1Ulker B,Erhay RH,Serin S. Comparison of spinal,low- dese spinal and epidural anesthesia with ropivacaine plus fentanyl for transurethral surgical procedures[J]. Kaohsiung Journal of Medical Sciences, 2010,26(4) : 167-174.
2Fleet J,Jones M,Belan I. Non-axial administration of fen- tanyl in childbirth: a review of the efficacy and safety of fentanyl formother and neonate[J]. Midwifery, 2011,27( 1 ) : e106.
