Miami Dade College
2 MAXE · 2CDM
★ ★
MDC Medical Campus — School of Nursing
EST. 1960
THE COLLEGE OF THE AMERICAN DREAM.
MDC2 — Examination 2
A B G I N T E R P R E TAT I O N · AC I D - B A S E · F LU I D & E L E CT R O LYT E S · I V S O LU T I O N S · E KG
CHANGES
INSTITUTION Miami Dade College COURSE CODE MDC2
PROGRAM Associate of Science in Nursing — ACADEMIC YEAR
ADN
EXAM TITLE MDC2 Examination 2 — COURSE TITLE Med-Surg Nursing II
Comprehensive
TOTAL QUESTIONS 84 Questions FORMAT Multiple Choice — Select the
Single Best Answer
EXAMINATION INSTRUCTIONS
▸ Select the single best answer for each multiple-choice question unless otherwise instructed.
▸ Content covers ABG interpretation, acid-base compensation, fluid and electrolyte imbalances, IV
solutions, EKG changes, and nursing interventions.
▸ Normal reference ranges are provided within rationales.
▸ Correct answers and clinical rationales appear below each question for board review purposes.
, COMPREHENSIVE EXAMINATION Questions 1 – 84
1. How is a fully compensated ABG characterized?
A. pH is abnormal and all values are abnormal
B. pH is normal while PaCO₂ and HCO₃⁻ are abnormal
C. pH and one other value are abnormal
D. All three values are within normal limits
CORRECT ANSWER B — pH is normal while PaCO₂ and HCO₃⁻ are abnormal.
RATIONALE Fully compensated: the pH has returned to the normal range (7.35–7.45) because
the compensatory mechanism (lungs or kidneys) has fully corrected the pH.
However, both PaCO₂ and HCO₃⁻ remain abnormal — one reflects the primary
disorder, the other reflects compensation. The body never overcompensates —
the pH will be on the same side of 7.40 as the original disorder.
2. How is partial compensation characterized on an ABG?
A. pH is normal, PaCO₂ and HCO₃⁻ are normal
B. pH, CO₂, and HCO₃⁻ are all off — some compensation occurs but pH remains abnormal
C. pH and one other value are abnormal
D. Only the PaCO₂ is abnormal
CORRECT ANSWER B — pH, CO₂, and HCO₃⁻ are all off — some compensation occurs but pH
remains abnormal.
RATIONALE Partially compensated: ALL THREE values are abnormal. The compensating organ
(lungs for metabolic disorders, kidneys for respiratory disorders) has begun to
respond but has not yet fully corrected the pH. Example: pH 7.28, PaCO₂ 32, HCO₃⁻
16 (partially compensated metabolic acidosis — the lungs are hyperventilating
but pH is still acidotic).
,3. What characterizes an uncompensated ABG?
A. pH is normal and both other values are abnormal
B. All three values are abnormal
C. pH and one other value are abnormal
D. All values are within normal limits
CORRECT ANSWER C — pH and one other value are abnormal.
RATIONALE Uncompensated: pH is abnormal and ONLY ONE other value (either PaCO₂ or
HCO₃⁻) is abnormal — the other remains within normal limits, indicating the body
has not yet begun compensation. Example: pH 7.30, PaCO₂ 58, HCO₃⁻ 26
(uncompensated respiratory acidosis — only PaCO₂ is abnormal, HCO₃⁻ is normal).
4. Crystalloid IV solutions contain small particles that easily pass through a semipermeable
membrane. How are they classified?
A. Colloid, albumin, and dextran
B. Isotonic, hypotonic, and hypertonic
C. Cationic, anionic, and neutral
D. Acidic, basic, and neutral
CORRECT ANSWER B — Isotonic, hypotonic, and hypertonic.
RATIONALE Crystalloids are classified by their tonicity relative to plasma: (1) Isotonic (0.9%
NS, LR) — same osmolality as plasma, stays in the ECF, used for fluid volume
deficits. (2) Hypotonic (0.45% NS) — lower osmolality, shifts water into cells, used
for intracellular dehydration (DKA, HHS). (3) Hypertonic (3% NaCl) — higher
osmolality, pulls water from cells into the ECF, used as a volume expander. Choice
depends on the patient's condition and deficits.
, 5. What is the primary purpose of isotonic IV solutions?
A. Increase intracellular volume and treat intracellular dehydration
B. Increase intravascular volume and treat fluid volume deficits
C. Pull fluid from cells into the extracellular space
D. Provide free water for hypernatremia correction
CORRECT ANSWER B — Increase intravascular volume and treat fluid volume deficits.
RATIONALE Isotonic solutions (0.9% NS, Lactated Ringer's) have the same effective osmolality
as plasma. When infused, they remain in the extracellular space, expanding
intravascular volume without causing fluid shifts between compartments. They
are the standard initial resuscitation fluids for hypovolemia, dehydration,
hemorrhage, and blood product administration. Hypotonic solutions increase
intracellular volume; hypertonic solutions pull fluid from cells.
6. Hypotonic IV solutions are used to treat which conditions?
A. Fluid volume deficits and hemorrhage
B. Intracellular dehydration from conditions such as diabetic ketoacidosis and hyperosmolar
hyperglycemia states
C. Expanding extracellular volume as a volume expander
D. Severe hyponatremia with cerebral edema
CORRECT ANSWER B — Intracellular dehydration from conditions such as DKA and
hyperosmolar hyperglycemia states.
RATIONALE Hypotonic solutions (0.45% NS, D5W in vivo) have lower osmolality than plasma.
Water shifts from the vascular space into cells, making them swell and correcting
intracellular dehydration. They are indicated for conditions with
hypertonicity/hypernatremia where cells have lost water — DKA, HHS, and
hypernatremia. They are NOT appropriate for hypovolemic shock (isotonic fluids
needed). Hypertonic solutions are used as volume expanders.
2 MAXE · 2CDM
★ ★
MDC Medical Campus — School of Nursing
EST. 1960
THE COLLEGE OF THE AMERICAN DREAM.
MDC2 — Examination 2
A B G I N T E R P R E TAT I O N · AC I D - B A S E · F LU I D & E L E CT R O LYT E S · I V S O LU T I O N S · E KG
CHANGES
INSTITUTION Miami Dade College COURSE CODE MDC2
PROGRAM Associate of Science in Nursing — ACADEMIC YEAR
ADN
EXAM TITLE MDC2 Examination 2 — COURSE TITLE Med-Surg Nursing II
Comprehensive
TOTAL QUESTIONS 84 Questions FORMAT Multiple Choice — Select the
Single Best Answer
EXAMINATION INSTRUCTIONS
▸ Select the single best answer for each multiple-choice question unless otherwise instructed.
▸ Content covers ABG interpretation, acid-base compensation, fluid and electrolyte imbalances, IV
solutions, EKG changes, and nursing interventions.
▸ Normal reference ranges are provided within rationales.
▸ Correct answers and clinical rationales appear below each question for board review purposes.
, COMPREHENSIVE EXAMINATION Questions 1 – 84
1. How is a fully compensated ABG characterized?
A. pH is abnormal and all values are abnormal
B. pH is normal while PaCO₂ and HCO₃⁻ are abnormal
C. pH and one other value are abnormal
D. All three values are within normal limits
CORRECT ANSWER B — pH is normal while PaCO₂ and HCO₃⁻ are abnormal.
RATIONALE Fully compensated: the pH has returned to the normal range (7.35–7.45) because
the compensatory mechanism (lungs or kidneys) has fully corrected the pH.
However, both PaCO₂ and HCO₃⁻ remain abnormal — one reflects the primary
disorder, the other reflects compensation. The body never overcompensates —
the pH will be on the same side of 7.40 as the original disorder.
2. How is partial compensation characterized on an ABG?
A. pH is normal, PaCO₂ and HCO₃⁻ are normal
B. pH, CO₂, and HCO₃⁻ are all off — some compensation occurs but pH remains abnormal
C. pH and one other value are abnormal
D. Only the PaCO₂ is abnormal
CORRECT ANSWER B — pH, CO₂, and HCO₃⁻ are all off — some compensation occurs but pH
remains abnormal.
RATIONALE Partially compensated: ALL THREE values are abnormal. The compensating organ
(lungs for metabolic disorders, kidneys for respiratory disorders) has begun to
respond but has not yet fully corrected the pH. Example: pH 7.28, PaCO₂ 32, HCO₃⁻
16 (partially compensated metabolic acidosis — the lungs are hyperventilating
but pH is still acidotic).
,3. What characterizes an uncompensated ABG?
A. pH is normal and both other values are abnormal
B. All three values are abnormal
C. pH and one other value are abnormal
D. All values are within normal limits
CORRECT ANSWER C — pH and one other value are abnormal.
RATIONALE Uncompensated: pH is abnormal and ONLY ONE other value (either PaCO₂ or
HCO₃⁻) is abnormal — the other remains within normal limits, indicating the body
has not yet begun compensation. Example: pH 7.30, PaCO₂ 58, HCO₃⁻ 26
(uncompensated respiratory acidosis — only PaCO₂ is abnormal, HCO₃⁻ is normal).
4. Crystalloid IV solutions contain small particles that easily pass through a semipermeable
membrane. How are they classified?
A. Colloid, albumin, and dextran
B. Isotonic, hypotonic, and hypertonic
C. Cationic, anionic, and neutral
D. Acidic, basic, and neutral
CORRECT ANSWER B — Isotonic, hypotonic, and hypertonic.
RATIONALE Crystalloids are classified by their tonicity relative to plasma: (1) Isotonic (0.9%
NS, LR) — same osmolality as plasma, stays in the ECF, used for fluid volume
deficits. (2) Hypotonic (0.45% NS) — lower osmolality, shifts water into cells, used
for intracellular dehydration (DKA, HHS). (3) Hypertonic (3% NaCl) — higher
osmolality, pulls water from cells into the ECF, used as a volume expander. Choice
depends on the patient's condition and deficits.
, 5. What is the primary purpose of isotonic IV solutions?
A. Increase intracellular volume and treat intracellular dehydration
B. Increase intravascular volume and treat fluid volume deficits
C. Pull fluid from cells into the extracellular space
D. Provide free water for hypernatremia correction
CORRECT ANSWER B — Increase intravascular volume and treat fluid volume deficits.
RATIONALE Isotonic solutions (0.9% NS, Lactated Ringer's) have the same effective osmolality
as plasma. When infused, they remain in the extracellular space, expanding
intravascular volume without causing fluid shifts between compartments. They
are the standard initial resuscitation fluids for hypovolemia, dehydration,
hemorrhage, and blood product administration. Hypotonic solutions increase
intracellular volume; hypertonic solutions pull fluid from cells.
6. Hypotonic IV solutions are used to treat which conditions?
A. Fluid volume deficits and hemorrhage
B. Intracellular dehydration from conditions such as diabetic ketoacidosis and hyperosmolar
hyperglycemia states
C. Expanding extracellular volume as a volume expander
D. Severe hyponatremia with cerebral edema
CORRECT ANSWER B — Intracellular dehydration from conditions such as DKA and
hyperosmolar hyperglycemia states.
RATIONALE Hypotonic solutions (0.45% NS, D5W in vivo) have lower osmolality than plasma.
Water shifts from the vascular space into cells, making them swell and correcting
intracellular dehydration. They are indicated for conditions with
hypertonicity/hypernatremia where cells have lost water — DKA, HHS, and
hypernatremia. They are NOT appropriate for hypovolemic shock (isotonic fluids
needed). Hypertonic solutions are used as volume expanders.
