Oxygen Administration
What is the normal flow range for a nasal cannula?
1–6 L/min
What does “total flow” mean when discussing an air-entrainment system?
The total amount of gas delivered to the patient, including oxygen plus entrained room air.
What normal breath sound is heard over most peripheral lung fields?
Vesicular breath sounds
What is the primary indication for airway suctioning?
The presence of secretions that the patient cannot adequately clear.
An oropharyngeal airway should generally be used only in what type of patient?
An unconscious patient without an intact gag reflex
A patient needs approximately 40% oxygen using a simple oxygen delivery device. Which device would be appropriate?
A simple mask or appropriately set air-entrainment mask, depending on the desired precision.
A device has an air-to-oxygen ratio of 3:1 and oxygen is flowing at 10 L/min. What is the total flow?
40 L/min
What adventitious breath sound is commonly associated with narrowed airways such as asthma?
Wheezing
Should suction be applied while inserting the suction catheter?
No. Suction is applied while withdrawing the catheter.
How do you estimate the proper size of an oropharyngeal airway?
Measure from the corner of the mouth to the angle of the jaw/mandible.
What is the minimum recommended flow for a simple oxygen mask to prevent rebreathing of carbon dioxide?
5 L/min
A patient has a minute ventilation of 10 L/min. During inspiration, the inspiratory phase occupies one-third of the respiratory cycle. Approximately what minimum flow must a device provide to meet the patient's inspiratory demand?
About 30 L/min
A patient has coarse, low-pitched breath sounds that may improve after coughing. What breath sound is being described?
Rhonchi
Approximately how long should one suction attempt generally last?
No more than about 10–15 seconds
What is one advantage of a nasopharyngeal airway over an oropharyngeal airway?
It can often be tolerated by a conscious or semiconscious patient with an intact gag reflex.
Your patient has an SpO₂ of 76% and is in severe respiratory distress. Which commonly used oxygen device can provide the highest oxygen concentration without positive-pressure ventilation?
Nonrebreather mask
A 28% air-entrainment mask has an air-to-oxygen ratio of approximately 10:1. If the oxygen flow is 6 L/min, what is the approximate total flow?
66 L/min
A patient has an RR of 32/min, nasal flaring, intercostal retractions, and is speaking only two or three words at a time. What do these findings indicate?
Significant respiratory distress/increased work of breathing
During suctioning, your patient's heart rate drops from 92/min to 48/min. What should you do first?
Immediately stop suctioning and oxygenate the patient.
What is the purpose of the cuff on an endotracheal tube?
To seal the airway, allow effective positive-pressure ventilation, and reduce aspiration of material around the tube.
A nonrebreather mask is running at 10 L/min, but the reservoir bag completely collapses during inspiration. What should you do?
Increase the oxygen flow until the reservoir bag remains at least partially inflated during inspiration.
A patient using an air-entrainment mask has a respiratory rate of 34/min and appears to be pulling room air around the mask. What is the likely problem?
The total flow from the device is not meeting the patient's inspiratory flow demand.
You assess a patient and find absent breath sounds over the entire left chest with sudden severe dyspnea. What serious condition should be considered?
Pneumothorax
What is the most likely reason a patient becomes bradycardic during airway suctioning?
Vagal stimulation and/or hypoxemia
Immediately after endotracheal intubation, what is considered the most reliable bedside method for confirming placement in the trachea?
Continuous waveform capnography/end-tidal CO₂ detection