Obstructive Hypopnea, or just, Hypopnea basically means shallow breathing. A hypopnea is
when a person is actively trying to breathe, but there is an obstruction that is preventing air from
getting into the lungs. This differs from an Obstructive Apnea in that some air is able to get
through. The breathing that is allowed is so low, that the effect is the same as an Obstructive
Apnea. The obstruction is caused by some type of tissue blocking the airway.
Eventually the blood oxygen level (SpO2) drops, heart rate spikes, and the patient will wake
gasping for air often with a snore or a snort. Often the awakening isn't remembered and they go
right back to sleep only to repeat this cycle throughout the night. This can be successfully
treated with CPAP.
To the right are several examples of
Obstructive Hypopneas (hypopneas or
OSH) The belts that are around the chest
and abdomen are still moving indicating
they are trying to breathe. "Flow" is the
sensor that shows breathing. You can see
that this patient is still breathing, but that it is
less that periods where the patient wakes.
The C3,C4,O1, and O2 signals speed up,
and the Chin electrodes (EMG2-EMG3)
increase. The breathing also resumes at
this point. The oxygen level drops by 4%
It is fair to say that a Hypopnea is just a
lesser form of an Apnea, where breathing
stops completely. Please don't think that
this diminishes its severity. These still
prevent oxygenation of your brain and
heart, which kills cells, causes your heart
rate to increase, and causes you to wake
feeling extremely tired.
The images to the right show clear
Hypopneas. These are all 2 minute
examples, so you can see how each
hypopnea develops and can cause
tremendous disruptions to sleep
consolidation. Click on the image for a
faster loading, but grainy picture. Or click
on the Blue icons for the same picture in a
much higher resolution. May take 10-30
seconds to completely load depending on
your connection speed.