Sleep apnea can be mild or severe. The level of severity depends on the number of apnea episodes. Each episode goes through <I>muscle collapse</I>, <I>breathing interruption</I> and then a brief <I>awakening</I>. This could happen 20 to 30 times or more each hour and all night long! Every interruption of breathing usually lasts 10 to 20 seconds, but could be as long as 60 seconds.