Background: Dense perineal block from epidural analgesia increases the risk of urinary catheterization in labour. Mobile epidurals using low-dose local anaesthetic in combination with opioid preserve maternal mobility and may reduce the risk of bladder dysfunction. We conducted a three-arm randomized controlled trial to compare high-dose epidural pain relief with two mobile epidural techniques.
Methods: A total of 1054 primparous women were randomized to receive high-dose bupivacaine, epidural analgesia (Control), combined spinal epidural (CSE), or low-dose infusion (LDI). The requirement for urinary catheterization during labour and postpartum was recorded. Both end points were pre-specified secondary trial outcomes. Women were evaluated by postnatal interview, when their bladder function had returned to normal.
Results: Relative to Control, more women who received mobile epidural techniques maintained the ability to void urine spontaneously at any time (Control 11%, CSE 31% and LDI 32%) and throughout labour (Control 3.7%, CSE 13% and LDI 14%), for both mobile techniques P<0.01. There was no difference in the requirement for catheterization after delivery. Women in the CSE group reported a more rapid return of normal voiding sensation, relative to high-dose Control (P=0.02).
Conclusions: Relative to conventional high-dose block, mobile epidural techniques encourage the retention of normal bladder function and reduce the risk of urinary catheterization in labour.