Outcomes of Neuraxial Anesthetic Technique on the Trial of Labor After Cesarean (TOLAC)
Condition: Labor Pain; Complications; Cesarean Section; Pregnancy
MeSH terms: Labor Pain
Study type: Interventional
Phase: Phase 4

Summary: 
      To compare the effects of epidural versus combined spinal and epidural (CSE) anesthesia on
      the success of Trial of Labor After Cesarean (TOLAC).
    

Detailed description: 
      Though it has been said, "once a cesarean, always a cesarean," the current medical stance has
      changed and now encourages vaginal birth after cesaren (VBAC) in a select population of
      patients. VBAC has several advantages over a repeat cesarean including decreased recovery
      period, decreased risk of infection, avoidance of major abdominal surgery, and lessened blood
      loss. Predictors for success of VBAC include previous spontaneous vaginal birth, singleton
      pregnancy, and previous low transverse scar for C-section delivery. TOLAC is a reasonable
      option for select pregnant women and is associated with a 74% likelihood of VBAC. Risk
      factors for failure of VBAC include labor dystocia, advanced maternal age, maternal obesity,
      fetal macrosomia, gestational age (GA) >40 weeks, short inter pregnancy interval, and
      preeclampsia.

      While success of VBAC is associated with fewer complications, failure of VBAC may be
      associated with increased complications. A major concern for VBAC is the possibility for
      uterine rupture, which may result in hysterectomy and intrapartum fetal hypoxia/death.
      According to the American College of Obstetricians and Gynecologists (ACOG) guidelines,
      effective regional analgesia should not be expected to mask the signs and symptoms of uterine
      rupture, particularly because the most common sign of rupture is fetal heart tracing
      abnormalities. Adequate pain relief achieved with either CSE or epidurals may even encourage
      more women to opt for VBAC. The decision to proceed with TOLAC should occur only after
      appropriate discussion of the risks and benefits has occurred between the patient and her
      obstetrician and as long as no other contraindications exist. The final decision should be
      left up to the patient. There is no reliable way to predict risk of uterine rupture, but it
      may be associated with classical and low vertical uterine scars, induction of labor, and
      increased number of prior cesarean deliveries and risk may be decreased by previous vaginal
      birth. Other aspects of VBAC versus repeat cesarean pertaining to the fetus to consider
      include respiratory function, mother-infant contact, and initiation of breastfeeding, which
      may be delayed in cesarean deliveries.

      There is very little research concerning the effects of CSEs and epidurals on women
      undergoing TOLAC.There have been multiple studies comparing CSE and epidurals on nulliparous
      and multiparous women, but none have been done specifically on patients undergoing TOLAC.
      According to the American Society of Anesthesiologists (ASA) practice guidelines for
      obstetric anesthesia "nonrandomized comparative studies suggest that epidural analgesia may
      be used in a trial of labor for previous cesarean delivery patients without adversely
      affecting the incidence of vaginal delivery. Randomized comparison of epidural versus other
      anesthetic techniques were not found." They agree that neuraxial techniques improve the
      likelihood of vaginal delivery for patients attempting VBAC and suggest neuraxial catheter be
      placed in event of operative delivery. Because no study to date has compared CSEs and
      epidurals and their effects on the success of VBAC, this study aims to further investigate
      this arena.
    

Intervention name(s): Epidural anesthesia; Combined spinal and epidural anesthesia
Intervention type(s): Drug; Drug
Intervention description(s): ￼An epidural involves injecting pain-blocking medication into a space between the vertebrae and the spinal fluid; it usually takes about 15 minutes to work.
Epidurals will be placed in a sterile fashion using a 17g Tuohy needle to locate the epidural space via loss-of-resistance to saline at the lumbar vertebral level. 3 ml of 1.5% lidocaine with 5ug/ml of epinephrine will then be used for test dose to exclude intrathecal or intravenous placement of the catheter. Epidural solution composed of 5ml of 0.2% ropivacaine and another 5 ml of 0.2% ropivacaine will then be administered.; A spinal is an injection directly into the spinal fluid; it is given in addition to the epidural technique and takes effect in five minutes.
The epidural space will be located with a 17g Tuohy needle and dural puncture performed with 25g Pencan needle via needle-through-needle technique. Spinal injection of 2ml 0.2% ropivacaine will then be performed and spinal needle removed. An epidural catheter will then be placed and test dose performed with 3 ml of 1.5% lidocaine with 5ug/ml of epinephrine. Maintenance dose will be via an epidural pump using 0.2% ropivacaine at a rate of 12 ml/hr.
Intervention MeSH terms: Anesthetics
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Single (Participant)
Primary purpose: Treatment
Keywords: trial of labor after cesarean; vaginal birth after cesarean; epidural vs combined spinal epidural