Programmed Intermittent Epidural Bolus for Labor Analgesia During First Stage of Labor: Comparing 125 mL/h Versus 250 mL/h Bolus Delivery Flow
Condition: Labor Pain
MeSH terms: Labor Pain
Study type: Interventional

Summary: 
      At Mount Sinai Hospital, epidural analgesia for labor pain is delivered by programmed
      intermittent epidural bolus (PIEB), in combination with pushes of medication activated by the
      patient, a technique called patient controlled epidural analgesia (PCEA). Studies have shown
      that delivering analgesia in this manner can prolong the duration of analgesia, diminish
      motor block, lower the incidence of breakthrough pain, improve maternal satisfaction and
      decrease local anesthetic consumption comparing to a conventional continuous infusion. The
      use of this PIEB technique in routine practice has reduced the total consumption of local
      anesthetic and the percentage of patients requesting additional boluses (PCEA or manual
      rescues).

      However, at the same time, sensory blocks above those targeted for labor pain relief have
      been reported in our institution, suggesting that the spread of the freezing medication is
      wider than necessary. Based on the information already available in the literature, the
      investigators will conduct this study to determine the best regimen of PIEB achievable with a
      slower delivery speed.

      The hypothesis of this study is that PIEB boluses with 125 mL/h will decrease by 50% the
      incidence of women presenting sensory block to ice equal or higher than T6 as compared to a
      delivery rate of 250 mL/h.
    

Detailed description: 
      PIEB is a novel technique, which provides better analgesia and less motor block; however, the
      ideal regimen has not been established. To optimize the PIEB regimen, the investigators have
      conducted several clinical trials using bupivacaine with fentanyl. Although PIEB provides the
      excellent analgesia to laboring parturients, studies completed by the instigators have shown
      that the incidence of sensory block to ice ≥T6 was 66%. For labor analgesia during the first
      stage of labor, effective sensory block requires T10 to L1; therefore, a sensory block ≥T6
      seems unnecessarily high, and the investigators seek to confine epidural spread within a
      proper range.

      Our previous studies showed that the effective volume 90% using 0.0625% bupivacaine was 10.7
      mL, and incidence of epidural blockade ≥T6 was similar even using a 5-mL bolus with 0.125%
      bupivacaine. The investigators concluded that it is not possible to reduce volume of the
      PIEB, or use a higher concentration of local anesthetic without compromising the quality of
      analgesia. There is some evidence in the literature that supports the idea that higher
      injection pressures result in a wider spread of local anesthetic administered into the
      epidural space, therefore a slower epidural delivery flow rate may result in less spread.
    

Intervention name(s): CADD-Solis Ambulatory Infusion System
Intervention type(s): Device
Intervention description(s): The CADD-Solis pump will administer programmed intermittent boluses of 0.0625% Bupivacaine plus fentanyl 2mcg/ml.
Allocation: Randomized
Intervention model: Parallel Assignment
Masking: Quadruple (Participant, Care Provider, Investigator, Outcomes Assessor)
Primary purpose: Treatment
Keywords: Epidural; Labor analgesia; Programmed intermittent epidural bolus