If you have a patient with acute O2 desat, one of the things you should consider is: do they have thick secretions? Do they have poor air movement? Could they have a mucus plug?
Abundant thick airway secretions may become impacted in the lower airways, causing obstruction and atelectasis. Mucus plug may cause lung collapse .
If the patient is on a ventilator, you may be able to detect excessive airway secretions on the flow-volume loop, which will show a sawtooth pattern representing intermittent changes in airway resistance.
How can you protect against mucus plugs? Give patients humidified O2. Do pulmonary toilet, with frequent airway suctioning. Give medications like glycopyrrolate, which can thin secretions.