After decades of poking and prodding patients at all hours, hospitals are waking up to the notion that sick people need sleep. WakeMed Health & Hospitals now observes nightly quiet hours at its facilities starting at 8 p.m. Several intensive care units at hospitals across the region offer daily quiet time. It's a welcome peace amid the persistent activity in the ICU, where nurses or other medical staff sometimes come to the bedside as often as every 20 minutes.