3 MAXE • 422 RN
★ ★
C College of Nursing
J O U R N E Y T O E X T R A O R D I N A R Y CO M PA S S I O N AT E C A R E
EST. 1889
NR 224 — Examination 3
F U N D A M E N TA LS O F N U R S I N G : OX YG E N AT I O N , M E D I C AT I O N A D M I N I ST R AT I O N & B O W E L
E L I M I N AT I O N
INSTITUTION Chamberlain University COURSE CODE NR 224
PROGRAM Bachelor of Science in Nursing (BSN) ACADEMIC YEAR
EXAM TITLE Examination 3 — Fundamentals of Nursing TOTAL QUESTIONS 29 Questions
COURSE TITLE Fundamentals of Nursing FORMAT Multiple Choice — Select the Single Best
Answer
EXAMINATION INSTRUCTIONS
▸ Select the single best answer for each question unless otherwise instructed.
▸ Oxygen therapy devices, flow rates, FiO2 percentages, and safety precautions are core competencies.
▸ Medication administration routes, injection angles, the seven rights, and Z-track technique are emphasized.
▸ Bowel elimination assessment, Bristol Stool Chart classification, enema types, and ostomy care are testable content.
▸ Suctioning technique, NG tube placement verification, and hyperventilation/hypoventilation pathophysiology are essential
concepts.
▸ Correct answers and clinical rationales appear below each question for NCLEX board review purposes.
▸ All content reflects current evidence-based nursing practice and ANA standards.
SECTION I — OXYGENATION: PHYSIOLOGY, ASSESSMENT & OXYGEN Questions 1 –
THERAPY DEVICES 16
1. What are the characteristics of oxygen as a drug?
A. A colored, scented gas that is harmless at any concentration; no physician order required
B. Clear, odorless gas that constitutes approximately 21% of the air we breathe; considered a drug with potential for
toxic effects; goal is optimal SpO2 with lowest effective dose; requires a physician's order
C. A liquid that must be refrigerated; constitutes 50% of room air
D. A gas that is safe at any concentration and does not require monitoring
CORRECT ANSWER B — Clear, odorless gas that constitutes approximately 21% of the air we breathe; considered a drug
with potential for toxic effects; goal is optimal SpO2 with lowest effective dose; requires a physician's
order
RATIONALE Oxygen is a clear, odorless gas that constitutes approximately 21% of atmospheric air. It is classified as a drug
and requires a physician's order for administration. Like any drug, oxygen has therapeutic effects, adverse
effects, and toxic potential. High concentrations can cause oxygen toxicity (pulmonary damage from free
radical formation) and suppress the respiratory drive in some COPD patients. The goal of therapy is to achieve
optimal oxygen saturation (generally SpO2 92-96% for most patients, 88-92% for COPD patients at risk for CO2
retention) using the lowest effective dose. Oxygen supports combustion — strict fire safety precautions are
essential.
, 2. Why is oxygen considered a drug?
A. It is available over the counter without any restrictions
B. Need a physician's order to give to patient; patient comfort and toxic effects require nursing assessment
C. It is manufactured by pharmaceutical companies only
D. It is administered only in emergency situations
CORRECT ANSWER B — Need a physician's order to give to patient; patient comfort and toxic effects require nursing
assessment
RATIONALE Oxygen is legally and clinically considered a drug because: (1) It requires a physician's order with specified
dose (flow rate in L/min or FiO2 percentage), route (nasal cannula, mask, etc.), and frequency (continuous,
PRN, during activity). (2) It has therapeutic dose ranges — too little results in hypoxemia; too much can cause
oxygen toxicity, absorption atelectasis, and CO2 retention in vulnerable patients. (3) It requires nursing
assessment — monitoring SpO2, respiratory status, patient comfort, and signs of toxicity. (4) It has adverse
effects. Oxygen is administered like any other medication — the nurse applies the rights of medication
administration, assesses for therapeutic response, and monitors for complications.
3. What is the percentage of oxygen in room air?
A. 10%
B. 21%
C. 50%
D. 78%
CORRECT ANSWER B — 21%
RATIONALE Room air (atmospheric air at sea level) contains approximately 21% oxygen (FiO2 = 0.21), 78% nitrogen, and
1% trace gases (argon, carbon dioxide, etc.). This 21% is the baseline from which supplemental oxygen
therapy is added. A nasal cannula at 1 L/min increases FiO2 to approximately 24% — an increase of only 3%
above room air. At 6 L/min, FiO2 is approximately 44% — about double room air. Understanding that room air
is 21% oxygen helps the nurse appreciate that even "low-flow" oxygen devices deliver significantly more
oxygen than atmospheric air. The term "room air" in clinical documentation means the patient is breathing
without supplemental oxygen.
4. What is the goal of oxygen therapy?
A. Provide the highest possible oxygen concentration regardless of patient need
B. Provide optimal oxygen saturation with the lowest, most effective dose; promote and maintain adequate
oxygenation; treat underlying process; reduce dyspnea
C. Replace all room air with pure oxygen
D. Sedate the patient to reduce oxygen consumption
CORRECT ANSWER B — Provide optimal oxygen saturation with the lowest, most effective dose; promote and maintain
adequate oxygenation; treat underlying process; reduce dyspnea
RATIONALE The goal of oxygen therapy is to provide optimal oxygen saturation using the lowest effective dose — NOT to
give the maximum possible oxygen. Over-oxygenation is harmful: in patients with chronic CO2 retention
(COPD), high oxygen levels can suppress the hypoxic respiratory drive, leading to hypoventilation and
worsening hypercapnia. In all patients, prolonged high FiO2 can cause oxygen toxicity (free radical damage to
alveolar-capillary membranes), absorption atelectasis (nitrogen washout causing alveolar collapse), and
increased oxidative stress. The nurse titrates oxygen to target SpO2 (typically 92-96% for most patients, 88-
92% for COPD patients) and weans oxygen as the patient improves. The underlying condition causing
hypoxemia must also be treated.