PCT Oxygen and Respiratory Assistance 2 — Questions and Answers
Question 1: A nasal cannula delivers oxygen at flow rates of:
- 1-6 liters per minute (Correct answer)
- 8-15 liters per minute
- 20-30 liters per minute
- 0.5 liters per minute only
Correct answer: 1-6 liters per minute
Nasal cannulas deliver low-flow oxygen at 1-6 L/min, providing approximately 24-44% FiO2 depending on the flow rate.
The nasal cannula is a low-flow device with two prongs inserted into the nostrils. Each liter per minute increases FiO2 by approximately 4%: 1 L/min = 24%, 2 L/min = 28%, 3 L/min = 32%, 4 L/min = 36%, 5 L/min = 40%, 6 L/min = 44%. Flow rates above 6 L/min dry mucous membranes without significantly increasing oxygen delivery. Humidification is typically added at flows above 4 L/min.
Question 2: Which safety precaution is essential when oxygen is in use?
- Keep all electrical equipment turned off in the entire building
- Post 'No Smoking' signs and remove open flames from the area (Correct answer)
- Ensure the patient wears rubber-soled shoes at all times
- Keep windows sealed to prevent oxygen from escaping
Correct answer: Post 'No Smoking' signs and remove open flames from the area
Oxygen supports combustion and makes fires burn faster and hotter, so all ignition sources must be eliminated from the area.
Oxygen is an accelerant—it does not burn itself but makes other materials ignite more easily and burn more intensely. Safety measures include: no smoking within the designated area, remove candles and open flames, avoid oil-based products near oxygen (petroleum jelly, certain lotions), use cotton blankets (not wool or synthetics that create static), keep electrical equipment in good repair, and post oxygen-in-use signs. The PCT must enforce these rules with patients and visitors.
Question 3: When suctioning a patient's airway, the PCT should apply suction for no longer than:
- 30 seconds
- 10-15 seconds (Correct answer)
- 60 seconds
- 5 minutes
Correct answer: 10-15 seconds
Suctioning removes air along with secretions, so limiting each pass to 10-15 seconds prevents hypoxia and mucosal trauma.
Suctioning should be limited to 10-15 seconds per pass to prevent hypoxia (oxygen is removed along with secretions), cardiac arrhythmias (vagal stimulation), and mucosal damage. Pre-oxygenate with 100% O2 before suctioning. Apply suction only while withdrawing the catheter using a rotating motion. Allow the patient to rest and reoxygenate between passes. Monitor SpO2 and heart rate throughout. Report excessive or unusual secretions to the nurse.
Question 4: Deep breathing and coughing exercises are important for post-operative patients because they:
- Help patients fall asleep faster
- Prevent atelectasis and promote lung expansion (Correct answer)
- Reduce the need for pain medication
- Speed up wound healing directly
Correct answer: Prevent atelectasis and promote lung expansion
Post-surgical patients breathe shallowly due to pain, which can cause alveolar collapse (atelectasis). Deep breathing and coughing expand the lungs and clear secretions.
Atelectasis (alveolar collapse) is the most common post-operative pulmonary complication, occurring when shallow breathing fails to fully inflate lung segments. Deep breathing exercises expand alveoli, while coughing mobilizes secretions. The PCT should encourage patients to use an incentive spirometer (inhale slowly, hold for 3-5 seconds), take 10 deep breaths every hour, and splint the incision with a pillow when coughing. Early ambulation also promotes lung expansion.
Question 5: The PCT notices that the oxygen tubing has become disconnected from the wall outlet. The FIRST action should be:
- Find the nurse to report it
- Reconnect the tubing immediately (Correct answer)
- Document the disconnection in the chart
- Turn off the oxygen flow meter first
Correct answer: Reconnect the tubing immediately
Immediate reconnection restores oxygen delivery to the patient, preventing desaturation and hypoxia.
An oxygen disconnection is an immediate patient safety issue. The PCT should reconnect the tubing right away, then verify the flow rate matches the order, check that the patient is receiving oxygen (nasal prongs in place, condensation in mask), and assess the patient for signs of hypoxia (cyanosis, confusion, tachycardia, low SpO2). Report the disconnection to the nurse and document the event, including duration if known.
Question 6: Incentive spirometry is used to:
- Measure oxygen levels in the blood
- Encourage deep breathing and prevent pulmonary complications (Correct answer)
- Deliver aerosolized medication to the lungs
- Measure the patient's lung capacity for diagnosis
Correct answer: Encourage deep breathing and prevent pulmonary complications
The incentive spirometer provides visual feedback as the patient inhales deeply, encouraging sustained maximal inspiration to prevent atelectasis.
The incentive spirometer is a handheld device with a piston or ball that rises as the patient inhales. The patient seals their lips around the mouthpiece, inhales slowly and deeply to raise the indicator to the target level, and holds the breath for 3-5 seconds before exhaling. This sustained maximal inspiration prevents and treats atelectasis. The PCT should encourage use every 1-2 hours while awake, document the achieved volume, and report inability to reach the target.
PCT Oxygen and Respiratory Assistance 2
A nasal cannula delivers oxygen at flow rates of: