2Takiguchi T, Okano T, Egawa H et al .The effect of epidural saline infection on analgesic level during combined spinal and epidural anesthesia assessed clinically and myelographically. Anesth Analg, 1997,85:1097-1100.
3Rudolf Stienstra, Ban Z. R. Dilrosun - Alhadi,et al. The Edidural"Topup"in Comdined Spinal - Epidural Anesthesia: The Effect of Volume Versus Dose. Anesthesia& Anagesia, 1999,88:810 ~ 814
4Litwin AA, Joseph L. Mode of delivery following labor epidural analgesia : Influence of ropivacaine and bupivacaine . AANAJ ,2001,69(4) : 259.
5Angelo R. New techniqu, for labor analgesia: PCEA and CSE. Clin Obstet Gynecol, 2003, 46(3): 623.
6Scott KD, Berkowitz G, Klaus M et al .A comparative of intermitten and continous support during labor: A meta- analysis. Am J Obster Gynecol, 1999, 180(5):1 054.
7Ferrant FM,Lu L,Jamisoa SB et al .Patient controlled epidural analgesia: demand dosing. Anesth Analg, 1991, 73 : 547.
8Colis RE, Plato PS, Morgan BM. Comparison of midwife top - ups,continuous infusion and patient - controlled epidural analgesia for mainraining mobility after a low - dose combined spinal - epidural. Br J Anaesth, 1999, 82(2):233.