Medical Gas Therapy

Goals of O2 Therapy

Relieve hypoxemiaPneumonia, V/Q mismatch

Decrease WOBAsthma, COPD

Decrease myocardial workMI, pulmonary edema

Effects of Hypoxemia

Peripheral vasodilationPatient feels warm

Pulmonary vasoconstrictionShunting, increased PVR

TachycardiaPrimary indication of hypoxemia

A 56 year old female patient is receiving oxygen at 1.5 L/min. via a pulsed-dose oxygen delivery system attached to a reservoir cannula. As you are doing your oxygen rounds, the patient complains of severe shortness of breath and states "she is not getting enough air". What would be your first immediate response at this time?

A.Attach the patient’s reservoir cannula to a thorpe tube flowmeter at 1.5 L/min.

B.Remove the cannula and verify the flowC.Troubleshoot the equipmentD.Increase the liter flow to 2 L/min.

The best way to check the accuracy of an air/oxygen proportioner is by using:

A.polarographic electrode analyzer

B.precision geisler tube analyzer

C.infrared absorption analyzer

D.teflon membrane analyzer

A patient with a laryngeal tumor is presently receiving 80/20% helium-oxygen by a nonrebreathing mask at 5 L/min. The patient is alert, but appears agitated. Vital signs indicate a pulse of 131/min, respirations at 30/min, and a blood pressure of 140/90 mm Hg. Which of the following is the most appropriate action to take?

A. Initiate sedation. B. Recommend changing to an F I O 2 of 1.0. C. Increase the gas flow to the mask. D. Administer racemic epinephrine.

ALL Equipment!

KnowWhen to use it.How to fit it.

Increase flow is the most common troubleshooting answer on the exam.

The physician has requested that you administer 80% helium and 20% oxygen mixture to a patient. Which of the following equipment would you need to administer the therapy?

I.    Air/oxygen proportioner II.    Venturi mask III.    Oxygen analyzer IV.    Non-rebreather maskA.IV onlyB.I and III onlyC.II onlyD.I, III and IV only

A patient is receiving oxygen via a Venturi mask at an FIO2 of 0.45. The nurse is complaining that the patient keeps removing the Venturi mask from his face. You would do which of the following at this time?

A.Tape the Venturi mask to the patient’s face

B.Restrain the patient C.Switch to a nasal cannula at 6 L/min. D.Intubate the patient orally

What is the least likely problem to watch for in a severe COPD patient receiving supplemental O2?

A.Pulmonary edema from O2 toxicityB.HypoventilationC.Retinopathy of prematurity (ROP)D.Hyperventilation

The recommended effective dose for Nitric Oxide Therapy is:

A. 0.5 – 1.5 ppm

B. 2 – 20 ppm

C. 80 – 150 ppm

D. 400 – 600 ppm

A patient is receiving 100% oxygen via an aerosol mask at 10 Lpm. Each time the patient inhales the aerosol mist disappears. The therapist has attempted to increase the flowrate without success. Which of the following should the therapist recommend?

A. Switch to a tandem set-up

B. Change to a non-rebreather

C. Decrease the FiO2 to 75%

D. Change to assisted ventilation with 100% oxygen

What is the approximate total flow that would be delivered from a 40% air-entrainment mask receiving 12 L/min of oxygen?

A. 12 L/min B. 48 L/min C. 52 L/min D. 72 L/min

Air: oxygen entrainment ratios 28%

Ratio = 10:1 Factor = 11 35%

Ratio = 4.3:1 Factor = 5.3 Just flip it around!

40%Ratio = 3:1 Factor = 4Just flip it around!

60%Ratio = 1:1 Factor = 2

A patient has just been admitted through the emergency department with suspected CO poisoning. The physician wants her to receive the highest possible O2 percentage. What would you recommend?

A. Continuous positive airway pressure mask at 5

cmH2O and 40% O2B. Simple mask at 6 L/min flowC.Face tent at 8 L/min flowD.Nonrebreather mask with enough flow to keep the

reservoir bag at least two-thirds full

A patient with chronic hypercapnia is to receive oxygen at home by nasal cannula at 2 L/min. The respiratory therapist should advise the patient to ensure the oxygen flow does not exceed 2 L/min because excessive oxygenation may

A. dry secretions. B. cause oxygen toxicity. C. trigger retinopathy. D. depress breathing.

You are making general rounds in the hospital when you find a patient whose reservoir tuning has fallen off his 40% Brigg’s adapter. This would result in which of the following?

A.Increased inspired O2B.Increased inspired CO2C.Decreased inspired CO2D.Decreased inspired O2

A patient is receiving oxygen by a nonrebreathing mask. The reservoir bag collapses during inspiration. The respiratory therapist should

A. increase the oxygen liter flow by 5 L/min. B. adjust the flow until the reservoir bag remains partially inflated at end-inspiration. C. remove leaflet valves from exhalation ports. D. remove the one-way valve between the reservoir bag and the mask.

The risks of O2 therapy include all of the following EXCEPT:

A.Pulmonary O2 toxicityB.Denitrogen absorption atelectasisC.O2 induced hyperventilationD.ROP

A respiratory therapist has initiated oxygen therapy with a nasal cannula. In addition to a signature and credentials, which of the following is the best example of appropriate documentation?

A. nasal cannula placed on patient, HR=96, SpO 2 =92%,

RR=22 B. 12/6/03, 2 L/min oxygen placed on patient at 0830 C. 0830, nasal cannula at 2 L/min, temp=101, HR=96, RR=22, BP=150/80 D. 12/6/03, 0830, nasal cannula started at 2 L/min, SpO 2 =92%, RR=22, HR=96

An air-entrainment mask will deliver an F I O 2 higher than intended if

A. the flow is set too high.

B. nebulized water is being added through the

air-entrainment ports.

C. corrugated tubing was added between the air-

entrainment adapter and mask.

D. the air-entrainment ports have been blocked.

You are working with an intubated patient who is mechanically ventilated. The O2 analyzer is a galvanic fuel-cell type. Every time the patient’s airway pressure fluctuates during a mechanical breath, the O2 percentage goes up and then down. This could be caused by:

A. Plugged capillary lineB. Dry analyzer chamberC.Variable pressure against analyzer probeD.Exhausted supply of chemical reactant

Which of the following oxygen administration devices is capable of meeting and/or exceeding a patient's inspiratory flow?

A. air-entrainment mask B. nasal cannula C. nonrebreathing mask D. reservoir cannula

A physician orders an F I O 2 of 0.40 for a premature infant in an incubator. Which of the following delivery devices should the respiratory therapist select?

A. air-entrainment mask B. oxygen hood C. infant nasal cannula D. simple mask

Your patient is wearing a partial-rebreathing mask. The reservoir bag almost totally collapses during her inspiration. You would do which of the following?

A.Tell the patient to breath more slowly

B.Put a nasal cannula on the patient

C.Tell the patient to breath more rapidly

D.Increase the O2 flow

A patient is receiving 80%/20% heliox using a standard oxygen flowmeter. Which of the following is the correction factor to determine the accurate flow?

A. 1.4 B. 1.6 C. 1.8 D. 2.4

Heliox conversion factors: 80% He / 20% O2

1.8 70% He / 30% O2

1.6

What O2 delivery device would you recommend for a patient who has a variable respiratory rate, I:E ratio, and Vt?

A.Nasal cannula

B.Air-entrainment mask

C.Simple O2 mask

D.Face tent

A patient with COPD is receiving oxygen, 2 L/min by nasal cannula, at home. The patient's SpO 2 is usually 90%. When visiting the patient, the respiratory therapist finds the oxygen set at 4 L/min, the patient lethargic, and his oxygen saturation is 95%. Which of the following should the therapist do immediately?

A. Obtain a blood gas sample and notify the physician. B. Contact the physician and request hospital admission. C. Change the oxygen flow to 2 L/min and observe the patient. D. Discontinue oxygen until the patient's mental status improves.

The physician asks you which O2 delivery device would be

best for a patient who needs about 75% O2. You would

recommend which of the following?

A. Nonrebreathing mask

B. Face tent

C.Air-entrainment mask

D.Simple O2 mask

An 18-month-old infant is to receive 30% oxygen by mist tent. While performing a routine equipment check, the respiratory therapist notices the oxygen analyzer inside the tent reads 25%. After calibrating the oxygen analyzer, it still indicates 25%. The therapist should

A. change oxygen analyzers. B. check the air inlet for an obstruction. C. check the oxygen inlet for an obstruction. D. add sterile water to the nebulizer reservoir.

A patient has a nasal cannula and needs to be transported on a stretcher. The E-size O2 cylinder will need to be laid flat under the stretcher. What flow meter would you recommend using?

A.Backpressure-compensated ThorpB.Nonbackpressure-compensated ThorpC.BourdonD.Backpressure-compensated kinetic

The respiratory therapist is calibrating several gas measurement devices in the ICU. Air should be used to zero calibrate which of the following?

A. capnograph B. nitrogen analyzer C. Clark electrode D. oxygen analyzer

Which of the following devices should be used to effectively deliver a 70% helium/30% oxygen mixture to a patient?

A. simple mask B. oxygen hoodC. nasal cannula D. nonrebreathing mask

What is the duration of flow of an E-cylinder with 1700 psig that is running at 5 L/min?

A.0.9 hrB.1.6 hrC.7.7 hrD.13.7 hr

Duration of flow Duration = Gauge pressure x tank factor

liter flow Tank Factors:

E cylinder = 0.28 L/psi (0.3)H cylinder = 3.14 L/psi (3.0)

Full cylinder = 2200 psi

The respiratory therapist is using an oxygen calibrated flowmeter to administer a gas mixture of 70% helium and 30% oxygen. To deliver a flow of 8 L/min of the gas mixture to the patient, the therapist should set the oxygen flowmeter to

A.   3 L/min. B.   5 L/min. C.   8 L/min. D. 11 L/min.

You are doing quality assurance on the department’s flowmeters. After plugging in a backpressure-compensated Thorpe flowmeter, you set the flow at 10 L/min. The flowmeter outlet is partially and then completely occluded obstructed. You would expect to see the following:

A. The float will stay at the 10 L/min markB. The float will move upward in the flowmeterC.The float will move upward and then downward in the

flowmeterD.The float will move downward and then drop to the

bottom of the flowmeter showing zero flow

While checking pressures at several oxygen outlets, the respiratory therapist notes readings near 26 psig. The hospital uses a cylinder bank bulk oxygen system. Which of the following should the therapist do first?

A. Check the bank supply lines for a leak. B. Switch to the back-up bank of cylinders. C. This situation requires no intervention. D. Change patients who are receiving oxygen to E cylinders.

The End

Your patient is wearing a face tent because of recent facial surgery. It is set at 35% O2. The nurse moves the patient from an upright to a supine position on the bed. What effect will this have on her respiratory status?

A.Increased VtB.Increased inspired O2C.Increased inspired CO2D.Decreased inspired O2

Initially the O2 percentage found in an O2 tent of a two-year-old child was found to be stable at the ordered 35%. Now less than that is found. All of the following should be tried EXCEPT:

A. Add an additional flowmeter and run them both at flushB. Keep the tent canopy tightly tucked under the mattressC.Keep the canopy flaps closed when the child is not

receiving nursing careD.Check the analyzer for proper function

An E-cylinder of O2 needs to be prepared to transport a patient. You would look for a regulator with which pinhole locations?

A.1-5B.2-6C.3-5D.2-5