7Tan JA, Ho KM. Use of dexmedetomidine as a sedative and analgesic agent in critically ill adult patients: a meta -analysis[ J]. Intensive Care Med,2010,36(6) :926 -939.
8Johnson MH. How does distraction work in the manage of paine[ J ]. Current Pain and Headache Reports,2005,9(2) :90 -95.