sleeping Flashcards
define apnoea
Apnoea – the cessation of breathing.
what are the 2 unparalysed muscles in REM?
During REM, only 2 unparalysed muscles are diaphragm and eye muscles
what is sleep measured using?
Sleep is measured using an electroencephalogram (EEG) and awake gives a high frequency and a low voltage.
During sleep, which control is eliminated?
During sleep, emotional and voluntary/behavioural control is eliminated. Only reflex/autonomic control is dominant.
§ NO cortical control when in deep sleep.
where does voluntary breathing come from?
Voluntary breathing (when awake) comes from the motor homunculus (located in the brain between motor areas for the shoulder and the trunk).
where does automatic control of breathing come from?
The respiratory neurones are found on the rostral-ventral-lateral medullary surface.
§ The cluster of respiratory nuclei is named the Pre-Botzinger Complex.
o These neurones reciprocally inhibit each other (when one fires, the other stops) which allows breathing to take place.
where does the emotional control of breathing come from?
We can measure breathing using a lesion deficit model.
o Using patient’s that have had a bleed in the brain, we can understand more about how the respiratory neurones are connected in the body.
§ Locked-in Syndrome – patients that have had a bleed in the superior brainstem and so have preserved sensory functions but no motor output (except oculomotor control).
o This syndrome proved that the limbic system (emotional) had an affect on breathing rate as they could still alter their RR with emotions.
what is Central Sleep Apnoea?
when the CO2 levels do not raise above the apnoeic threshold and so breathing stops.
what happens when you sleep?
When you’re asleep, the following happens:
o The muscles relax.
-Genioglossus and Levator Palatini muscles.
o Positive extra-luminal pressure is present (gravity, adipose weight).
o Negative intra-luminal pressure is present.
-These can predispose you to airway collapse which is also known as obstructive sleep apnoea (OSA).
-When a breath is taken in, the uvula blocks the airway.
-A recessed jaw can also predispose someone to OSA
what happens in obstructive sleep apnoea
- Patient falls asleep and lose UA muscle function.
a. Not to do with respiratory control, there is a mechanical obstruction. - No breathing so O2 levels fall and CO2 levels rise.
- Eventually, either the hypoxia or hypercapnia wakes you up (chemosensitivity is still normal).
- Cycle begins again.
difference between central and obstructive sleep apnoea
In obstructive sleep apnoea, there may be no airflow but they are still TRYING to breathe so there is thoracic and abdominal effort.
§ Central Sleep Apnoea is due to changes in sensitivity of the chemoreceptors while obstructive sleep apnoea has healthy chemoreceptors.
heart failure patient are likely to suffer from?
central sleep apnoea
