Foley Bulb Traction for Cervical Ripening
Condition: Cervical Ripening; Induction of Labor
Study type: Interventional

Summary: 
      This study aims to determine what type of traction, weighted bag or inner thigh taping, on
      foley catheters for cervical ripening results in a greater cervical dilation and shorter
      length of labor.

      The primary outcomes are post-ripening dilation of 3 cm or more and time to delivery.

      The secondary outcomes are patient pain/comfort rating and method of delivery. The
      investigators hypothesize that the use a weighted bag will result in a 20% increase in
      post-ripening dilation of at least 3 cm and a shorter average length of labor.
    

Detailed description: 
      Over the last 20 years the number of induced labors doubled so that over one in five births
      in 2003 was induced. In response to the rising need for cervical ripening the American
      College Obstetricians and Gynecologists have stated that both mechanical and prostaglandin
      ripening is acceptable and safe.

      Prior to beginning an induction, the Bishop score (cervical dilation, effacement, station,
      consistency, and position) is assessed. With Bishop scores less than five, a cervical
      ripening agent is commonly used. The mechanical dilation with a foley catheter works by both
      a direct stretching of the lower uterine segment and cervix and a local inflammatory response
      that releases matrix metalloproteinases and prostaglandins. It is often chosen due to its
      lower cost, low incidence of systemic side effects, and low risk of hyperstimulation.

      Compared to misoprostol a foley with oxytocin was more effective at induction in primiparous
      patients, more effective at improving the dilation, safe to use after misoprostol, and not
      associated with an increased risk of uterine rupture in a vaginal birth after cesarean
      (VBAC). The foley was also shown to have a shorter induction time and less contractile
      abnormalities than prostaglandin E2 gel and no increased rate of uterine rupture in VBAC
      attempts. The use of extra-amniotic saline infusion with a foley catheter has been used to
      augment the mechanical stretching, however this did not decrease the induction time or
      improve the outcomes. Finally, a Cochrane Database review found that mechanical methods of
      cervical ripening were equally effective as prostaglandin agents.

      Although the safety, efficacy, and side effects of foley catheter ripening have been compared
      with multiple other methods for cervical ripening, very few studies have compared different
      protocols for foley placement. One study showed that the use of oxytocin while the foley
      catheter was in place did not significantly shorten the time to delivery. Levy et al showed
      that a larger, 80 ml, balloon resulted in a greater post-ripening dilation and a higher
      number of deliveries in 24hours. No study to date has examined how the traction placed on the
      foley catheter affects the outcome.

      Therefore, we propose doing a randomized controlled study in which the control is the current
      standard of care at MetroHealth Medical Center of placing a 500cc weight on the foley and
      placing it to gravity over the end of the bed. The comparison will be the method used at many
      institutions where the foley catheter is placed on gentle traction and taped to the inner
      thigh of the patient.

      The primary outcomes measured will be a post-ripening dilation of 3cm or more and time to
      delivery. The secondary outcomes are patient pain/comfort rating and method of delivery.
    

Intervention name(s): weighted bag; leg taping
Intervention type(s): Other; Other
Intervention description(s): For the weighted bag, a 500cc saline bag will be taped to an empty Foley bag which will be attached to the cervical Foley catheter. This bag will then be placed to gravity over the end of the bed. The bed will be raised so that the bag does not touch the floor. The foley and the bag will be re-assessed every 30min by the nursing staff.; For the leg taping, the cervical foley catheter will be pulled to gentle traction and attached to the patient's inner thigh using a reclosable foley catheter fastener. The foley catheter and the traction will be assessed every 30min by the nursing staff. The tension will be renewed and the Foley re-adjusted if necessary at each check.
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: None (Open Label)
Primary purpose: Treatment
Keywords: cervical foley catheter