Randomized Controlled Trial
Epidural analgesia during labor--0.5% lidocaine with fentanyl vs. 0.08% ropivacaine with fentanyl.
Middle East J Anaesthesiol. 2010 Feb 1;20(4):521-7.
Randomized Controlled Trial
Ropivacaine, 0.1%, plus sufentanil, 0.5 microg/ml, versus bupivacaine, 0.1%, plus sufentanil, 0.5 microg/ml, using patient-controlled epidural analgesia for labor: a double-blind comparison.
Anesthesiology. 2000 Jun 1;92(6):1588-93.
Randomized Controlled Trial
Comparison of epidural tramadol-ropivacaine and fentanyl-ropivacaine for labor analgesia: a prospective randomized study.
Ups. J. Med. Sci. 2011 Nov 1;116(4):252-7.