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DOH Respiratory Nursing Practice Questions
Respiratory questions test oxygen therapy, airway care and recognising respiratory failure, including the classic COPD and asthma scenarios. Below are 5 free sample questions for the DOH Registered Nurse exam, each with the answer and a rationale.
What this topic covers
- Oxygen delivery devices and target saturations
- COPD and controlled oxygen
- Asthma management and inhaler technique
- Chest drains and tracheostomy care
- ABG interpretation
- TB and pneumonia nursing care
The full bank has 89 respiratory nursing questions, part of 1,500 questions across 16 nursing topics.
Free DOH respiratory nursing questions
1. What is the approximate range of oxygen concentration (FiO2) delivered by a nasal cannula at 1–6 L/min?
- A. 24–44%
- B. 50–60%
- C. 60–80%
- D. Up to 95%
Show answer and rationale
Each litre per minute via nasal cannula adds roughly 4% to room air (21%), giving about 24–44% at 1–6 L/min. Higher concentrations require masks such as a non-rebreather.
Reference: Lewis Medical-Surgical Nursing – oxygen therapy
2. When suctioning a patient's tracheostomy, how long should suction be applied during each pass of the catheter?
- A. Up to 30 seconds
- B. Continuously while inserting and withdrawing
- C. No more than 10–15 seconds
- D. At least 20 seconds
Show answer and rationale
Suction should be applied only on withdrawal and for no more than 10–15 seconds per pass to prevent hypoxaemia, mucosal trauma and bradycardia. The patient should be pre-oxygenated and allowed to recover between passes.
Reference: Potter & Perry – airway suctioning
3. Which intervention helps most to prevent hospital-acquired pneumonia in a postoperative patient?
- A. Encouraging early mobilisation, deep breathing and coughing
- B. Keeping the patient on bed rest for 48 hours
- C. Giving prophylactic antibiotics to all surgical patients for a week
- D. Restricting oral fluids
Show answer and rationale
Early mobilisation, deep breathing, coughing and incentive spirometry help expand the lungs and clear secretions, reducing atelectasis and pneumonia. Prolonged bed rest increases risk, and fluid restriction thickens secretions.
Reference: Potter & Perry – postoperative care
4. A patient uses an inhaled corticosteroid twice daily. Which teaching point is most important to prevent a common adverse effect?
- A. Take the inhaler only during an acute attack
- B. Use the inhaler immediately before meals
- C. Hold the breath for 60 seconds after inhaling
- D. Rinse the mouth with water and spit after each use
Show answer and rationale
Rinsing the mouth after an inhaled corticosteroid reduces the risk of oral candidiasis (thrush) and hoarseness. Inhaled corticosteroids are preventers and do not relieve acute attacks.
Reference: Standard nursing pharmacology – inhaled corticosteroids
5. A patient with a chest injury has severe dyspnoea, hypotension, distended neck veins and a trachea deviated to the left. Breath sounds are absent on the right. What does the nurse recognise?
- A. Tension pneumothorax requiring immediate decompression
- B. Simple pneumothorax requiring observation
- C. Cardiac tamponade requiring pericardiocentesis only
- D. Left-sided haemothorax
Show answer and rationale
Tension pneumothorax causes mediastinal shift away from the affected side, tracheal deviation, distended neck veins and hypotension; it is a life-threatening emergency requiring immediate needle decompression. Tamponade does not cause tracheal deviation or unilateral absent breath sounds.
Reference: Lewis Medical-Surgical Nursing – chest trauma
Study tip
Know the COPD target saturation range (88–92%) and when an asthma attack is becoming life-threatening (silent chest, exhaustion, falling SpO2).
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