Yet humans are rarely attacked by a shark, while millions of sharks are killed by humans. Some populations of shark species, such as the shortspine spurdog, may have dropped by 95 percent. The sharksâ population decline has a ripple effect â throwing entire marine ecosystems out of balance.
Quick Answer. A normal blood oxygen level during sleep is approximately 94 to 98 percent, according to Sleep Apnea Guide. Levels below 90 percent oxygen saturation are dangerous to the human body. The human brain can only survive four minutes without oxygen before cell death occurs.
Normal and Abnormal Blood Oxygen Levels During Sleep. Low sleep apnea oxygen level is a sign that your treatment for sleep apnea is not effective. Patients with breathing problems during sleep (sleep apnea, COPD) often have low oxygen levels in their blood. A normal blood oxygen level should be 94% to 98% .However, as a result of not breathing for 30 seconds or more during sleep, your sleep apnea oxygen level would drop to 80% or less. Keep in mind that anything below 90% oxygen level is dangerous to your body and require intervention.ormal and Abnormal Blood Oxygen Levels During Sleep. Low sleep apnea oxygen level is a sign that your treatment for sleep apnea is not effective. Patients with breathing problems during sleep (sleep apnea, COPD) often have low oxygen levels in their blood. A normal blood oxygen level should be 94% to 98% .