DAANCE Anesthesia Equipment and Delivery 4 — Questions and Answers
Question 1: What is the primary purpose of a scavenging system in a dental anesthesia setup?
- To humidify exhaled gases
- To collect and remove waste anesthetic gases from the operatory (Correct answer)
- To filter the nitrous oxide supply line
- To monitor oxygen saturation levels
Correct answer: To collect and remove waste anesthetic gases from the operatory
Scavenging systems capture waste anesthetic gases (especially nitrous oxide) to prevent occupational exposure to dental personnel.
Question 2: Which component of the nitrous oxide delivery system is responsible for reducing high tank pressure to a safe working pressure?
- Flowmeter
- Reservoir bag
- Pressure regulator (Correct answer)
- Check valve
Correct answer: Pressure regulator
The pressure regulator reduces the high cylinder pressure to a lower, safe working pressure suitable for delivery to the patient.
Question 3: A dental anesthesia machine failsafe mechanism is designed to:
- Shut off nitrous oxide flow if oxygen pressure drops below a threshold (Correct answer)
- Alert staff when the reservoir bag is full
- Prevent oxygen from flowing when nitrous is depleted
- Automatically increase gas flow during deep sedation
Correct answer: Shut off nitrous oxide flow if oxygen pressure drops below a threshold
The failsafe mechanism automatically shuts off or limits nitrous oxide delivery if oxygen supply pressure falls below a set minimum, preventing hypoxic mixtures.
Question 4: When inspecting nitrous oxide cylinders before use, a DAANCE-certified assistant should verify the cylinder color code. In the United States, nitrous oxide cylinders are:
- Green
- Blue (Correct answer)
- Gray
- Yellow
Correct answer: Blue
In the US, nitrous oxide cylinders are color-coded blue, while oxygen cylinders are green.
Question 5: The reservoir bag on a nitrous oxide/oxygen delivery system serves which function during inhalation sedation?
- Stores excess gas and allows monitoring of respiratory rate and depth (Correct answer)
- Removes carbon dioxide from exhaled gases
- Regulates the ratio of nitrous oxide to oxygen
- Prevents backflow of gases into the supply lines
Correct answer: Stores excess gas and allows monitoring of respiratory rate and depth
The reservoir bag acts as a gas reservoir and allows the clinician to visually monitor the patient's breathing rate and tidal volume.
Question 6: Which type of nasal hood (mask) is most appropriate for a pediatric patient receiving nitrous oxide sedation?
- A standard adult-sized mask trimmed to fit
- A pediatric-sized mask designed for smaller facial anatomy (Correct answer)
- An oral/nasal mask that covers both nose and mouth
- Any mask size is acceptable as long as flow rates are adjusted
Correct answer: A pediatric-sized mask designed for smaller facial anatomy
A properly sized pediatric nasal mask ensures an adequate seal and accurate gas delivery, minimizing leakage and environmental contamination.
Question 7: During nitrous oxide administration, the flowmeter indicates a total flow of 6 L/min with 30% nitrous oxide. How many liters per minute of oxygen is the patient receiving?
- 1.8 L/min
- 3.0 L/min
- 4.2 L/min (Correct answer)
- 2.4 L/min
Correct answer: 4.2 L/min
If 30% of 6 L/min is nitrous oxide (1.8 L/min), then oxygen accounts for 70%, which equals 4.2 L/min.
DAANCE Anesthesia Equipment and Delivery 4
What is the primary purpose of a scavenging system in a dental anesthesia setup?