a decrease in the HCO3 level.
Therefore, the HCO3 level is an indicator of metabolic acid-base balance.
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Balance must always be achieved by the opposing system. Therefore, our body regulates pH by
using the opposing system to balance pH. So if the pH is out of balance because of a respiratory
disorder, it will be the renal system that makes the corrections to balance the pH. Conversely, if
the renal system is to blame for the pH disorder, the respiratory system will have to compensate.
This process is called compensation. Compensation may not always be complete.
Complete or Full compensation returns the pH balance to normal. There are times when the
imbalance is too large for compensation to restore the pH to normal. This is called partial
compensation. Like the seesaw, compensation must come from the opposite system.
Step 5 analyzes compensation by looking for the system that is going the opposite direction of
the pH. Opposite in terms of acidosis and alkalosis. (i.e.: pH is acid (low), HCO3 is acid (low)
but PaCO2 is alkalotic (high) – would be Metabolic Acidosis with partial compensation from the
respiratory system).
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Examples of interpretation ABG are using the six steps:
Example 1:
pH
7.27
acidotic
PaCO2
53
acidotic
PaO2
50
low
SaO2
79%
low
HCO3
24
normal
Step 1: The pH is less than 7.35, so it is acidotic.
Step 2: The CO2 is greater than 45, so it is acidotic.
Step 3: The HCO3 is normal.
Step 4: The PaCO2 matches the pH, because they are both acidotic. Therefore the imbalance is
respiratory acidosis. It is acidotic because the pH is acidotic, it is respiratory because the PaCO2
moved opposite (ROME) and matches the pH.
Step 5: The HCO3 is normal, therefore no compensation. If the HCO3 was alkalotic (high)
(moved in opposite direction to pH) then a compensation (partial) would be present.
Step 6: Lastly, the PaO2 and SaO2 are both low indicating hypoxemia.
The Full Interpretation for this ABG is: Uncompensated Respiratory Acidosis with
hypoxemia.
This patient has an acute respiratory disorder. Caused by hypoventilation. Retaining CO2.
Hypoventilation is slow shallow breathing (decreased Minute Volume) and decreased Alveolar
Minute Volume (areas that actually participate in gas exchange in the lungs). These conditions
are: COPD, Drug overdoses (narcotics, opiates), obstructed airway, neuromuscular diseases that
affect breathing, chest trauma, high spinal column injuries and pulmonary edema.
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Example 2:
pH
7.52
alkalotic
PaCO2
29
alkalotic
PaO2
100
normal
SaO2
98%
normal
HCO3
23
normal
Step 1: The pH is greater than 7.45, so it is alkalotic
Step 2: The PaCO2 is less than 35, so it is alkalotic.
Step 3: The HCO3 is normal.
Step 4: The PaCO2 matches the pH, because they are both alkalotic. Therefore the imbalance is
respiratory alkalosis. It is alkalotic because the pH is alkalotic; it is respiratory because the
PaCO2 moved opposite (ROME) and matches the pH.
Step 5: The HCO3 is normal, therefore there is no compensation. If the HCO3 was acidotic (low)
(opposite of the pH) then compensation (partial) would be present.
Step 6: Lastly, the PaO2 and SaO2 are normal indicating normal oxygenation (no hypoxemia).
The Full Interpretation for this ABG is: Uncompensated respiratory alkalosis.
This patient is hyperventilating. “Blowing off CO2”. Hyperventilation is fast and deep breathing
(increased Minute Volume) and increased Alveolar Minute Volume (areas that actually
participate in gas exchange in the lungs). Conditions that can cause this are: Anxiety, Pain, High
Altitudes, Fever, initial stages of Pulmonary embolism, hypoxia. Treatment for this patient
would be to treat the condition: anxiety medications, pain medications, fever reducers, etc.),
encourage patient to breath slow, possible rebreathing in paper bag to restore CO2.
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Example 3:
pH
7.18
acidotic
PaCO2
44
normal
PaO2
92
normal
SaO2
95%
normal
HCO3
16
acidotic
Step 1: The pH is less than 7.35, so it is acidotic.
Step 2: The PaCO2 is Normal.
Step 3: The HCO3 is less than 22, so it is acidotic.
Step 4: The HCO3 matches the pH, because they are both acidotic. Therefore the imbalance is
metabolic acidosis. It is acidotic because the pH is acidotic; it is metabolic because the HCO3
matches the pH.
Step 5: The PaCO2 is normal, therefore, no compensation.
Step 6: Lastly, the PaO2 and SaO2 are normal indicating normal oxygenation (no hypoxemia)
The full interpretation of this ABG is: Uncompensated Metabolic acidosis.
The patient has an acute metabolic disorder such as Diabetic Ketoacidosis (DKA), severe
starvation, Salisylate (Aspirin) Overdose, Shock, Sepsis, severe diarrhea, renal failure. Treatment
is to treat the underlying disorder, administer medication and fluids, replace electrolytes, and
dialysis.
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Example 4.
pH
7.30
acidotic
PaCO2
30
alkalotic
PaO2
68
low
SaO2
92%
low
HCO3
14
acidotic
Step 1: The pH is less than 7.35, so it is acidotic
Step 2: The PaCO2 is less than 35, so it is alkalotic.
Step 3: The HCO3 is less than 22, so it is acidotic.
Step 4: The HCO3 matches the pH, because both are acidotic. Therefore the imbalance is a
metabolic acidosis. It is acidotic because the pH is acidotic; it is metabolic because the HCO3
matches the pH.
Step 5: The PaCO2 is alkalotic and goes the opposite direction of the pH, so therefore there is
compensation. Because the pH is not in the normal range (7.35 – 7.45) the compensation is
called partial.
Step 6: Lastly, the PaO2 and the SaO2 are low indicating hypoxemia. (inadequate oxygenation).
The full interpretation for this ABG is: Partially-compensated metabolic acidosis with
hypoxemia.
There are a number of conditions that can cause metabolic acidosis: renal failure, severe
diarrhea, Aspirin overdose, DKA, Shock, and Sepsis. This patient is probably in shock because
the metabolic acidosis is associated with poor oxygenation.
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Example 5:
pH
7.60
alkalotic
PaCO2
56
acidotic
PaO2
92
normal
SaO2
98%
normal
HCO3
35
alkalotic
Step 1: The pH is greater than 7.45, so it is alkalotic.
Step 2: The PaCO2 is greater than 45, so it is acidotic.
Step 3: The HCO3 is greater than 26, so it is alkalotic.
Step 4: The HCO3 matches the pH, because both are alkalotic. Therefore the imbalance is a
metabolic alkalosis. It is alkalotic because the pH is alkalotic; it is metabolic because the HCO3
matches the pH.
Step 5: The PaCO2 is acidotic and goes the opposite direction of the pH, so therefore there is
compensation. Because the pH is not in the normal range (7.35 – 7.45) the compensation is
called partial.
Step 6: Lastly, the PaO2 and the SaO2 are normal indicating normal oxygenation (no
hypoxemia).
The full interpretation for this ABG is: Partially-compensated metabolic alkalosis.
The patient is probably losing stomach acid from vomiting, NG tube drainage/suctioning, use of
anti-acids or medications that reduce stomach acid, or potassium wasting diuretics (thiazides like
furosemide (Lasix).
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Example 6: (last one) (Full compensation – ohh shit! Now I am confused again!)
pH
7.38
normal
PaCO2
62
acidotic
PaO2
93
normal
SaO2
97%
normal
HCO3
35
alkalotic
Step 1: The pH is normal but less than 7.40, so it is within range but on the acidotic (low) side of
the normal range.
Step 2: The CO2 is greater than 45, so it is acidotic.
Step 3: The HCO3 is greater than 26 so it is alkalotic.
Step 4: The PaCO2 matches the pH, only because the normal pH is on the low side of the range
<7.40 (towards acidosis). So the primary imbalance is respiratory.
Step 5: The HCO3 is alkalotic and is going in the opposite direction of the normal pH; therefore
compensation is present from the renal system. The pH is between 7.35 and 7.40 (low normal),
so it is fully compensated. Therefore the imbalance is respiratory acidosis with full
compensation.
Step 6: Lastly, the PaO2 and SaO2 are both low indicating hypoxemia.
The Full Interpretation for this ABG is: Fully Compensated Respiratory Acidosis.
Notice that the only difference between partially and fully compensated states is whether or not
the pH has returned to within the normal range. In compensated acid-base disorders, the pH will
frequently fall either on the low or high side of neutral (7.40). Making note of where the pH falls
within the normal range is helpful in determining if the original acid-base disorder was acidosis
or alkalosis.
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Now test yourself: answer the questions
ABG Interpretation Review and Application:
Question 1:
A patient’s blood pH is decreasing. The nurse realizes that this patient’s hydrogen ion concentration is:
1. Increasing
2. Decreasing
3. Being affected by oxygen concentration
4. Stabilizing
Question 2:
A patient is admitted with the diagnosis of diabetic ketoacidosis. The nurse realizes that this patient’s
body will attempt to attain acid-base balance by:
1. Decreasing its respiratory rate.
2. Increasing the reabsorption of hydrogen ions.
3. Increasing the secretion of hydrogen ions.
4. Decreasing the reabsorption of bicarbonate.
Question 3: A patient has a respiratory rate of 20. The nurse calculates this patient’s minute ventilation to
be:
1. 1 L/min
2. 2 L/min
3. 5 L/min
4. 10 L/min
Question 4:
The nurse, admitting a patient with diabetes, believes the patient is attempting to correct an acidotic
condition. Which of the following did this nurse most likely observe while assessing this patient?
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1. Slow methodical respirations
2. Deep rapid respirations
3. Change in level of consciousness
4. Intact extraocular movements
Question 5:
The nurse is caring for a patient with metabolic acidosis. The nurse realizes that which of the following
laboratory values might be altered for this patient?
1. Ammonia
2. Blood-urea-nitrogen
3. Creatinine
4. Prothrombin
Question 6:
The nurse is reviewing a patient’s arterial blood gas results. Which of the following values should the
nurse study first?
1. PaCO2
2. HCO3
3. Compensation
4. pH
Question 7:
The nurse is caring for a patient with pneumonia who has arterial blood gas values of: pH 7.20, PaCO2 75,
HCO3- 26, PaO2 44. Which of the following would be a priority for this patient?
1. Assisting the patient to breathe into a paper bag.
2. Preparing to administer Sodium Bicarbonate IV.
3. Placement of the patient in high Fowler’s position.
4. Administration of the prn sedative available.
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Question 8:
A patient is admitted in respiratory acidosis secondary to barbiturate overdose. Which of the following
will the nurse most likely assess in this patient?
1. Kussmaul’s respirations
2. Seizures
3. Slow, shallow respirations
4. Increased deep tendon reflexes
Question 9:
The nurse is providing discharge instructions to a patient with respiratory alkalosis. Which of the
following statements indicates the patient understands the instructions?
1. “I will not take my Lasix without a potassium supplement.”
2. “I will not use Mylanta 5-6 times a day like I used to.”
3. “I will take a stress management class or seek counseling.”
4. “I will call my MD the next time I have diarrhea for a few days.”
Question 10:
A patient ABG’s come back as: pH: 7.33; PaCo2: 60; HCO3: 34, PaO2: 88; SaO2: 90%.
1.
2.
3.
4.
Uncompensated Respiratory Acidosis with hypoxemia.
Partially-compensated respiratory alkalosis with normal oxygenation.
Partially-compensated respiratory acidosis with hypoxemia.
Respiratory acidosis with full compensation and with hypoxemia.
Question 11:
Interpret the following ABG’s: pH: 7.48; PaCO2: 42; HCO3: 30; PaO2: 94; SaO2:100%.
1.
2.
3.
4.
Metabolic acidosis without compensation.
Respiratory alkalosis with partial compensation.
Respiratory alkalosis without compensation.
Metabolic alkalosis without compensation.
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Question 12:
In question 11, what is the oxygenation status?
1. Normal oxygenation
2. Hypoxemia
Question 13:
Interpret the following ABG’s: pH: 7.38; PaCO2: 38; HCO3: 24; PaO2: 96; SaO2:98%.
1.
2.
3.
4.
Respiratory Alkalosis
Normal ABG’s
Metabolic Alkalosis
None of the above
Question 14:
Interpret the following ABG’s: pH: 7.21; PaCO2: 60; HCO3: 24; PaO2: 66; SaO2:88%.
1.
2.
3.
4.
Normal ABG’s
Uncompensated Respiratory Acidosis with hypoxemia.
Partially-Compensated Metabolic Acidosis with hypoxemia.
Fully-compensated Respiratory Acidosis and normal oxygenation.
Question 15:
Interpret the following ABG results: pH: 7.42; PaCO2: 58; HCO3: 31.
1.
2.
3.
4.
Partially-compensated metabolic acidosis.
Fully compensated metabolic alkalosis.
Uncompensated metabolic alkalosis.
Fully compensated respiratory acidosis.
Question 16:
Interpret the following ABG results: pH: 7.36; PaCO2: 29; HCO3: 19.
1.
2.
3.
4.
Fully compensated respiratory acidosis
Fully compensated respiratory alkalosis
Fully compensated metabolic acidosis
Fully compensated metabolic alkalosis
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