In those cases, the spread between the bid & ask goes to the market maker as compensation for making a market in a stock. For a liquid stock that is easy for the market maker to turn around and buy/sell to somebody else, the spread is small (narrow).
In cerebral hypoxia, sometimes only the oxygen supply is interrupted. Brain cells are extremely sensitive to a lack of oxygen. Some brain cells start dying less than 5 minutes after their oxygen supply disappears. As a result, brain hypoxia can rapidly cause severe brain damage or death.
brains of infants or children tend to withstand anoxia better than the adult brain, and. occasionally undergo remarkable recovery. For this reason, longer observation periods. are suggested for those 7 days to 2 months old (48 hours), 2 months to 1 year old (24. hours), and over 1 year old (12 to 24 hours).