Humidity & Aerosol

1. Humidity & Aerosol

2. A gas is saturated with 100% relative humidity at 32.2 ° C (90 ° F). As the gas cools to 26.7 ° C (80 ° F), the relative humidity will A. increase by 10%. B. remain 100% and excess water will rain out. C. decrease as a result of cooling of the gas. D. decrease as water condenses.

3. A 4-year-old asthma patient is about to be discharged and needs to take an inhaled bronchodilator medication at home. What device would you recommend be used? • SPAG • DPI • DPI with holding chamber • MDI with holding chamber

4. A 2-year old child recently diagnosed with laryngotracheobronchitis requires the administration of 40% oxygen. What is the most appropriate method for delivering the oxygen? • Oxyhood connected to a blender set at 40% and 10 L/min • Heated aerosol mask set at 15 L/min and 40% • Venturi mask set at40% • Aerosol tent at 40%

5. A heat moisture exchanger is most appropriate for a patient A. who is receiving noninvasive positive pressure ventilation. B. with ARDS who is receiving mechanical ventilation. C. who is receiving mechanical ventilation in the PACU. D. with a bronchopleural fistula who is receiving mechanical ventilation.

6. A comatose patient is intubated and receiving 35% O2 with aerosol through a T-adaptor. While watching the patient breathe, you notice that during each inspiration the mist disappears from the downstream end of the T-adapter. What would you recommend? • All 100 ml of aerosol tubing as a reservoir on the T adaptor • Change the O2 to 30% and increase the flow • Change the O2 to 40% and decrease the flow • Tell the patient not to breathe so deeply

7. What is a major advantage of a wick humidifier compared with other types of humidifiers? A. Operation is most efficient at room temperature. B. Both molecular and particulate water are produced. C. A relative humidity of 100% is easily produced. D. A baffle is not needed to produce the desired humidity.

8. A physician calls you to evaluate a 40-year-old patient with bronchitis and make a recommendation for an aerosol delivery system. The patient’s breath sounds indicate the presence of large airway secretions. Despite a good cough effort the patient has difficulty expectorating them. What would you recommend ? • Handheld nebulizer with 3 cc of normal saline every 4 hours • Place the patient into a mist tent • Start a continuous ultrasonic nebulizer to an aerosol mask • Start a Cascade-type humidifier at 95°F to an aerosol mask

9. Which of the following is the major function of the baffle in a nebulizer? A. entraining water from the capillary tube B. providing aerosol particles that are consistently small C. mixing aerosol particles with the main gas flow D. promoting laminar inspiratory flow

10. A patient’s humidity deficit is going to be the smallest under which of the following conditions: • Breathing regular hospital room air at 72° f and 40% relative humidity • Breathing outside air at 80° F and 50% relative humidity • Breathing 6 L/min of O2 through a nasal cannula running through an unheated bubble humudufier • Breathing 40% O2 through a wick type humidifier at 95° F to an aerosol mask

11. Which of the following devices can provide the greatest total fluid output? A. ultrasonic nebulizer B. large volume jet nebulizer C. bubble humidifier D. heated Cascade humidifier

12. Which of the following is the most probable cause of insufficient aerosol output in a mist tent? A. decreased temperature within the canopy B. compressor switch in the off position C. overfilled condensate bottle D. a clogged capillary tube in the nebulizer

13. The respiratory therapist is called to check an oxyhood in the NICU. The unit is using a large volume nebulizer and an air/oxygen blender with a flowmeter. The therapist notes the pressure pop-off valve on the nebulizer is chattering. Which of the following actions is required? A. Increase the flowmeter from 5 to 8 L/min. B. Check the tubing to the oxyhood for an obstruction. C. Reposition the capillary tube in the nebulizer. D. Tighten the high pressure supply line connections to the blender.

14. Your patient has a temperature of 98.6° F. To saturate the inhaled air, how much absolute humidity must be provided by the humidifier? • 37° C • 47 mmHg • 760 mmHg • 44 mg/L

15. A patient is receiving an F I O 2 of 0.40 by a heated nebulizer connected to a T-piece. Five hours later, the F I O 2 analyzed at the nebulizer side of the T-piece is 0.45. Which of the following should the respiratory therapist do to correct the problem? A. Clear the nebulizer jet. B. Replace the nebulizer. C. Empty the condensate from the aerosol tubing. D. Increase the flow to the nebulizer.

16. The End

17. To help prepare a patient for a laryngoscopy procedure, the physician has ordered her to inhale nebulized lidocaine (Xylocaine). You would select a nebulizer that generates what size particles? • 1 to 3 micrometers • 2 to 5 micrometers • 5 to 7 micrometers • 10 micrometers or larger

18. An ultrasonic nebulizer would be recommended for aerosol therapy for the following reason: • It delivers a wide variety of aerosol droplets • Its aerosol droplets are between 10 and 20 micrometers in diameter • It delivers uniform aerosol droplets of about 4 - 6 micrometers in diameter • It can be used to nebulize bland aerosols and liquid medications into an aerosol

19. Your patient has an endotracheal tube. Which of the following devices would be the least effective in reducing this patient’s humidity deficit? • Wick-type humidifier set at 35° C • Cascade –type humidifer set at 35° • Unheated bubble humidifier • Ultrasonic humidifier

20. Your heated humidifier unit has a water reservoir temperature of 40°C. The humidified gas is traveling through large bore tubing to the patient. Which of the following statements are true? • Condensation will occur • The gas will warm and expand as it travels to the patient • The gas will remain saturated • The relative humidity will decrease • The relative humidity will increase • A. I and III • B. IV • C. I and V • D. I and IV