Flashcards in Test #2 Sleep Apnea ARTICLES - Rude man Deck (21):
Define obstructive sleep apnea.
repetitive partial or complete obstruction of the upper airway and is characterized by episodes of cessation of breathing during sleep lasting for more than 10 seconds
What is considered the "gold standard" for diagnosing sleep apnea?
(aka - a sleep study)
The apnea hypopnea index (AHI) is the number of episodes of apnea or hypopnea per hour during sleep. What is the accepted minimal AHI for a diagnosis of OSA?
AHI of 10, plus symptoms of excessive daytime sleepiness.
List the patient populations at risk for developing OSA. (8)
- treatment resistant HTN
- the acute phase of stroke
Propofol can cause a dose-dependent inhibition of what muscle?
the genioglossus muscle (keeps the tongue anterior), resulting in greater collapsibility of the upper airway
Opioids can impair respiratory function by direct action on the respiratory motor activity of what two nerves?
Mechanically, when does an upper airway obstruction occur? (vague question...sorry)
when the negative pressure generated by the inspiratory muscles exceeds the capacity of the upper airway dilator muscles to maintain airway patency
Investigation of the actions of sedatives, anesthetics, and analgesics points to the ________ as a primary site of obstruction after anesthesia.
So, the three things that occur with obstructive sleep apnea...
- increased airway collapsibility due to an increase in the critical closing pressure
- loss of tonic activity in pharyngeal muscle
- failure of the phasic activation of upper airway muscles before diaphragmatic activity
Post-op complications associated with OSA. (6)
- respiratory complications
- sustained arrhythmias / conduction disturbances
- pulmonary edema
What are two questionnaire based screening tools for OSA?
The Berlin Questionnaire
Which screening tool is ideal for pre-op screening?
What does STOP-BANG stand for? (8)
- do you SNORE loudly
- do you feel TIRED during the daytime
- has anyone OBSERVED that you stop breathing during sleep
- do you have a history of high blood PRESSURE
- BMI > 35
- AGE > 50
- NECK circumference > 40cm
- male GENDER
What is the sensitivity of the STOP-BANG questionnaire?
What are some medications that can be used for post-op pain control that are not opioids and can help prevent airway obstruction?
(novel approaches - ketamine, clonidine, or gabapentin)
ASA guidelines recommend what patient position for extubation in OSA patients?
Define central sleep apnea.
a temporary failure of the generation of breathing rhythm
(polysomnographically, central sleep apnea is recognized by the absence of naso-oral airflow and by thoracoabdominal excursions that reflect the failure of activation of inspiratory pump muscles)
Why does it occur?
it occurs when the level of PCO2 falls below the apneic threshold, a PCO2 below which breathing ceases
(so they breath really fast, blow off a bunch of CO2, then stop breathing so they can build it back up again)
Episodes of central sleep apnea associated with periodic breathing can occur in what three instances?
- in severe CHF with systolic dysfunction
- at high altitude
- in an idiopathic form
What is the mechanism of action of acetazolamide in relation to central sleep apnea?
its related to metabolic acidosis, which stimulates chemoreceptors.
(so, the medication increases the amount of CO2 and prevents it from getting too low from the rapid breathing)