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NUR 2392 EXAM 2 LATEST 2023-2024 /NUR2392 MULTIDIMENSIONAL CARE 2 EXAM
2/MDC2 EXAM 2 ACTUAL EXAM 75 QUESTIONS AND CORRECT DETAILED
ANSWERS|AGRADE (RASMUSSEN COLLEGE)
- Which pH value indicates the highest concentration of free hydrogen ions in the blood and other
extracellular fluids?
A. 7.57
B. 7.47
C. 7.37
D. 7.27
The blood level of free hydrogen ions is calculated in negative logarithm units. This calculation makes the value of
pH inversely related (negatively related) to the concentration of free hydrogen ions. Thus, the lower the pH value
of a fluid, the higher the level of free hydrogen ions in that fluid. - Which client arterial blood gas results would the nurse interpret as within normal limits?
A. pH 7.28, PaCO2 24, bicarbonate 15, PaO2 95
B. pH 7.45, PaCO2 41, bicarbonate 25, PaO2 97
C. pH 7.35, PaCO2 24, bicarbonate 15, PaO2 95
D. pH 7.30, PaCO2 66, bicarbonate 38, PaO2 70 The normal arterial pH range is 7.35-7.45. The normal
PaCO2 range is 35-45 mm Hg.
The normal PaO2 range is 80-100 mm Hg.
The normal arterial bicarbonate range is 21-28 mEq/L (mmol/L). - Which arterial blood pH level can be fatal?
A. 7.22 B. 7.11
C. 7.05
D. 6.85
An arterial pH below 6.85 is considered incompatible with life because all vital organ functions would be
inhibited. - By which mechanism do buffers help maintain arterial blood pH within the normal range?
A. Binding excess free hydrogen ions
B. Increasing kidney excretion of free hydrogen ions
C. Triggering increased bicarbonate production in the pancreas
D. Stimulating respiratory neurons to increase the rate and depth of ventilation
Buffers in body fluids act like hydrogen ion “sponges,” soaking up hydrogen ions when too many are present and
squeezing out hydrogen ions when very few are present. Buffers have no mechanism to change kidney, pancreas,
or neuronal function. - What changes in body functions does the nurse anticipate in a client who has lower than normal blood
pH levels? Select all that apply.
A. Decreased serum potassium levels
B. Increased effectiveness of drugs
C. Reduced function of hormones
D. Increased function of enzymes
E. Decreased electrical conduction in the heart
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F. Decreased skeletal muscle strength
Higher concentration of hydrogen ions (reflected by a lower pH) increases (not decreases) serum potassium
levels, decreases effectiveness of drugs, reduces function of hormones, reduces function of enzymes, slows
electrical conduction through the heart (because of the elevated potassium levels) and decreases muscle strength.
- The continuous normal function of which organs is most critical for acid-base balance? Select all that
apply.
A. Adrenal glands
B. Bladder
C. Heart
D. Kidneys
E. Liver
F. Lungs
The kidneys are critical in retaining and eliminating hydrogen ions and bicarbonate to maintain acid-base
balance. The lungs are the organs that control carbon dioxide elimination. Normal functioning of both these
organs are necessary for acid-base balance. A problem interfering with the function of either of them can lead to
life-threatening acid-base imbalances. The heart, liver, and bladder have no role in acid-base balance. Although
specific adrenal gland problems are indirectly associated with acid-base imbalances, they do not directly affect
acid-base balance. - Which statement most accurately describes the relationship between the hydrogen ion concentration and
carbon dioxide concentration in extracellular fluids?
A. Because carbon dioxide is a gas and hydrogen ions are electrolytes, these two substances have no
relationship in extracellular fluids.
The concentrations of hydrogen ions and carbon dioxide are directly related, with an increase or
decrease in one always resulting in a corresponding increase or decrease in the other.
C. Carbon dioxide buffers hydrogen ions, thus these two concentrations are inversely related to each other.
The greater the carbon dioxide concentration, the fewer hydrogen ions present in that fluid.
D. Hydrogen ions and carbon dioxide ions exist in a balanced relationship as a result of their charges. The
positively charged hydrogen ions are attracted to the negatively charged carbon dioxide ions, forming an
electrically neutral substance.
Through the action of the carbonic anhydrase reaction, the concentration of hydrogen ions is directly related to
the concentration of carbon dioxide in the blood. Any condition that increases the concentration of one also
increases the concentration of the other. Carbon dioxide is not a buffer. - Which statement about compensation for acid-base imbalance is accurate? A. The respiratory system is
less sensitive to acid-base changes.
B. The respiratory system can begin compensation within seconds to minutes.
C. The renal system is less powerful than the respiratory system.
D. The renal system is more sensitive to acid-base changes.
The healthy respiratory system can compensate for acid-base imbalances from other causes. It represents the
second line of defense to prevent an imbalance and can begin to compensate within seconds to minutes after a
change in hydrogen ion concentration (reflected as a corresponding change in carbon dioxide). The central
chemoreceptors controlling rate and depth of ventilation are extremely sensitive to changes in carbon dioxide
levels. - Which condition or response is an example of physiologic compensation to maintain acid-base balance?
A. Increasing rate and depth of respiration when running 2000 feet
B.
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B. Increasing urine output when blood pressure increases during heavy exercise
C. Drinking more fluids when spending an extended period of time in a dry environment
D. Shifting body weight when pain occurs as a result of remaining in one position for too long
The respiratory system increases its activity by “blowing off” excess carbon dioxide that developed as a result of
lactic acidosis occurring in skeletal muscle when blood flow and oxygenation were insufficient to meet the
increased demand for oxygen (oxygen debt) created during increased skeletal muscle metabolism.
- Which statements correctly apply to acid-base balance in the body? Select all that apply.
B. The immediate binding of excess hydrogen ions occurs primarily in the red blood cells.
C. Combined acidosis is less severe than either metabolic acidosis or respiratory acidosis alone.
D. Respiratory acidosis is caused by a patent airway.
E. Acid-base balance occurs through control of hydrogen ion production and elimination.
F. Buffers are the third-line defense against acid-base imbalances in the body.
Acid-base balance is maintained by controlling the body’s hydrogen ion production with mechanisms to eliminate
hydrogen ions at the same rate they are produced. Renal mechanisms for control of acid-base balance are the
most powerful but are slow to start, usually requiring that an acid-base disturbance be present for at least 24
hours before becoming active. The first line of defense against acid-base changes are the buffers in the blood,
other extracellular fluids, and inside cells. Red blood cells in particular can reduce excess hydrogen ions by having
them enter the cells and then binding them to buffers and hemoglobin. Respiratory acidosis is caused by
problems that interfere with effective ventilation. A patent airway never causes respiratory acidosis. When
conditions that cause respiratory acidosis are present at the same time as conditions that cause metabolic
acidosis, the severity of the imbalance increases, not decreases. - Which alteration in acid-base balance does the nurse expect to see as a compensatory response in a client
who has a long-term severe respiratory impairment?
A. Decreased arterial blood pH
B. Increased arterial blood oxygen
C. Increased arterial blood bicarbonate
D. Decreased arterial blood carbon dioxide
Because kidneys regulate pH by controlling bicarbonate concentration and the lungs regulate pH by controlling
carbon dioxide loss, a loss of one function can be at least partially compensated by the other function. When
pulmonary function is decreased so that adequate amounts of carbon dioxide are not excreted, the pH drops,
stimulating the kidneys to reabsorb more bicarbonate to balance the increased acid production. - Which specific type of medication reported as taken daily by an older client will cause a nurse to assess
for indications of an acid-base imbalance?
A. Antilipidemics
B. Hormonal therapy
C. Diuretics
D. Antidysrhythmics
Of all the drug categories listed, only the diuretics induce the excretion of specific electrolytes and hydrogen ions,
leading to the development of acid-base imbalances.
Renal mechanisms are stronger in regulating acid-base balance but slower to respond than respiratory
mechanisms.
A.