Last week, the Los Angeles medical examiner revealed a surprising detail in actress Carrie Fisher’s autopsy: sleep apnea contributed to her death. Sleep apnea is when a person stops breathing while they’re sleeping for 10 seconds, a minute, or even longer. This may happen repeatedly throughout the night causing oxygen-blood levels to dip dangerously low while putting a strain on the heart. The most common type is obstructive sleep apnea which is caused by upper throat muscles relaxing. According to the National Sleep Foundation more 18 million Americans are affected by this type of sleep apnea. The most effective way to treat sleep apnea is through the use of a continuous positive airway pressure, or CPAP, machine.