Chapter 1 Pre & Post Test Questions Oxygen and Medical Gas Therapy

An 80:20 mixture of helium/O₂ running through an O₂ flowmeter at 6 L/min is delivering how much flow to the patient?

1.8 x 6 = 10.8 L/min

Given the following data, what is the patient's total arterial O2 content? pH 7.41 PaCoO2 37 mmHg PaO2 88 mmHg HCO3- 26 mEq/l SaO2 95% Hb 14 g/dL A. 12 mL/dL B. 14 mL/dL C. 16 mL/dL D. 18 mL/dL

18 mL/dL

The physicain has ordered O2 to be set up on a patient who has a spontaneous tidal volume of 500 L and an inspiratory time of 1 second. Which of the following O2 delievery devices will deliever a flow that meets or exceeds this patient;s inspriatory flow? A. 35% air entrainment mask at 6 L/min B. 60% aerosol mask at 12 L/min C. Nonrebreather mask at 15 L/min D. Simple O2 mask at 10L/min

35% air entrainment mask at 6 L/min

The respiratory therapist receives an order to set up a moderate level of O2 on a patient who arives in the ED breathing at a rate of 35 breaths/min. Which of the following O2 delivery devices is most appropiate to use in this situation? A. Simple O2 mask at 10 L/min B. nasal cannula at 4 L/ min C. Nonrebrathing mask at 15 L/min D. Air entrainment mask at 40% O2

Air-entrainment mask at 40% O2

Calculate total O2 content, given the following ABG test result: pH 7.36 PaCO2 40 mmHg PaO2 82 mmHg SaO2 96% Hb 13 g/dL

1.34 x 13 x 0.96 = 16.7 0.003 x 82 = 0.25 / 16.95 OR 17 g/dL

List 5 conditions that affect the accuracy of pulse oximeters.

poor perfusion severe anemia hypotension elevated HbCO level direct light phototherapy fluorescent light sources nail polish dark skin pigments

How does water in the aerosol tubing of a mask affect the delivered FiO2?

Increases FiO2

While making O2 rounds, you discover the 6 in reservoir tubing on a 60% T - piece set up as fallen off. What may result from this situation? 1. The FiO2 could descrease 2. the total flow to the patient could increase 3. More room air entrainment could occur

1 & 3 only

A patient is recieving O2 from an E cylinder at 4L/min through a nasal cannula. The cylinder pressure is 1900 pig. How long will the cylinder run until its empty? A. 47 min B. 1.7 hours C. 2.2 hours D. 3.6 hours

2.2 hours (1900 / 4) x 0.3

A patient is using a 30% air-entrainment mask at an O2 flow of 5 L/min. The total flow delievered by this device is which of the following? A. 36 L/min B. 45 L/min C. 54 L/min D. 60 L/min

45 L/min

The physican orders O2 therapy for a patient with a Vt of 400 mL and an inspiratory time of 0.5 s. What flow must the mask deliver to meet the patient;s inspiratory flow demands.

48 L/min Vt / inspiratory time= 0.4L/ 0.5s = (0.8 L/s x60) = 48/min

The following blood gas levels have been obtained from a patient using a 60% aerosol mask. pH - 7.47 PaCO2 - 31 mmHg PaO2 - 58 mmHg What should the respiratory therapist recommend at this time? A. Place the patient on CPAP B. Increase the O2 to 70% C. Intubate and place the patient on mechanical ventilation D. change to a nonrebrathing mask

Place the patient on CPAP

List 5 indication for the use of hyperbaric O2 therapy.

CO poisoning cyanide poisoning decompression sickness gas grene gas embolism

What is the primary benefit of using a reservoir cannula?

Conserves O2 by storing it in the reservoir

List the three ventilatory criteria that should be met by patients recieving O2 from a low flow device.

Consistant ventilator pattern, Vt 300 to 700 mL, respiratory rate of less than 25 / min

Give examples of three low flow O2 delivery devices.

Nasal cannula, simple O2 mask, partial rebreathing mask

A patient with carbon monoxide (CO) poisoning can best be treated with which of the following therapies? A. Nasal cannula at 6 L/min B. Simple O2 mask at 10 L/min C. CPAP and 60% O2 D. Nonrebrathing mask

Nonrebreathing masks

Four examples of high flow O2 delivery devices

air - entrainment mask aerosol mask T-peice (briggs adapter) face tent traceostomy collar

Calculate how long an "E" cylinder with 1900 psig will run at 5 L/min.

(1900 x 0.28) / 5 = 532 / 5 = 106 minutes = 1hr 46 minutes

What is the total flow delivered by an aerosol mask on 60% O2, running at 12 L/min?

60% (1:1 ratio) 1+1 = 2 2 x 12= 24

List the air/O2 ratios for 60% O2, 40% O2, 35% O2, 30% O2, 24% O2.

60% - 1:1 40% - 3:1 35% - 5:1 30% - 8:1 24%- 24:1`

After setting up a nonrebreather mask on a patient at a flow of 10L/min, the reservior bag collapses before the patient finishes inspiring. The respiratory therapist should do which of following? A. Change to a simple O2 mask at a flow of 10 L/min. B. Remove the one-way valve from the exhalation port C. Place the the patient on continous positive airway (CPAP) D. Increase the flow to 15L/min

Increase the flow to 15 L/min

A severe COPD patient arrives in the ED on a 2 L/min nasal cannula. Arterial bood gas results follow: pH 7.32 PaCo2 67 mmHg PaO2 62 mmHg HCO3 38 mEq/L Which of the following is the most appropriate recommendation? A. Increase the liter flow to 4 L/min B. Miantain the current O2 level C. Institute noninvasive ventilation D. Place on a nonrebreathing mask at 12 L/min

Maintain the current O2 level.