Mixed Sleep Apnea, or Mixed Apnea (MSA) is a hybrid of an Obstructive Apnea, and a Central Apnea. These typically start out as Central Apneas where all respiratory channels are flat. Then the Chest and Abdominal belts start moving making it look like an Obstructive Apnea. So this starts out like the patient isn’t even trying to breath, then when they do try to breathe, the airway is blocked.
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.
Some people confuse “Mixed Apnea” with Complex Sleep Apnea. They are not the same. Mixed apneas are treated the same as Obstructive Sleep Apnea, but it is a red flag that Complex Sleep Apnea may emerge with the use of CPAP Therapy (Continuous Positive Airway Pressure).
Above are a couple examples of Mixed Sleep Apneas. The belts that are around the chest and abdomen initially don’t move, indicating they aren’t trying to breathe. “Flow” is the sensor that shows breathing, which there isn’t any throughout the Mixed Apnea. Eventually the Chest and Abdomen belts start moving indicating the patient is now trying to inhale. 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% or greater.