Nitrous Oxide Sedation: Clinical & OSHA Safety Review

~ Exam ~

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This test has 25 questions.

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1. The benefits of Nitrous Oxide sedation include:

  a. Increases patient comfort

  b. Safe and effective

  c. Short recovery time

  d. Easy to administer

  e. All of the above


2. The first dentist to successfully use N2O for an extraction was Dr. Horace Well.

  a. True

  b. False


3. Synonyms for N2O include all of the following, except:

  a. Dinitrogen monoxide

  b. Hyponitrous acid anhydride

  c. Nitric monoxide

  d. Laughing gas


4. OSHA currently regulates exposure limits of nitrous oxide in clinical practice.

  a. True

  b. False


5. Nitrous oxide is an asphyxiant at high concentrations.

  a. True

  b. False


6. Tingling, numbness, difficulty in concentrating and interference in gait represent:

  a. Acute exposure

  b. Chronic exposure


7. Methods that are effective in controlling worker exposure to N2O, include:

  a. Process enclosure

  b. Local exhaust ventilation

  c. General dilution ventilation

  d. Personal protection equipment

  e. All of the above


8. The use of a Landauer Dosimeter badge is an active method of collecting a sampling to determine Nitrous oxide exposure for a clinician.

  a. True

  b. False


9. The anxiolytic effect of N2O is mediated by interaction with GABA-A receptors and closely resembles that of ethanol.

  a. True

  b. False


10. A __________ N2O to oxygen mixture is used as an adjunct to inhalation and IV general anesthesia.

  a. 20%-80%

  b. 30%-70%

  c. 40%-70%

  d. None of the above


11. In dentistry, N2O is typically used as a 25%-50% mixture with oxygen.

  a. True

  b. False


12. Indications for use of N2O in clinical dentistry include the following, except:

  a. A fearful, anxious, or obstreperous patient

  b. Patients in the first trimester of pregnancy.

  c. A patient with a gag reflex that interferes with care.

  d. A cooperative child undergoing a lengthy procedure.


13. Contraindications for use of N2O in patients include the following, except:

  a. Chronic obstructive pulmonary diseases.

  b. Severe emotional disturbances

  c. Treatment with bleomycin sulfate

  d. Methylenetetrahydrofolate reductase deficiency (B12)

  e. None of the above


14. Excessive exposure to N2O may occur as a result of leaks from the anesthetic delivery system during administration.

  a. True

  b. False


15. A positive pressure oxygen delivery system capable of administering ________ oxygen at 10 liters/ minute flow for at least _______ minutes must be available.

  a. > 70% - 30 mins

  b. > 80% - 30 mins

  c. > 90% - 30 mins

  d. > 90% - 60 mins

  e. > 100% - 60 mins


16. Use of a scavenging system is optional in an operatory with optimized room ventilation which is also digitally monitored.

  a. True

  b. False


17. Digital administration units deliver pure oxygen during the “flush” function by shutting off the nitrous oxide flow, as opposed to flow tube units, which only dilute the N2O delivered.

  a. True

  b. False


18. The _______ alarm function for oxygen depletion ensures patient safety.

  a. Oximeter

  b. Silenceable

  c. Non-silenceable

  d. Oxygen intake monitoring


19. Ideal sedation has been achieved when the patient states that he/she are feeling:

  a. feeling of warmth throughout the body.

  b. numbness of the hands or feet.

  c. numbness of the soft tissues of the oral cavity.

  d. a feeling of euphoria or heaviness in the extremities.

  e. all of the above.


20. The response of patients to commands during procedures during N2O anesthesia serves as a guide to their level of consciousness.

  a. True

  b. False


21. A reading on a pulse oximeters should not fall below:

  a. 70%

  b. 80%

  c. 90%

  d. 100%


22. Pressure / Volume toxicity is of concern with procedures prior to dental treatment by:

  a. Cardiologists

  b. Ophthalmologists

  c. Dermatologists

  d. Gastroenterologists


23. If a patient noted on their medical history the use of the antibiotic ___________, N2O should not be administered.

  a. Bleomycin

  b. Erythromycin

  c. Amoxicillin

  d. Bi-cillin K


24. Documentation of the patient’s N2O administration should include:

  a. percentage of N2O administered

  b. length of time the patient was sedated

  c. flow of gas during administration

  d. all of the above


25. Nitrous oxide exposure is risky for:

  a. Female dental assistants of reproduction age

  b. Patients in the first trimester of pregnancy

  c. Drug impaired patients

  d. All of the above